38 research outputs found

    Imputation, modelling and optimal sampling design for digital camera data in recreational fisheries monitoring

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    Digital camera monitoring has evolved as an active application-oriented scheme to help address questions in areas such as fisheries, ecology, computer vision, artificial intelligence, and criminology. In recreational fisheries research, digital camera monitoring has become a viable option for probability-based survey methods, and is also used for corroborative and validation purposes. In comparison to onsite surveys (e.g. boat ramp surveys), digital cameras provide a cost-effective method of monitoring boating activity and fishing effort, including night-time fishing activities. However, there are challenges in the use of digital camera monitoring that need to be resolved. Notably, missing data problems and the cost of data interpretation are among the most pertinent. This study provides relevant statistical support to address these challenges of digital camera monitoring of boating effort, to improve its utility to enhance recreational fisheries management in Western Australia and elsewhere, with capacity to extend to other areas of application. Digital cameras can provide continuous recordings of boating and other recreational fishing activities; however, interruptions of camera operations can lead to significant gaps within the data. To fill these gaps, some climatic and other temporal classification variables were considered as predictors of boating effort (defined as number of powerboat launches and retrievals). A generalized linear mixed effect model built on fully-conditional specification multiple imputation framework was considered to fill in the gaps in the camera dataset. Specifically, the zero-inflated Poisson model was found to satisfactorily impute plausible values for missing observations for varied durations of outages in the digital camera monitoring data of recreational boating effort. Additional modelling options were explored to guide both short- and long-term forecasting of boating activity and to support management decisions in monitoring recreational fisheries. Autoregressive conditional Poisson (ACP) and integer-valued autoregressive (INAR) models were identified as useful time series models for predicting short-term behaviour of such data. In Western Australia, digital camera monitoring data that coincide with 12-month state-wide boat-based surveys (now conducted on a triennial basis) have been read but the periods between the surveys have not been read. A Bayesian regression framework was applied to describe the temporal distribution of recreational boating effort using climatic and temporally classified variables to help construct data for such missing periods. This can potentially provide a useful cost-saving alternative of obtaining continuous time series data on boating effort. Finally, data from digital camera monitoring are often manually interpreted and the associated cost can be substantial, especially if multiple sites are involved. Empirical support for low-level monitoring schemes for digital camera has been provided. It was found that manual interpretation of camera footage for 40% of the days within a year can be deemed as an adequate level of sampling effort to obtain unbiased, precise and accurate estimates to meet broad management objectives. A well-balanced low-level monitoring scheme will ultimately reduce the cost of manual interpretation and produce unbiased estimates of recreational fishing indexes from digital camera surveys

    Environmentally friendly agent against fall armyworm (Spodoptera frugiperda): Antifeedant potency of mentha spicata aqueous extracts

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    The rising trends of insect resistance, coupled with escalating environmental pollution from synthetic pesticides, heighten the need for a more effective and, non-hazardous agents to control insect/pests. Different aqueous extracts of Mentha spicata were screened for their phytochemical constituents and their antifeedant activities against Spodoptera frugiperda. Screening of the different aqueous extracts of Mentha spicata obtained by cold maceration revealed the presence of phenolics and tannins. The concentration of phenols and tannins in the water, glycerine, and glycerine plus water (glycerine-water) extracts were significantly different (p \u3c 0.05). Mentha spicata water extract had a greater antifeedant activity against Spodoptera frugiperda as compared to glycerine and glycerine-water (60 : 40, v/v) extracts at a concentration of 5g/100 mL. The estimated % antifeedant activity recorded were 97 as against 8.21 and 49.81, respectively. Aqueous neem seed water extracts gave an estimated % antifeedant activity of 93.07 and it served as a control. Saponins were absent in all extracts and only water extracts had alkaloids present. The simple, non-hazardous, and cost-saving extraction method demonstrated could be applied in both commercial and subsistent farming to counteract the damnable effects of Spodoptera frugiperda infestation

    Trade-off assessments between reading cost and accuracy measures for digital camera monitoring of recreational boating effort

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    Digital camera monitoring is increasingly being used to monitor recreational fisheries. The manual interpretation of video imagery can be costly and time consuming. In an a posteriori analysis, we investigated trade-offs between the reading cost and accuracy measures of estimates of boat retrievals obtained at various sampling proportions for low, moderate and high traffic boat ramps in Western Australia. Simple random sampling, systematic sampling and stratified sampling designs with proportional and weighted allocation were evaluated to assess trade-offs in terms of bias, accuracy, precision, coverage rate and cost in estimating the annual total number of powerboat retrievals in 10,000 jackknife resampling draws. The relative standard error (RSE ± standard deviations) obtained by the sampling designs for sampling proportions from 0.4 onwards were below a 20 % threshold for three of the sampling designs across the three boat ramps. Coverage rates of over 90 % were observed for the confidence intervals for the estimated annual number of powerboat retrievals, with low relative standard errors (RSE \u3c 20 %). Interpreting 40 % of camera footage within a year provided the minimum level to obtain sufficient accuracy measures for all sampling designs considered. The stratified random sampling design with weighted allocation consistently resulted in the smallest variance for estimates of annual powerboat retrievals across the various sampled proportions. These findings have the potential to considerably reduce the cost of manual data interpretation, since operating cost increased linearly with increasing sampling proportion

    Mediation roles of pedagogical approaches and personality traits in entrepreneurial curriculum design and entrepreneurial intention nexus

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    Planned behaviour theory was used in a path analysis modelling to investigate the serial mediation role of teaching methods and personality traits (locus of control, need for achievement and entrepreneurial attitude) in the relationship between entrepreneurship curriculum and entrepreneurial intention among university students in Ghana. A proposed 40-item instrument was used to measure outcomes for six constructs (3 personality trait constructs, entrepreneurship curriculum, teaching methods and entrepreneurial intention) for 324 participants. Acceptable convergent, divergent and construct validity scores were observed for the instrument. Teaching methods fully mediated the first-order relationships between entrepreneurial curriculum and each personality traits. The three constructs of personality traits parallelly mediated the second-order relationship between teaching methods and entrepreneurial intention. Teaching methods and each personality trait serially mediated the relationship between entrepreneurial curriculum and entrepreneurial intention. This empirical evidence provides insight into the design of pragmatic interventions by major stakeholders including entrepreneurship educators to inspire students into start-up activitie

    Perceived nexus between non-invigilated summative assessment and mental health difficulties: A cross sectional studies

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    The COVID-19 pandemic rapidly led to changes in the mode of teaching, learning and assessments in most tertiary institutions worldwide. Notably, non-invigilated summative assessments became predominant. These changes heightened anxiety and depression, especially among individuals with less resilient coping mechanism. We explored the perceptions and experiences of mental health difficulties of students in tertiary education regarding non-invigilated alternative assessments in comparison to invigilated assessments. A pragmatic, mixed method cross sectional design was conducted online via Qualtrics. Thematic analysis of text was carried out using NVivo 12. In the quantitative analysis, univariable and multivariable ordinal logistic models were used to examine the potential factors for preference among students in higher education. A total of 380 Nursing and Social Science students responded to the survey. Approximately 77% of students perceived non-invigilated assessments to be less stressful compared to invigilated exams. Age, course of study, stage of studies, and number of units enrolled per semester were identified as significant drivers for students’ perceived preference for non-invigilated assessments. There was an inverse relationship between the perception of stress associated with invigilated exams and the age of students. For instance, students aged between 18-24 were 5 times more likely to prefer non-invigilated exams compared to those aged 55 or more. Comparatively, students in early stages of studies had higher preference for non-invigilated assessments. However, there was a preference reversal for students enrolled in 2 or less units per semester. Social sciences students were two times more likely to prefer non-invigilated examinations to invigilated examinations compared to nursing students. The findings reinforce the use of alternative assessments in higher education as a mitigating agency to lessen the mental health burden of tertiary students in post COVID-19 era

    Confirmatory factor analysis and reliability of the Diabetes Treatment Satisfaction Questionnaire (DTSQ) for Arabic speaking patients with type II diabetes

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    Background: Treatment satisfaction is an important indicator for treatment compliance and glycemic control. Although psychometric properties of the Diabetes Treatment Satisfaction Questionnaire have been confirmed in several languages, it remains unclear the extent to which the factorial structure of this tool is valid for Arabic speaking populations. Purpose: This study set out to confirm the construct validity of the Arabic version of the Diabetes Treatment Satisfaction Questionnaire (DTSQ) by investigating the fit of published factor structures and the reliability of responses in patients diagnosed with type 2 diabetes. Methods: Data were from a large cross-sectional study of 1002 patients with diabetes in Jordan. Confirmatory factor analysis was used to compare three different models of the 8-item questionnaire (one factor, two factors, three factors) across patients treated with insulin and patients treated with oral hypoglycaemic medications. Results: Statistics covered the factorial validity and omega reliability coefficient (Ωw) of the DTSQ. We were able to replicate the three different models of the 8-item Diabetes Treatment Satisfaction Questionnaire reported in previous studies, yet a two-factor model provided the best fit to the data in our sample with omega reliability coefficient (Ωw) of the subscales above 0.70. Conclusion: The finding suggests a cross-cultural invariance of the factor structure of the Arabic version of the Diabetes Treatment Satisfaction Questionnaire, as we were able to replicate the same factor structure using the Arabic translated version of the tool and using non-English speaking participants. Within known limitations and gaps in the literature, healthcare professionals working with Arabic speaking patients may find this tool useful for identification of high-risk patients and those in need for interventions to promote glycemic control

    Imputation of missing data from time-lapse cameras used in recreational fishing surveys

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    While remote camera surveys have the potential to improve the accuracy of recreational fishing estimates, missing data are common and require robust analytical techniques to impute. Time-lapse cameras are being used in Western Australia to monitor recreational boating activities, but outages have occurred. Generalized linear mixed effect models formulated in a fully conditional specification multiple imputation framework were used to reconstruct missing data, with climatic and some temporal classifications as covariates. Using a complete 12-month camera record of hourly counts of recreational powerboat retrievals, data were simulated based on ten observed camera outage patterns, with a missing proportion of between 0.06 and 0.61. Nine models were evaluated, including Poisson and negative binomial models, and their associated zero-inflated variants. The imputed values were cross-validated against actual observations using percent bias, mean absolute error, root mean square error, and skill score as performance measures. In 90% of the cases, 95% confidence intervals for the total imputed estimates from at least one of the models contained the total actual counts. With no systematic trends in performance among the models, zero-inflated Poisson and its bootstrapping variant models consistently ranked among the top 3 models and possessed the narrowest confidence intervals. The robustness and generality of the imputation framework were demonstrated using other camera datasets with distinct characteristics. The results provide reliable estimates of the number of boat retrievals for subsequent estimates of fishing effort and provide time series data on boat-based activity

    A retrospective cohort study of factors associated with severity of falls in hospital patients

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    Severity of falls in hospital patients are threat to patient safety which can result in a financial burden on the patient’s family and health care services. Both patient specific and environmental and organisational factors are associated with severity of falls in hospital. It is important to continuously analyse the factors associated with severity of fall which can inform the implementation of any fall preventive strategies. This study aims to identify factors associated with the severity of falls in hospitalised adult patients in Western Australia. This study involved a retrospective cohort analysis of inpatient falls records extracted from the hospital’s Clinical Incident Database from May 2014 to April 2019. Severity of falls were classified as three Severity Assessment Code (SAC): SAC 1 was “high” causing serious harm or death; SAC 2 was “medium” causing moderate or minor harm; and SAC 3 was “low” indicating no harm. Univariable and multivariable generalised ordinal logistic regression models were used to quantify the magnitude of effects of the potential risk factors on severity of falls at 5 % level of significance and reported the crude odds and adjusted odds ratio of falling at a higher severity level. There were 3705 complete reported cases of falls with the average age of the patients was 68.5 ± 17.0 years, with 40.2 % identified as female. The risk of falling at a higher level of severity increased by patient age over 50 years. Females were 15.1 % more likely to fall at higher severity level compared to females. Fall incidents occurred during toileting and showering activities and incidents in a communal area were 14.5 % and 26 % more likely to occur at a higher severity respectively. Similarly, depression (167 %), influence of alcohol or illicit drugs (more than 300 %), use of medications (86 %) and fragile skin (75 %) significantly increased the odds of falling at higher level of severity. Identification of underlying risk factors associated with fall severity provides information which can guide nurses and clinicians to design and implement effective interventional strategies that mitigate the risk of serious fall injuries. The results suggest that fall prevention strategies should target patients with these risk factors to avoid severity of falls

    Conceptualised psycho-medical footprint for health status outcomes and the potential impacts for early detection and prevention of chronic diseases in the context of 3P medicine

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    Background: The Suboptimal Health Status Questionnaire-25 (SHSQ-25) is a distinctive medical psychometric diagnostic tool designed for the early detection of chronic diseases. However, the synaptic connections between the 25 symptomatic items and their relevance in supporting the monitoring of suboptimal health outcomes, which are precursors for chronic diseases, have not been thoroughly evaluated within the framework of predictive, preventive, and personalised medicine (PPPM/3PM). This baseline study explores the internal structure of the SHSQ-25 and demonstrates its discriminatory power to predict optimal and suboptimal health status (SHS) and develop photogenic representations of their distinct relationship patterns. Methods: The cross-sectional study involved healthy Ghanaian participants (n = 217; aged 30–80 years; ~ 61% female), who responded to the SHSQ-25. The median SHS score was used to categorise the population into optimal and SHS. Graphical LASSO model and multi-dimensional scaling configuration methods were employed to describe the network structures for the two populations. Results: We observed differences in the structural, node placement and node distance of the synaptic networks for the optimal and suboptimal populations. A statistically significant variance in connectivity levels was noted between the optimal (58 non-zero edges) and suboptimal (43 non-zero edges) networks (p = 0.024). Fatigue emerged as a prominently central subclinical condition within the suboptimal population, whilst the cardiovascular system domain had the greatest relevance for the optimal population. The contrast in connectivity levels and the divergent prominence of specific subclinical conditions across domain networks shed light on potential health distinctions. Conclusions: We have demonstrated the feasibility of creating dynamic visualizers of the evolutionary trends in the relationships between the domains of SHSQ-25 relative to health status outcomes. This will provide in-depth comprehension of the conceptual model to inform personalised strategies to circumvent SHS. Additionally, the findings have implications for both health care and disease prevention because at-risk individuals can be predicted and prioritised for monitoring, and targeted intervention can begin before their symptoms reach an irreversible stage. We observed differences in the structural, node placement and node distance of the synaptic networks for the optimal and suboptimal populations. A statistically significant variance in connectivity levels was noted between the optimal (58 non-zero edges) and suboptimal (43 non-zero edges) networks (p = 0.024). Fatigue emerged as a prominently central subclinical condition within the suboptimal population, whilst the cardiovascular system domain had the greatest relevance for the optimal population. The contrast in connectivity levels and the divergent prominence of specific subclinical conditions across domain networks shed light on potential health distinctions

    Using intervention analysis to evaluate the trends in release rates of recreational fisheries following extensive management changes

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    Changes to management of a fisheries resource are often required to ensure ongoing sustainability. However, such changes can sometimes lead to unintended effects such as increased release rates and associated post-release mortality. These effects may be highly variable between species and areas. Recreational fishing management changes were introduced on the west coast of Australia in 2009/10 to recover stocks of demersal scalefish. Key changes included reducing mixed species bag limits across management zones and increasing the minimum size limit for one species in some management zones. The restrictive catch limits resulted in increased release rates of key demersal species. However, whether such increases are significant and sustained over time, and thus of management concern, have not been evaluated. We carried out intervention time series analysis to evaluate the impact of management changes on release rates of four key demersal species for the recreational sector in metropolitan and regional management zones covering ∼8° latitude using an 18-year time series of charter recreational fishery data from July 2002 to January 2020. We observed varying responses in release rates by species and zones, the most common of which were a step increase, a ramp and a temporary increase that decayed. These responses may be related to targeted management changes which influenced fisher behaviour, perceived recreational value of some species and recruitment variation. Our study demonstrates that intervention analysis, which has seen limited use in this context, can assist in evaluating the impact of management changes on different species for recreational fisheries
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