Bayesian Models for Zero Truncated Count Data. Asian Journal of Probability and Statistics.

It is important to fit count data with suitable model(s), models such as Poisson Regression, Quassi Poisson, Negative Binomial, to mention but a few have been adopted by researchers to fit zero truncated count data in the past. In recent times, dedicated models for fitting zero truncated count data have been developed, and they are considered sufficient. This study proposed Bayesian multi-level Poisson and Bayesian multi-level Geometric model, Bayesian Monte Carlo Markov Chain Generalized linear Mixed Models (MCMCglmms) of zero truncated Poisson and MCMCglmms Poisson regression model to fit health count data that is truncated at zero. Suitable model selection criteria were used to determine preferred models for fitting zero truncated data. Results obtained showed that Bayesian multi-level Poisson outperformed Bayesian multi-level Poisson Geometric model; also MCMCglmms of zero truncated Poisson outperformed MCMCglmms Poisson

Approximation techniques for maximizing likelihood functions of generalized linear mixed models for binary response data

Evaluating Maximum likelihood estimates in Generalized Linear Mixed Models (GLMMs) has been a serious challenge due to some integral complexities encountered in maximizing its likelihood functions. It is computationally difficult to establish analytical solutions for the integrals. In view of this, approximation techniques would be needed. In this paper, various approximation techniques were exam-ined including Laplace approximation (LA), Penalized Quasi likelihood (PQL) and Adaptive Gauss-Hermite Quadrature (AGQ) tech-niques. The performances of these methods were evaluated through both simulated and real-life data in medicine. The simulation results showed that the Adaptive Gauss-Hermit Quadrature approach produced better estimates when compared with PQL and LA estimation techniques based on some model selection criteria

Performance of aquatic plant species for phytoremediation of arsenic-contaminated water

This study investigates the effectiveness of aquatic macrophyte and microphyte for phytoremediation of water bodies contaminated with high arsenic concentration. Water hyacinth (Eichhornia crassipes) and two algae (Chlorodesmis sp. and Cladophora sp.) found near arsenic-enriched water bodies were used to determine their tolerance toward arsenic and their effectiveness to uptake arsenic thereby reducing organic pollution in arsenic-enriched wastewater of different concentrations. Parameters like pH, chemical oxygen demand (COD), and arsenic concentration were monitored. The pH of wastewater during the course of phytoremediation remained constant in the range of 7.3–8.4, whereas COD reduced by 50–65 % in a period of 15 days. Cladophora sp. was found to survive up to an arsenic concentration of 6 mg/L, whereas water hyacinth and Chlorodesmis sp. could survive up to arsenic concentrations of 2 and 4 mg/L, respectively. It was also found that during a retention period of 10 days under ambient temperature conditions, Cladophora sp. could bring down arsenic concentration from 6 to <0.1 mg/L, Chlorodesmis sp. was able to reduce arsenic by 40−50 %; whereas, water hyacinth could reduce arsenic by only 20 %. Cladophora sp. is thus suitable for co-treatment of sewage and arsenic-enriched brine in an algal pond having a retention time of 10 days. The identified plant species provides a simple and cost-effective method for application in rural areas affected with arsenic problem. The treated water can be used for irrigation

Differing impact of the COVID-19 pandemic on youth mental health: combined population and clinical study

Background: Identifying youths most at risk to COVID-19-related mental illness is essential for the development of effective targeted interventions. Aims: To compare trajectories of mental health throughout the pandemic in youth with and without prior mental illness and identify those most at risk of COVID-19-related mental illness. Method: Data were collected from individuals aged 18-26 years (N = 669) from two existing cohorts: IMAGEN, a population-based cohort; and ESTRA/STRATIFY, clinical cohorts of individuals with preexisting diagnoses of mental disorders. Repeated COVID-19 surveys and standardised mental health assessments were used to compare trajectories of mental health symptoms from before the pandemic through to the second lockdown. Results: Mental health trajectories differed significantly between cohorts. In the population cohort, depression and eating disorder symptoms increased by 33.9% (95% CI 31.78-36.57) and 15.6% (95% CI 15.39-15.68) during the pandemic, respectively. By contrast, these remained high over time in the clinical cohort. Conversely, trajectories of alcohol misuse were similar in both cohorts, decreasing continuously (a 15.2% decrease) during the pandemic. Pre-pandemic symptom severity predicted the observed mental health trajectories in the population cohort. Surprisingly, being relatively healthy predicted increases in depression and eating disorder symptoms and in body mass index. By contrast, those initially at higher risk for depression or eating disorders reported a lasting decrease. Conclusions: Healthier young people may be at greater risk of developing depressive or eating disorder symptoms during the COVID-19 pandemic. Targeted mental health interventions considering prior diagnostic risk may be warranted to help young people cope with the challenges of psychosocial stress and reduce the associated healthcare burden

Breastfeeding and breastmilk substitute use and feeding motivations among mothers in Bandung City, Indonesia

Abstract: Suboptimal breastfeeding is common in Indonesia, with only half of infants 0–5 months of age exclusively breastfed and feeding of breastmilk substitutes (BMS) highly prevalent among infants and toddlers. Various factors influence these feeding practices, including social norms, limited health system support and BMS manufacturer marketing practices. This cross‐sectional survey aimed to identify the prevalence of breastfeeding and BMS feeding among children aged 0–35 months, explore socio‐demographic characteristics and motivating factors associated with these feeding behaviours and identify the prevalence of mothers' exposure to BMS promotions. Indonesian mothers of children <3 years of age (n = 595) were interviewed in Bandung City health facilities using structured questionnaires. Although all children were ever breastfed, half of children across all age groups received BMS in the previous day. Maternal employment outside the home and insufficient breastmilk production were associated with BMS use. The most important motivational factors for feeding BMS were perceived benefits for growth, intelligence and immunity. Despite Indonesian legislation restricting some BMS marketing, 93% of mothers reported observing a BMS promotion outside the health system, with television, social media and newspapers as the most common sources. Half of mothers (43%) reported observing a BMS promotion within the health system, and half (46%) reported receiving recommendations from health workers to use BMS. Such high prevalence of BMS marketing may be influencing caregivers' feeding choices; stronger national legislation and implementation of laws are needed to ensure mothers' ability to make feeding choices free from manufacturer influence

An assessment of the risk of Bt-cowpea to non-target organisms in West Africa

Cowpea (Vigna unguiculata Walp.) is the most economically important legume crop in arid regions of sub-Saharan Africa. Cowpea is grown primarily by subsistence farmers who consume the leaves, pods and grain on farm or sell grain in local markets. Processed cowpea foods such as akara (a deep-fat fried fritter) are popular in the rapidly expanding urban areas. Demand far exceeds production due, in part, to a variety of insect pests including, in particular, the lepidopteran legume pod borer (LPB) Maruca vitrata. Genetically engineered Bt-cowpea, based on cry1Ab (Event 709) and cry2Ab transgenes, is being developed for use in sub-Saharan Africa to address losses from the LBP. Before environmental release of transgenic cowpeas, the Bt Cry proteins they express need to be assessed for potential effects on non-target organisms, particularly arthropods. Presented here is an assessment of the potential effects of those Cry proteins expressed in cowpea for control of LPB. Based on the history of safe use of Bt proteins, as well as the fauna associated with cultivated and wild cowpea in sub-Saharan Africa results indicate negligible effects on non-target organisms

Use of Siam weed biomarker in assessing heavy metal contaminations in traffic and solid waste polluted areas

The ability of Chromolaena odorata to accumulate and serve as biomarker to lead and cadmium metals pollution load had been revealed by this study. Samples of soils and Siam weed were collected to assess impacts of solid waste disposal and traffic density on the environment. Composite sample were collected from a solid waste dumpsite, three traffic polluted areas with varying traffic density and a background site distant from traffic. Concentration of eight elements: cadmium, cobalt, chromium, copper, iron, nickel, lead and zinc were determined in soil and plant samples and correlated together. Accumulative factors like pollution load index, transfer factor, contamination factor, enrichment factor were calculated for the metals in both plants and soils and used as basis for interpreting the state of the environment and ability of C. odorata to accumulate metals. The accumulative factors of plants were generally greater than that of soil samples indicating increased accumulative capacity of the plant. The accumulations of lead and cadmium in C. odorata were remarkable with contamination factor 10.51 and 23.50, respectively and mean enrichment factors 3.52 and 6.93, respectively. Other metals had lower accumulative factors. The distribution of metals and calculated factors placed solid waste disposal site as the most polluted site while the trend observed in areas with traffic pollution depicts the ability of C. odorata to clean up metal pollution by accumulating them. It can therefore be suggested that solid waste disposal negatively affects the environment more than traffic pollution subject to the volume of traffic

Draft genome sequence of aeromonas caviae strain A1-2, a potential plant growth-promoting rhizospheric bacterium

The genomic analysis of the plant growth-promoting rhizospheric Aeromonas caviae strain A1-2, which was isolated from a maize plant in Northwest Province, South Africa, is presented in this paper. Aeromonas caviae strain A1-2 demonstrates its potential to promote plant growth and enhance the tolerance of maize plants to drought stress