Two-stage aromatics hydrogenation of bitumen-derived light gas oil

In this research, two-stage hydrotreating of bitumen-derived light gas oil (LGO) from Athabasca oil sands was studied. The objective was to catalytically upgrade the LGO by reducing the aromatics content and enhancing the cetane content via inter-stage removal of hydrogen sulfide. The impact of hydrogen sulfide inhibition on aromatics hydrogenation (HDA), hydrodenitrogenation (HDN) and hydrodesulfirization (HDS) activities was investigated. Experiments for this study were carried out in a trickle-bed reactor loaded with commercial NiMo/Al2O3 and lab-prepared NiW/Al2O3 in the stage I and stage II reactors, respectively. Temperature was varied from 350 to 390 oC at the optimum LHSV and pressure conditions of 0.6 h-1 and 11.0 MPa, respectively. The results from two-stage process showed significant improvement in HDA, cetane rating and HDS activities compared to the single-stage process after the inter-stage removal of hydrogen sulfide. Hence, the presence of hydrogen sulfide in the reaction retarded both the HDA and HDS processes in the single-stage operation. Negligible hydrogen sulfide inhibition was however, observed in the HDN process. Prior to the two-stage hydrotreating study, single-stage hydrotreating reactions were carried out over commercial NiMo/Al2O3 catalyst to determine the optimum operating conditions for maximizing hydrogenation of aromatics. A statistical approach via the Analysis of Variance (ANOVA) technique was used to develop regression models for predicting the conversion of aromatics, sulfur and nitrogen in the LGO feed. Experiments were performed at the following operating conditions: temperature (340-390 oC); pressure (6.9-12.4 MPa) and liquid hourly space velocity, LHSV (0.5-2.0 h-1). Hydrogen-to-oil ratio was maintained constant at 550 ml/ml. The results showed that the two-level interaction between temperature and pressure was the only significant interaction parameter affecting HDA while interaction between temperature and LHSV was the most important parameter affecting both HDS and HDN activities. A maximum 63 % HDA was obtained at 379 oC, 11.0 MPa and 0.6 h-1. Experiments with NiW/Al2O3 were also performed in a single-stage reactor with LGO blend feedstock by varying temperature from 340-390 oC at the optimum pressure and space velocity of 11.0 MPa and 0.6 h-1, respectively. The following order of ease of hydrogenation was observed: poly- > di- >> monoaromatics. The order of ease of hydrogenation in other LGO feedstocks (atmospheric light gas oil, ALGO; hydrocrack light gas oil, HLGO; and vacuum light gas oil, VLGO) was studied and found to follow the order: VLGO > ALHO > HLGO. Studies on mild hydrocracking (MHC) in the gas oil feedstocks showed a net increase in gasoline with a corresponding decrease in diesel with increasing temperature. Both the single and two-stage HDA and HDS kinetics were modeled using Langmuir-Hinshelwood rate equations. These models predicted the experimental data with reasonable accuracy. The degree of conversion of the gas oil fractions in ALGO, HLGO and VLGO via mild hydrocracking was best described by a pseudo-first order kinetic model based on a parallel conversion scheme

Influence of Parasitic Worm Infections on Allergy Diagnosis in Sub-Saharan Africa.

Epidemiological studies from Sub-Saharan Africa indicate that allergies are on the rise in this region especially in urban compared to rural areas. This increase has been linked to improved hygiene, lifestyle changes, and lower exposure to pathogens in childhood. Reduced exposure to parasitic worm (helminth) infections and allergy outcomes has been the focus of a number of population studies over the years. Paradoxically, there are parallels in the immune responses to helminths and to allergies. Both conditions are associated with elevated levels of immunoglobulin E, high numbers of T helper 2 cells, eosinophils, and mast cells. These immune parallels have meant that the diagnosis of allergies in parts of the world where helminths are endemic can be hampered. The aim of this review is to examine observations from population studies conducted in Sub-Saharan Africa that demonstrate how helminth infections influence the parameters used to diagnose allergy outcomes in this region. We explore specifically how helminth infections hinder the in vitro diagnosis of allergic sensitization, influence the clinical manifestations of allergy, and also the effect of anthelmintic treatment on allergy outcomes. Advancing our understanding of how helminths influence allergy diagnosis is imperative for the development of improved tools to assess, diagnose, and treat allergic disorders in both helminth-endemic and non-endemic countries worldwide

Development of Convenient Cocoyam Pottage (Mpotompoto)

This study explored the feasibility of developing a ready-to-prepare cocoyam pottage, 'mpotompoto' to meet consumers' need for convenience in traditional dishes. Cocoyam chunks (1.2cm x 1.2cm x 1.2cm) were pre-gelatinized to obtain the instant base ingredient, and an accompanying spice-mix recipe was developed. Standard methods were used to determine the moisture content and selected functional properties of the ready-to-prepare base product. A consumer panel of fifty assessors who were familiar with sensory testing evaluated the product's organoleptic properties. A dish following a traditional recipe was used as control. The moisture content of the instant base was low (10%), signifying the potential for good storability. The water absorption capacity, oil absorption capacity, swelling power and solubility were 247.39 ± 7.12%, 87.98 ± 3.76%, 6.44 ± 0.58% and 3.78 ± 0.29%, respectively, indicating desirable functional characteristics for reconstitution. The consumer panel generally appreciated all evaluated products with mean likeness scores between 5 and 6 for all tested attributes on a 7-point hedonic scale. The convenient cocoyam pottage (mpotompoto) mimicked the traditionally prepared 'mpotompoto'. The study provides baseline information that can be commerciall

Development of Yoghurt Incorporated with Beetroot Puree and Its Effect on the Physicochemical Properties and Consumer Acceptance

Background Yoghurt is one of the most popularly consumed fermented products which provides several nutritional benefits. Yoghurt products often include flavour and colour additives however, growing awareness of the risks associated with synthetic food additives has necessitated the need to explore more natural colour and flavour as food additives. Methods This study evaluated the effect of beetroot puree as flavouring and colourant in yoghurt production and quality. To develop the yoghurt product, incubation time and proportion of beetroot puree were optimized based on the resulting pH, titratable acidity, colour, and viscosity using response surface methods. Results Optimum yoghurt formulations were obtained in products containing 2 %, 2.03 % and 8 % beetroot puree following an incubation of 2.5h. Increasing beetroot puree did not affect the pH and titratable acidity of the yoghurt samples but slightly influenced the viscosity of the yoghurt. The colour of yoghurt was mainly affected by the puree concentration. A consumer acceptance test was conducted on the optimized products compared to a control sample without beetroot. Yoghurt incorporated with 8 % beetroot puree was the least preferred with a mean score of 6.08, whereas yoghurt incorporated with 2.03 % beetroot puree was the most preferred (7.42), with a higher acceptance than the control (7.28). Conclusion /Implications for industry: Findings from the study provide evidence for exploration of beetroot yoghurt as a natural product alternative to the use of synthetic flavour and colour additives in yoghurt

Utilizing cocoyam (Xanthosoma sagittifolium) for food and nutrition security: A review

Publisher's version (útgefin grein)The critical role of indigenous crops in the socioeconomic growth of developing nations has necessitated calls for accelerated exploitation of staples. Cocoyam, Xanthosoma sagittifolium, is food for over 400 million people worldwide and is the most consumed aroid in West Africa. However, it remains an underexploited food resource. This study reviews existing literature and also makes use of primary data from interviews with indigenous cocoyam farmers, processors, consumers, and cocoyam scientists in the research Institutes of Ghana, to provide insight into existing nomenclature of the species, indigenous knowledge on food uses, nutritional value, and potential novel food applications of cocoyam. Adaptable technologies in conformity to new trends in food science that could be employed for in‐depth molecular studies and further exploitation of the crop are also discussed. It is envisaged that the provided information would contribute to global efforts aimed at exploiting the full potential of indigenous crops for sustainable food and nutrition security.DANIDA (12-PO8-GH): Strengthening Roots and Tuber Value Chains in GhanaPeer Reviewe

Mental health and quality of life burden in Buruli ulcer disease patients in Ghana

Background Buruli ulcer disease (BUD) is a necrotic skin neglected tropical disease (NTD) that has both a mental and physical health impact on affected individuals. Although there is increasing evidence suggesting a strong association between neglected tropical diseases (NTDs) and mental illness, there is a relative lack of information on BUD’s impact on the mental health and quality of life (QoL) of affected individuals in Ghana. This study is to assess the impact of BUD on mental health and quality of life of patients with active and past BUD infection, and their caregivers. Methods We conducted a case control study in 3 BUD endemic districts in Ghana between August and November 2019. Face-to-face structured questionnaire-based interviews were conducted on BUD patients with active and past infection, as well as caregivers of BUD patients using WHO Quality of Life scale, WHO Disability Assessment Schedule, Self-Reporting Questionnaire, Buruli Ulcer Functional Limitation Score and Hospital Anxiety and Depression Scale data tools. Descriptive statistics were used to summarize the characteristics of the study participants. Participant groups were compared using student t test and chi-square (χ2) or Fisher’s exact tests. Mean quality of life scores are reported with their respective 95% confidence intervals. Data was analysed using STATA statistical software. Results Our results show that BUD patients with active and past infection, along with their caregivers, face significant levels of distress and mental health sequelae compared to controls. Depression (P = 0.003) was more common in participants with active (27%) and past BU infection (17%), compared to controls (0%). Anxiety was found in 42% (11/26) and 20% (6/29) of participants with active and past BUD infection compared to 14% (5/36) of controls. Quality of life was also significantly diminished in active BUD infection, compared to controls. In the physical health domain, mean QoL scores were 54 ± 11.1 and 56 ± 11.0 (95% CI: 49.5‒58.5 and 52.2‒59.7) respectively for participants with active infection and controls. Similarly in the psychological domain, scores were lower for active infection than controls [57.1 ± 15.2 (95% CI: 50.9‒63.2) vs 64.7 ± 11.6 (95% CI: 60.8‒68.6)]. Participants with past infection had high QoL scores in both physical [61.3 ± 13.5 (95% CI: 56.1‒66.5)] and psychological health domains [68.4 ± 14.6 (95% CI: 62.7‒74.0)]. Conclusions BUD is associated with significant mental health distress and reduced quality of life in affected persons and their caregivers in Ghana. There is a need for integration of psychosocial interventions in the management of the disease

Caregiver burden in Buruli ulcer disease: Evidence from Ghana

Background Buruli ulcer disease (BUD) results in disabilities and deformities in the absence of early medical intervention. The extensive role of caregiving in BUD is widely acknowledged, however, associated caregiver burden is poorly understood. In this paper we assessed the burden which caregivers experience when supporting patients with BUD in Ghana. Method/ principal findings This qualitative study was conducted in 3 districts in Ghana between August and October 2019. 13 semi-structured interviews were conducted on caregivers of BUD patients in the local language of Twi. Data was translated into English, coded into broad themes, and direct content analysis approach was used to analyse results. The results show the caregivers face financial, psychological and health issues as a consequence of their caregiving role. Conclusion/ significance This study found significant caregiver burden on family members. It also highlighted the psychological burden caregivers experience and the limited knowledge of the disease within endemic communities. Further research is needed to quantify the caregiver burden of BUD at different economic levels in order to better understand the impact of possible caregiver interventions on patient outcomes. Author summary Buruli ulcer disease (BUD) is a stigmatizing skin condition caused by the bacteria, Mycobacterium ulcerans. The disease results in permanent functional limitations in the absence of early medical intervention. The disabling BUD conditions, financial constraints and frequent hospital visits support the role of caregiving for affected individuals. Caregiver burden is poorly understood although the role and need for caregiving is widely recognised in BUD. This study identified a previously unrecognized burden on the caregivers of BUD patients in 3 endemic districts in Ghana. Specifically, we identified significant financial and psychological pressure on affected families in meeting healthcare related costs and physical care while also providing for their own and other family members’ needs. We also highlight the emotional burden experienced by caregivers, their reduced work productivity, the barriers caregivers face in accessing healthcare with BUD patients and the limited support available for caregivers. Our study highlights the serious social consequences of BUD in Ghana. Further quantitative research within different economic regions affected by BUD is warranted to better understand the caregiver burden of BUD

High body mass index is not associated with atopy in schoolchildren living in rural and urban areas of Ghana

<p>Abstract</p> <p>Background</p> <p>Factors which determine the development of atopy and the observed rural-urban gradient in its prevalence are not fully understood. High body mass index (BMI) has been associated with asthma and potentially atopy in industrialized countries. In developing countries, the transition from rural to urban areas has been associated with lifestyle changes and an increased prevalence of high BMI; however, the effect of high BMI on atopy remains unknown in this population. We therefore investigated the association between high BMI and atopy among schoolchildren living in rural and urban areas of Ghana.</p> <p>Methods</p> <p>Data on skin prick testing, anthropometric, parasitological, demographic and lifestyle information for 1,482 schoolchildren aged 6-15 years was collected. Atopy was defined as sensitization to at least one tested allergen whilst the Centres for Disease Control and Prevention (CDC, Atlanta) growth reference charts were used in defining high BMI as BMI ≥ the 85^thpercentile. Logistic regression was performed to investigate the association between high BMI and atopy whilst adjusting for potential confounding factors.</p> <p>Results</p> <p>The following prevalences were observed for high BMI [Rural: 16%, Urban: 10.8%, p < 0.001] and atopy [Rural: 25.1%, Urban: 17.8%, p < 0.001]. High BMI was not associated with atopy; but an inverse association was observed between underweight and atopy [OR: 0.57, 95% CI: 0.33-0.99]. Significant associations were also observed with male sex [Rural: OR: 1.49, 95% CI: 1.06-2.08; Urban: OR: 1.90, 95% CI: 1.30-2.79], and in the urban site with older age [OR: 1.76, 95% CI: 1.00-3.07], family history of asthma [OR: 1.58, 95% CI: 1.01-2.47] and occupational status of parent [OR: 0.33, 95% CI: 0.12-0.93]; whilst co-infection with intestinal parasites [OR: 2.47, 95% CI: 1.01-6.04] was associated with atopy in the rural site. After multivariate adjustment, male sex, older age and family history of asthma remained significant.</p> <p>Conclusions</p> <p>In Ghanaian schoolchildren, high BMI was not associated with atopy. Further studies are warranted to clarify the relationship between body weight and atopy in children subjected to rapid life-style changes associated with urbanization of their environments.</p

Prenatal household air pollutant exposure is associated with reduced size and gestational age at birth among a cohort of Ghanaian infants.

BACKGROUND: Low birth weight and prematurity are important risk factors for death and disability, and may be affected by prenatal exposure to household air pollution (HAP). METHODS: We investigate associations between maternal exposure to carbon monoxide (CO) during pregnancy and birth outcomes (birth weight, birth length, head circumference, gestational age, low birth weight, small for gestational age, and preterm birth) among 1288 live-born infants in the Ghana Randomized Air Pollution and Health Study (GRAPHS). We evaluate whether evidence of malaria during pregnancy, as determined by placental histopathology, modifies these associations. RESULTS: We observed effects of CO on birth weight, birth length, and gestational age that were modified by placental malarial status. Among infants from pregnancies without evidence of placental malaria, each 1 ppm increase in CO was associated with reduced birth weight (-53.4 g [95% CI: -84.8, -21.9 g]), birth length (-0.3 cm [-0.6, -0.1 cm]), gestational age (-1.0 days [-1.8, -0.2 days]), and weight-for-age Z score (-0.08 standard deviations [-0.16, -0.01 standard deviations]). These associations were not observed in pregnancies with evidence of placental malaria. Each 1 ppm increase in maternal exposure to CO was associated with elevated odds of low birth weight (LBW, OR 1.14 [0.97, 1.33]) and small for gestational age (SGA, OR 1.14 [0.98, 1.32]) among all infants. CONCLUSIONS: Even modest reductions in exposure to HAP among pregnant women could yield substantial public health benefits, underscoring a need for interventions to effectively reduce exposure. Adverse associations with HAP were discernible only among those without evidence of placental malaria, a key driver of impaired fetal growth in this malaria-endemic area

Corrigendum to "Prenatal household air pollutant exposure is associated with reduced size and gestational age at birth among a cohort of Ghanaian infants" [Environ. Int. 155 (2021) 106659].

[This corrects the article PMC8628363.]