Monitoring Impervious Surface Area Dynamics to Assess Urbanisation of a Catchment: Msimbazi River Valley Dar es Salaam, 1989 - 2015

This work examined the effects of land use and cover change on the impervious surface as a measure of urbanisation together with its driving factors such as population growth and economic development. The spatial and temporal variations of the impervious surface area were extracted from the Landsat images of the years 1989, 1995, 2005, and 2015. Data analyses involved the selection of the endmember through Minimum Noise Fraction (MNF) and Linear Spectral Mixed Analysis (LSMA) on the images. Four dominant land cover types were mapped as results, which are forest, non-forest vegetation, bare-land, and built-up area. The non-forest vegetation and bare land were dominant cover classes in the catchment in 1989, occupying over 80% of the land use and cover. The built-up environment increased from 11% in 1989 to 53% in 2015, encroaching other covers. This correlates with the growth of population and gross domestic product as measures of economic development and driving forces for the growth. Keywords: Land use; Impervious Surface Area; Urbanisation; Msimbazi River; Minimum Noise Fractio

Urban Dietary Heavy Metal Intake from Protein Foods and Vegetables in Dar Es Salaam

Contamination of food and food products by heavy metals has made dietary intake as one of the major routes of these harmful elements to human beings. The human dietary intake of heavy metals cadmium, copper, lead and zinc from protein-foods (beans, meat, fish, milk) and green vegetables consumed daily from restaurants and street food-vendor kiosks in Dar es Salaam were determined using the Total Diet Study (TDS) method. The cooked food was bought from the restaurants and street food-vendors at several city locations (i.e. Buguruni, Manzese, Mwenge, Temeke and Ubungo) over several months and analyzed. Heavy metal concentrations were determined by Atomic Absorption Spectrophotometry (AAS) after wet digestion of the edible portions of pooled samples of the foodstuff. The results showed significant variation in heavy metal concentration among the foodstuff and at the different locations. The results were compared to the FAO/WHO levels for Acceptable Daily Intake (ADI) and Provisional Tolerable Weekly Intake (PTWI) to estimate risk of toxicity and to the US Recommended Dietary Allowance (RDA) and/or Estimated Safe and Adequate Daily Dietary Intake (ESADDI) for a deficiency in intake. The average weekly dietary intake of cadmium and lead from protein-foods and vegetables ranged from 0.20 - 0.42 µg/kg-bw/week (i.e. 2.82 - 6.00% of PTWI) and 4.77 - 9.83 µg/kg-bw/week (i.e. 68.1 – 140.4% of PTWI) respectively. These dietary intakes were below the ADI values of 0.5 µg/kg-bw/day and 3.6 µg/kg-bw/day of the WHO for cadmium and lead respectively. The daily dietary intake of zinc and copper at all the locations were also below the ADI for these elements, the average being 21.5% for copper and 19.8% for zinc. The results show clearly that the daily urban dietary intake of copper and zinc, from protein foods and vegetables along main streets at the above locations, was acceptable.Keywords: Heavy metal, dietary intake, protein foods, vegetables, Dar es SalaamTanz. J. Sci. Vol 36 2010, 85-9

Dry Method for Preparation of Inulin Biomass as a Feedstock For Ethanol Fermentation

Sisal leaves which constitute only 2% of the sisal plant have been used in the production of pulp and fiber; the remaining 98% which is mostly of the sisal bole is largely regarded as waste. The bole's high inulin fraction (24-36%) is of particular significance due to its chemical functionality and relative ease of fermentation. utilisationThe objective of this study was to identify properties and pertinent characteristics for developing industrially viable methods of extracting inulin from sisal bole in a readily utilisable form. Inulin was extracted using the dry method 'baking', whereby sisal boles were chopped into chips of defined sizes 1.5-6 cm, before drying at 70 - 150 \ub0C. The dried bole chips were milled to sieved powder of 90-2000 \u3bcm. Particle sizes and temperature for total sugars were determined using the dinitrosalicylic (DNS) colorimetric method. Prior to fermentation, the inulin was hydrolysed using sulphuric acid to give a total sugar yield of 5-16% wt/wt depending on drying temperature. In general, high temperatures, e.g. 150 \ub0C led to low sugar recovery (10.3% wt/wt), while low temperatures, e.g. 70 \ub0C gave high sugar recovery (16.3% wt/wt). The fine inulin powder (<250 \u3bcm) was richer sugar content (~16%), whereas coarse particles (>400 \u3bcm) gave low sugar levels (~9%). The hydrolysed inulin was fermented using Saccharomyces cerevisiae for 57 hours giving consistent ethanol yields depending on initial sugar levels.Les feuilles de Sisal constituant seulement 2% de toute la plante ont \ue9t\ue9 utilis\ue9 dans la production des pulpes et fibres, et 98 % du reste constituent le tronc \ue9tait consud\ue9r\ue9 comme d\ue9chet. Le tronc du Sisal poss\ue8de une fraction \ue9lev\ue9e de (24-36 %) d'une importance particuli\ue8re par ses fonctionnalit\ue9s chimiques et la facilit\ue9 relative de fermentation. Cet article parle de l'utilisation du polysaccarose du sisal (Agave Americana) \ue0 travers la m\ue9thode s\ue8che comme un potential du feedstock pour la production de l'\ue9thanol. Cette \ue9tude visait l'identification des proprieties et des caract\ue9ristiques pertinantes pour le d\ue9veloppement industrielle viable des m\ue9thodes d'extraction de l'inulin du tronc du sisal en une forme utilisable. L'extraction de l'inulin par la m\ue9thode s\ue8che baking \ue9tait consid\ue9r\ue9e, par laquelle les troncs de sisal \ue9taient coup\ue9s en morceaux de dimensions d\ue9finies (1.5-6 cm) et s\ue9ch\ue9s \ue0 70-150 \ub0C. Les morceaux s\ue9ch\ue9s \ue9taient moulus pour g\ue9n\ue9rer une poudre de 90-2000 \u3bcm \ue0 l'aide d'un tamis d'analyse. La d\ue9termination de diff\ue9rentes dimensions de particules et temp\ue9rature des sucres \ue9tait faite par la m\ue9thode colorim\ue9trique dinitrosalicylique (DSN). Avant la fermentation, l'inulin \ue9tait hydrolys\ue9 \ue0 l'aide de l'acide sulfurique pour donner un rendement total en sucre de 5 16 % wt/wt sur base de la temp\ue9rature de s\ue9chage. En g\ue9n\ue9ral, les temp\ue9ratures \ue9lev\ue9es telle que celle de 150 \ub0C avaient donn\ue9 un bas recouvrement de sucre (10.3% wt/wt) alors que de temp\ue9ratures basses dont 70 \ub0C avaient produit un recouvrement \ue9lev\ue9 (16.3% wt/wt). La poudre de l'inulin fine (<250 \u3bcm) a exhib\ue9 un taux \ue9lev\ue9 de sucre (~16%), alors que les particules grossi\ue8res (>400 \u3bcm) avait donn\ue9 un taux bas d'environ 9 %. L'inulin hygrolys\ue9 \ue9tait ferment\ue9 utilisant le Saccharomyces cerevisiae pendant 57 heures donnant de rendements consistants d'\ue9thanol d\ue9pendamment de niveaux initiaux du sucre

Sexual behavior, psychosocial and knowledge differences between consistent, inconsistent and non-users of condoms: a study of female bar and hotel workers in Moshi, Tanzania.

Understanding psychosocial, sexual behavior and knowledge differences between never, inconsistent and consistent condom users can improve interventions to increase condom use in resource-poor countries, but they have not been adequately studied. We examined these differences in a cohort of 961 female hotel and bar workers in Moshi, Tanzania. Forty-nine percent of women reported no condom use; 39% reported inconsistent use, and 12% reported consistent use. Women with multiple sexual partners in the past five years were less likely to be consistent rather than inconsistent users as were women who had ever exchanged sex for gifts or money. Inconsistent users had higher condom knowledge and higher perceived acceptability of condom use than did never users, but they did not differ from consistent users by these factors. There are important differences between women by level of condom use. These findings can help inform interventions to increase condom use

Insect pollination is important in a smallholder bean farming system

Background: Many crops are dependent on pollination by insects. Habitat management in agricultural landscapes can support pollinator services and even augment crop production. Common bean (Phaseolus vulgaris L.) is an important legume for the livelihoods of smallholder farmers in many low-income countries, particularly so in East Africa. While this crop is autogamous, it is frequently visited by pollinating insects that could improve yields. However, the value of pollination services to common beans (Kariasii) yield is not known. Methods: We carried out pollinator-exclusion experiments to determine the contribution of insect pollinators to bean yields. We also carried out a fluorescent-dye experiment to evaluate the role of field margins as refuge for flower-visitors. Results: Significantly higher yields, based on pods per plant and seeds per pod, were recorded from open-pollinated and hand-pollinated flowers compared to plants from which pollinators had been excluded indicating that flower visitors contribute significantly to bean yields. Similarly, open and hand-pollinated plants recorded the highest mean seed weight. Extrapolation of yield data to field scale indicated a potential increase per hectare from 681 kg in self-pollinated beans to 1478 kg in open-pollinated beans indicating that flower visitors contributed significantly to crop yield of beans. Our marking study indicated that flower-visiting insects including bees, flies and lepidopterans moved from the field margin flowers into the bean crop. Overall, these results show that insect pollinators are important for optimising bean yields and an important food security consideration on smallholder farms. Field margin vegetation also provides habitat for flower-visiting insects that pollinate beans. Hence, non-crop habitats merit further research focusing on establishing which field margin species are most important and their capacity to support other ecosystem services such as natural pest regulation

Beneficial insects are associated with botanically rich margins with trees on small farms

Beneficial insect communities on farms are influenced by site- and landscape-level factors, with pollinator and natural enemy populations often associated with semi-natural habitat remnants. They provide ecosystem services essential for all agroecosystems. For smallholders, natural pest regulation may be the only affordable and available option to manage pests. We evaluated the beneficial insect community on smallholder bean farms (Phaseolus vulgaris L.) and its relationship with the plant communities in field margins, including margin trees that are not associated with forest fragments. Using traps, botanical surveys and transect walks, we analysed the relationship between the floral diversity/composition of naturally regenerating field margins, and the beneficial insect abundance/diversity on smallholder farms, and the relationship with crop yield. More flower visits by potential pollinators and increased natural enemy abundance measures in fields with higher plant, and particularly tree, species richness, and these fields also saw improved crop yields. Many of the flower visitors to beans and potential natural enemy guilds also made use of non-crop plants, including pesticidal and medicinal plant species. Selective encouragement of plants delivering multiple benefits to farms can contribute to an ecological intensification approach. However, caution must be employed, as many plants in these systems are introduced species

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Background: Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. // Methods: We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung's disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. // Findings: We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung's disease) from 264 hospitals (89 in high-income countries, 166 in middle-income countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in low-income countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. // Interpretation: Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between low-income, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Dry Method for Preparation of Inulin Biomass as a Feedstock For Ethanol Fermentation

Sisal leaves which constitute only 2% of the sisal plant have been used in the production of pulp and fiber; the remaining 98% which is mostly of the sisal bole is largely regarded as waste. The bole&apos;s high inulin fraction (24-36%) is of particular significance due to its chemical functionality and relative ease of fermentation. utilisationThe objective of this study was to identify properties and pertinent characteristics for developing industrially viable methods of extracting inulin from sisal bole in a readily utilisable form. Inulin was extracted using the dry method &apos;baking&apos;, whereby sisal boles were chopped into chips of defined sizes 1.5-6 cm, before drying at 70 - 150 °C. The dried bole chips were milled to sieved powder of 90-2000 μm. Particle sizes and temperature for total sugars were determined using the dinitrosalicylic (DNS) colorimetric method. Prior to fermentation, the inulin was hydrolysed using sulphuric acid to give a total sugar yield of 5-16% wt/wt depending on drying temperature. In general, high temperatures, e.g. 150 °C led to low sugar recovery (10.3% wt/wt), while low temperatures, e.g. 70 °C gave high sugar recovery (16.3% wt/wt). The fine inulin powder (<250 μm) was richer sugar content (~16%), whereas coarse particles (>400 μm) gave low sugar levels (~9%). The hydrolysed inulin was fermented using Saccharomyces cerevisiae for 57 hours giving consistent ethanol yields depending on initial sugar levels.Les feuilles de Sisal constituant seulement 2% de toute la plante ont été utilisé dans la production des pulpes et fibres, et 98 % du reste constituent le tronc était consudéré comme déchet. Le tronc du Sisal possède une fraction élevée de (24-36 %) d&apos;une importance particulière par ses fonctionnalités chimiques et la facilité relative de fermentation. Cet article parle de l&apos;utilisation du polysaccarose du sisal (Agave Americana) à travers la méthode sèche comme un potential du feedstock pour la production de l&apos;éthanol. Cette étude visait l&apos;identification des proprieties et des caractéristiques pertinantes pour le développement industrielle viable des méthodes d&apos;extraction de l&apos;inulin du tronc du sisal en une forme utilisable. L&apos;extraction de l&apos;inulin par la méthode sèche baking était considérée, par laquelle les troncs de sisal étaient coupés en morceaux de dimensions définies (1.5-6 cm) et séchés à 70-150 °C. Les morceaux séchés étaient moulus pour générer une poudre de 90-2000 μm à l&apos;aide d&apos;un tamis d&apos;analyse. La détermination de différentes dimensions de particules et température des sucres était faite par la méthode colorimétrique dinitrosalicylique (DSN). Avant la fermentation, l&apos;inulin était hydrolysé à l&apos;aide de l&apos;acide sulfurique pour donner un rendement total en sucre de 5 16 % wt/wt sur base de la température de séchage. En général, les températures élevées telle que celle de 150 °C avaient donné un bas recouvrement de sucre (10.3% wt/wt) alors que de températures basses dont 70 °C avaient produit un recouvrement élevé (16.3% wt/wt). La poudre de l&apos;inulin fine (<250 μm) a exhibé un taux élevé de sucre (~16%), alors que les particules grossières (>400 μm) avait donné un taux bas d&apos;environ 9 %. L&apos;inulin hygrolysé était fermenté utilisant le Saccharomyces cerevisiae pendant 57 heures donnant de rendements consistants d&apos;éthanol dépendamment de niveaux initiaux du sucre

Robust controller synthesis for multivariable nonlinear systems with unmeasured disturbances

Chemical Engineering Science595977-986CESC

Social economic factors and malaria transmission in Lower Moshi, Northern Tanzania

Abstract Background For many years social economic status has been used as an indicator to characterize malaria treatment seeking behaviors of communities and their adherence to malaria control programs. The present study was therefore conducted to assess the influence of household social economic status, knowledge, attitude and practice on treatment seeking behaviors, distance to health facilities and vector control measures in the Lower Moshi area, northern Tanzania. Methods A cross-sectional household survey was carried out, a quantitative method was used to collect information from the households, and the household socio-economic status was estimated by employing a household asset-based approach. The structured questionnaire also collected information on malaria knowledge, attitudes and treatment seeking behaviors. Results A total of 197 (68.8% were female) household heads were interviewed. Distance to the health centers influenced malaria treatment seeking behaviors especially for children (P = 0.001) and the number of visits to the health facilities made by the household members (P = 0.001). The head of the households' level of education had an influence on bed-net retreatment (P P Conclusion Distance to the health centre influenced malaria treatment seeking behaviors, and the number of visits made by the household members. In addition, the education level of the household heads played a role in understanding and in the selection of malaria interventions for the households. Increasing the number of health facilities close to rural areas will improve malaria treatment seeking behavior, case management and hence reduce malaria-associated morbidities, especially in high risk groups.</p