Development of an active evaporative cooling system for short-term storage of fruits and vegetable in a tropical climate

An active evaporative cooler for short-term storage of fruits and vegetable has been developed to improve the shelf life of fruits and vegetables for small holder farmers in Southern Nigeria.  The evaporative cooler uses palm fruit fiber as cooling pad material which is considered a waste in palm oil production in Nigeria and consists of three suction fan, automatic water control switch, water pump and evaporative cooling chambers.  The performance of cooler was evaluated in terms of temperature drop, efficiency of the evaporative cooling and cooling capacity.  The temperature drop ranged from 40C to 130C while the relative humidity of the ambient air was increased to 96.8%.  The cooler could drop the temperature close to wet bulb depression of ambient air and provided up to 98% cooling efficiency with a maximum cooling capacity of 2,529 W.  At an ambient temperature of 370C, the evaporative cooler provided the storage conditions of 23.2 temperature and 85.6% – 96.8% relative humidity, which can enhance the shelf life of wide range of fruit and vegetables of moderate respiration rates.  The power consumption of the cooler was half that of a typical vapour compression refrigerator of the same volume.   Keywords: cooling capacity, cooling efficiency, evaporative cooling, temperature drop cerun:yes'> A throughput capacity of 66.06 kg h-1 was obtained at moisture content of 12.5% wet basis and 405 r min-1 while throughput capacity of treadle thresher was 55.51 kg h-1 at moisture content of 17% wet basis and 610 r min-1.    Keywords: cowpea, mechanical damage, moisture content, threshing efficiency, variet

A Novel Derivatization Ultraviolet Spectrophotometric Method for the Determination of Dihydroartemisinin using p- Nitroaniline

Purpose: To develop a novel ultraviolet (UV)–spectrophotometric method for the determination of dihydroartemisinin (DHA) in tablets using  p-nitroaniline (PNA) as a derivatizing agent.Methods: Derivatization was based on the reaction between methanol solutions of dihydroartemisinin (DHA) and p-nitroaniline (PNA) in acid medium (1M HCI) at elevated temperature and for a short reaction time. Optimal detector response was obtained within 15 min when the reaction was carried out at 90 0C in a molar ratio of 2:1 (DHA:PNA). The method used for analysis was validated and a linear calibration curve constructed in the range of 30 – 100 ìg/mL for the reaction mixture at an absorbanceof 290 nm.Results: Separation of adduct from PNA was better achieved on reversed phase thin layer chromatography (TLC) using acetonitrile : water (60:50) or on high performance liquid chromatography (HPLC) with retention times of 2.8 min for PNA and 5.8 min for the adduct. The limit of detection was 6ìg/mL. The method was precise and accurate in the range 100.70 - 100.96 %, with intraday and interday precisions of less than 2 % at concentrations of 40 and 80 ìg/mL, respectively. The new method was applied to the assay of two brands of dihydroartemisinin tablets with accuracy similar tothat of the International Pharmacopoeia (IP) UV-spectrophotometric method (p > 0.05).Conclusion: The derivatization method is simple, direct, devoid of dilutions and inexpensive in terms of reagent requirements and analyte volume, and has a shorter reaction time, cpmpared with IP method. Based on the foregoing, the method can be adopted as an alternative to the official assay method for routine quality control of dihydroartemisinin tablets.Keywords: Derivatization, Ultraviolet spectrophotometry,  Dihydroartemisinin, p-Nitroaniline, Analysis, Assay, Quality contro

Maternal pneumococcal nasopharyngeal carriage and risk factors for neonatal carriage after the introduction of pneumococcal conjugate vaccines in The Gambia.

OBJECTIVES: Pneumococcal nasopharyngeal carriage occurs early in life. However, the role of vertical transmission is not well understood. The aims of this study were to describe carriage among mothers and their newborns, and to assess for risk factors for neonatal carriage. METHODS: In a nested retrospective cohort study, we analysed data from the control arm of a randomized controlled trial conducted in The Gambia 2 to 3 years after introduction of pneumococcal conjugate vaccine (PCV) 13. Nasopharyngeal swabs were collected from 374 women and their newborns on the day of delivery, then 3, 6, 14 and 28 days later. Pneumococci were isolated and serotyped using conventional microbiologic methods. RESULTS: Carriage increased from 0.3% (1/373) at birth to 37.2% (139/374) at day 28 (p <0.001) among neonates and from 17.1% (64/374) to 24.3% (91/374) (p 0.015) among women. In both groups, PCV13 vaccine-type (VT) serotypes accounted for approximately one-third of the pneumococcal isolates, with serotype 19A being the most common VT. Maternal carriage (adjusted odds ratio (OR) = 2.82; 95% confidence interval (CI), 1.77-4.80), living with other children in the household (adjusted OR = 4.06; 95% CI, 1.90-8.86) and dry season (OR = 1.98; 95% CI, 1.15-3.43) were risk factors for neonatal carriage. Over half (62.6%) of the neonatal carriage was attributable to living with other children in the same household. CONCLUSIONS: Three years after the introduction of PCV in The Gambia, newborns are still rapidly colonized with pneumococcus, including PCV13 VT. Current strategies for pneumococcal control in Africa do not protect this age group beyond the herd effect

ECONOMIC ANALYSIS OF DIFFERENT WOOD SPECIES IN MAJOR SAWMILLS IN ABEOKUTA OGUN STATE NIGERIA

This study involved the economic analysis of different wood species in major sawmills in Abeokuta, Ogun State Nigeria. Two stage design sampling techniques were employed for this study. Descriptive statistics and Cost and Returns were used in the data analysis. Result showed that 62.5% engaged in the business were males, 81.7% were in age group between 31-50years, 48.3% had no formal education, and 88.3% entered into the business through apprenticeship and are mostly full-time. The result also revealed that 95.83% of the saw millers or plank sellers obtain their timber from the private forest and they mostly buy per species i.e. per tree. Moreover, among the timber species that were common in the saw mills include, Albizia coriaria (ayinre) has the highest percentage frequency of 66.7%, Anogeissus leiocarpus (orin dudu) has 44.2%, Cleistopholis sp. (okedo) 32.5% and Musanga cecropioides (aga) 1.7% with the least percentage frequency. Average girth sizes of timber species in sawmill, ranged from 3.00cm- 5.60cm and the average number of plank ranged from 6-29. The business could be seen as profitable, as the cost analysis revealed the average profit for each sawmill per month&nbsp; in Abeokuta North, Odeda and Abeokuta South Local Governments’ Areas to have these profits (₦982,893.75, ₦790,083.524 and ₦790,083.524) respectively. It was recommended that government policy should be reviewed against illegal felling and over-exploitation of timber by imposing/enacting stiffer penalty or law to illegal feller. Government policy should also encourage individual plantation establishment to ensure continuity of forest products for posterity. &nbsp

USPOREDBA PROCJENE EKONOMSKE KORISTI ZEMLJANIH BAZENA RIBNJAKA I BETONSKIH SPREMNIKA U AKVAKULTURNOM PODUZETNIŠTVU DRŽAVE OYO U NIGERIJI

The study focused on the comparative evaluation of economic benefits of earthen fish ponds and concrete tanks in aquaculture enterprises in Ibadan, Oyo state. Primary data were collected with the aid of structured interview schedule, administered through personal interviews and observations to elicit information from 100 fish farmers using purposive and convenience sampling procedure. Data collected were analyzed using descriptive, budgetary and inferential statistics. The study revealed that the mean age, male, married, household size, educated and fish farming experience were 41 years, 83.0%, 87.0%, 5 persons, 96.0% and 8 years, respectively. Earthen fish ponds users earned mean revenue of N3,322,189.85 with gross margin of N2,188,397.89 while concrete tank users earned N2,412,271.08 with gross margin of N1,413,299.46. The results showed profitability indices (0.61 and 0.47), Variable Cost ratio (0.35 and 0.30), Benefit Cost Ratio (2.55 and 1.89), Gross ratio (0.40 and 0.54) and Expenses structure ratio (0.13 and 0.23) for both the earthen ponds and concrete fish tanks, respectively. There were significant differences (t = 42.53, p≤0.05) between the profit level of earthen fish ponds and concrete tanks. Major constraints affecting economic status of the respondents were high cost of quality feed, insufficient funds, poaching and poor marketing channel. In conclusion, aquaculture is a more profitable and viable business regardless of the culture system. Government should assist the fish farmers by subsidizing feeds cost, granting and monitoring of loan.Temelj ovog istraživanja bila je usporedba procjene ekonomske koristi zemljanih bazena ribnjaka i betonskih spremnika u akvakulturnim poduzećima grada Ibadana u državi Oyo. U izboru 100 uzgajivača ribe korištena je kombinacija svrsishodnog i praktičnog uzorkovanja, a uzgajivači su bili podvrgnuti strukturiranom intervjuu radi prikupljanja primarnih podataka u svrhu deskriptivne statistike, proračunske tehnike i inferencijalne statistike. Istraživanje je rezultiralo sljedećim podacima: prosječna životna dob bila je 41 godina, muškaraca je bilo 83,0%, oženjenih 87,0%, u većini slučajeva bilo je 5 članova kućanstva, obrazovanih je bilo 96,0%, a iskustvo uzgoja riba kod ispitanika bilo je 8 godina. Korisnici zemljanih bazena ribnjaka imali su srednji prihod od N3,322,189.85 s bruto maržom od N2,188,397.89, dok su korisnici betonskih spremnika zaradili N2,412,271.08 s bruto maržom od N1,413,299.46. Indeks profitabilnosti bio je 0,61 i 0,47, varijabilni omjer troškova 0,35 i 0,30, omjer troškova i koristi 2,55 i 1,89, bruto omjer 0,40 i 0,54, a omjer strukture troškova bio je 0,13 i 0,23. Značajna je razlika između razine profita od zemljanih ribnjaka i betonskih spremnika (t = 42,53, p ≤ 0,05). Glavne prepreke koje utječu na ekonomski status ispitanika bili su visoki troškovi kvalitetne prehrane, neadekvatnost fondova, krivolov i loš marketing. Zaključno, akvakultura je isplativo i održivo područje poduzetništva, bez obzira na kulturni sustav. Vlada bi trebala pomoći uzgajivačima ribe subvencioniranjem troškova prehrane, odobravanjem i praćenjem kredita

DESIGN AND FABRICATION OF A LOW-COST CENTRIFUGAL HONEY EXTRACTOR

The traditional and screw press techniques were adopted and utilized extensively by Nigerian honey producers and these have led to the absence of a good quality and timely produced honey devoid of foreign materials and marketable by international standard. Ample information from literature survey showed that the Langstroth hive which is beyond the reach of common Nigerian bee farmer due to its high cost. A 750 W indigenous centrifugal honey extractor was developed using locally sourced materials.. The machine was tested at extraction speed levels of 272, 287, 351, 1445, 1730, 2300 and 2575 rpm. Quantifiable extractions were obtained at all speed levels except at a speed of 2575 rpm where a vicious crushed extract of honey and comb was observed. High speed extraction was not favorable as it resulted in the destruction of the honey comb. Honey extracted at the two lower speeds of 272 and 287 rpm were found to be purer with less foreign materials and of high quality.&nbsp; This indigenous centrifugal honey extractor is also favorable for extraction of honey from other types of hives apart from the Langstroth hive and is marketable

DEVELOPMENT OF A VIBRATORY HONEY EXTRACTOR

Extraction of honey from honey comb is extracted predominantly using either traditional method or the mechanical screw press method which generates a problem of crushing the comb along with the extract. This creates an additional cost of separating unwanted materials in the extract. To solve this problem for stakeholders in the honey business worldwide, a vibratory honey extractor was conceived, designed and fabricate. The machine was made of stainless, mild steel and plastic materials. The machine has a capacity of 2.5 Kw and operates at speed and frequency of 483 rpm and 50 Hz respectively. The machine was able to attain an extract of 98.9% a value far better than the centrifugal method within 40 minutes of operation. A reduction to 0.21 of the initial weight of honey extraction was obtained at an average extraction rate of 7.36g /min. The honey extracted was good quality given the best acceptable value for all stakeholders in the honey business industries

Impact of intra-partum azithromycin on carriage of group A streptococcus in the Gambia: a posthoc analysis of a double-blind randomized placebo-controlled trial

Background: Group A Streptococcus (GAS) is a major human pathogen and an important cause of maternal and neonatal sepsis. Asymptomatic bacterial colonization is considered a necessary step towards sepsis. Intra-partum azithromycin may reduce GAS carriage. Methods: A posthoc analysis of a double-blind, placebo-controlled randomized-trial was performed to determine the impact of 2 g oral dose of intra-partum azithromycin on maternal and neonatal GAS carriage and antibiotic resistance. Following screening, 829 mothers were randomized who delivered 843 babies. GAS was determined by obtaining samples from the maternal and newborn nasopharynx, maternal vaginal tract and breastmilk. Whole Genome Sequencing (WGS) of GAS isolates was performed using the Illumina Miseq platform. Results: GAS carriage was lower in the nasopharynx of both mothers and babies and breast milk among participants in the azithromycin arm. No differences in GAS carriage were found between groups in the vaginal tract. The occurrence of azithromycin-resistant GAS was similar in both arms, except for a higher prevalence in the vaginal tract among women in the azithromycin arm. WGS revealed all macrolide-resistant vaginal tract isolates from the azithromycin arm were Streptococcus dysgalactiae subspecies equisimilis expressing Lancefield group A carbohydrate (SDSE(A)) harbouring macrolide resistant genes msr(D) and mef(A). Ten of the 45 GAS isolates (22.2%) were SDSE(A). Conclusions: Oral intra-partum azithromycin reduced GAS carriage among Gambian mothers and neonates however carriage in the maternal vaginal tract was not affected by the intervention due to azithromycin resistant SDSE(A). SDSE(A) resistance must be closely monitored to fully assess the public health impact of intrapartum azithromycin on GAS. Trial registration: ClinicalTrials.gov Identifier: NCT0180094

Molecular epidemiology of pneumococci obtained from Gambian children aged 2–29 months with invasive pneumococcal disease during a trial of a 9-valent pneumococcal conjugate vaccine

BACKGROUND: The study describes the molecular epidemiology of Streptococcus pneumoniae causing invasive disease in Gambian children METHODS: One hundred and thirty-two S. pneumoniae isolates were recovered from children aged 2-29 months during the course of a pneumococcal conjugate vaccine trial conducted in The Gambia of which 131 were characterized by serotyping, antibiotic susceptibility, BOX-PCR and MLST. RESULTS: Twenty-nine different serotypes were identified; serotypes 14, 19A, 12F, 5, 23F, and 1 were common and accounted for 58.3% of all serotypes overall. MLST analysis showed 72 sequence types (STs) of which 46 are novel. eBURST analysis using the stringent 6/7 identical loci definition, grouped the isolates into 17 clonal complexes and 32 singletons. The population structure of the 8 serotype 1 isolates obtained from 4 vaccinated and 2 unvaccinated children were the same (ST 618) except that one (ST3336) of the isolates from an unvaccinated child had a novel ST which is a single locus variant of ST 618. CONCLUSION: We provide the first background data on the genetic structure of S. pneumoniae causing IPD prior to PC7V use in The Gambia. This data will be important for assessing the impact of PC7V in post-vaccine surveillance from The Gambia

Nutritional Composition of a Non-Alcoholic Beverage Spiced with Zingiber officinale Extract Produced from Sorghum bicolor Stem Sheath

Abstract The fo rmulated beverage samples with ginger extract were analysed to determine its nutrient profile: pro ximate and mineral contents. Pro ximate analysis of the spiced stem sheath beverage revealed that the beverage is a nutrient dense commodity with health pro moting substances with high level of protein and fat : the mo isture content ranged between 87.890-88.360%, crude protein ranged between 0.092-0.052% and crude fat fro m 0.190-0.150% while p H and TTA were 7 and 4 respectively. The plain beverage sample had the least protein and fat content. High mineral contents were recorded for the spiced beverage samples: magnesium ranged between 145.00 -220.200mg/ 100ml, sodiu m ranged between 25.200-26.580mg/100ml, potassium ranged between 23.025 -30.950mg/100ml,calciu m 50.000-50.045mg/100ml, iron 4.000-5.340mg/100ml, zinc 2.500-3.170mg/100ml, manganese 0.380-1.730 and copper 0.0605-0.071mg/ 100ml while the plain beverage sample had the least mineral content. The nutrient profile increased significantly at (p &lt; 0.05) with th e addition of ginger, the degree of enhancement was dependent on the concentration of the spice. The overall sensory evaluation revealed that acceptability was in order of 0.5% ext ract of g inger being the best preferred by the panellists