The Role of Statistical Methods and Tools for Weather Forecasting and Modeling

The need to understand the role of statistical methods for the forecasting of climatological parameters cannot be trivialized. This study gives an in depth review on the different variations of the Mann-Kendall (M-K) trend test and how they can be applied, regression techniques (Simple and Multiple), the Angstrom-Prescott model for solar radiation, etc. The study then goes ahead to apply some of them with data obtained from the Nigerian Meteorological Agency (NiMet), and applying tools like the python programming language and Wolfram Mathematica. Results show that the maximum ambient temperature for Calabar is increasing (Z = 2.52) significantly after the calculated p-value <0.05 (significant level). The seasonal M-K test was also applied for the dry and wet seasons and both were found to be increasing (Z = 3.23 and Z = 4.04 respectively) after their calculated p-values <0.05. The relationship between refractivity and other meteorological parameters relating to it was discerned using partial differential equations giving the gradient of each with refractivity; this was compared with results from the correlation matrix to show that the water vapor contents of the atmosphere contributes significantly to the variation of refractivity. Multiple linear regression has also been adopted to give an accurate model for the prediction of refractivity in the region after the residual error between the calculated refractivity and predicted refractivity was minimal

Statistical Modelling of Drying Characteristics of Unripe Plantain (Musa Paradisiaca) Slices

This work is designed to carry out the statistical modelling of the drying characteristics of unripe plantain (Musa paradisiaca) slices and to study the effect of drying temperature and slice thickness on drying characteristics. The test samples were dried in a laboratory scale oven dryer at varying temperatures of 700C, 800C and 900C, and different slice thicknesses of 2mm, 3mm and 4mm.The result obtained indicated that drying temperature and slice thickness had significant effect on drying rate and hence moisture profile. The moisture ratio – drying time data obtained were fitted to ten thin layer drying models. The fit quality obtained with each model was evaluated using statistical tests namely; coefficient of determination (R2), root mean square error (RMSE), reduced chi-square (X2), and standard error of estimate (SEE). Although most of the models fitted quite well to the experimental data, Page and Modified Page models showed the highest average R2 and the lowest average RMSE, X2 and SEE values. Page and modified Page models were selected and found suitable to represent the drying characteristics of unripe plantain slices and predict drying times

Change in Lipid Quality of Tilapia Fish (Oreochromis niloticus) After Different Heat Treatments

Tilapia fish (Oreochomis niloticus) has been considered to be popular among the freshwater fishes, economically cheap and more abundant in Nigeria. For this reason, a study was conducted on the effect of traditional processing methods on fatty acid composition of Oreochomis niloticus using electric oven (control), sawdust, melon husk and rice bran as different heat treatments. Fatty acid composition was determined using standard analytical technique. The result showed that palmitic and oleic acids had the highest concentrations among saturated and unsaturated fatty acids in all the processed samples, respectively. It was also revealed that samples of Oreochomis niloticus recorded decrease in total saturated fatty acid (TSFA) with various heat treatments whereas the same heat treatments enhanced the components of total unsaturated fatty acids (TUFA) and total essential fatty acid (TEFA). It was found that levels of ratio of n–6 PUFA to n–3 PUFA and oleic to linoleic which are used as biomedical index are desirable in all the processed samples of Oreochomis niloticus oils. However, heat treatment using sawdust was proven to be of good economic potential. Keywords: Oreochomis niloticus, agricultural wastes, fatty acids

X-ray crystallographic and structural studies of (benzothiazol-2-yl)ethanesulphonamide, and its antimicrobial properties

N-(benzothiazol-2-yl)ethanesulphonamide (ES2ABT) was synthesized by the condensation of 2-aminobenzothiazole and ethanesulphonylchloride in acetone at 130 °C. The resulting crude precipitates were recrystallized in absolute ethanol. ES2ABT was characterized using X-ray crystallography, mass spectrometry, elemental microanalysis, UV/VIS spectrophotometry, infra red, proton and 13C NMR spectroscopies. The antimicrobial tests of the compound were carried out on both multi-resistant bacterial strains isolated under clinical conditions and cultured species using agar-well diffusion method. The multi-resistant bacterial strains used were Escherichia coli, Proteus species, Pseudomonas aeroginosa and Staphylococcus aureus which were isolated from dogs. The culture species were Pseudomonas aeruginosa (ATCC 27853), Escherichia Coli (ATCC 25922) Staphylococcus aureus (ATCC 25923), and the fungi, Candida krusei (ATCC 6258) and Candida albicans (ATCC 90028). The tests were both in vitro and in vivo. Thus the Inhibition Zone Diameter (IZD), the Minimum Inhibitory Concentration (MIC), and the Lethal and Effective Concentrations (LC50 and EC50) were determined. The antimicrobial activity of the compound was compared with those of Ciprofloxacin and trimethoprim-sulphamethoxazole as antibacterial agents and Fluconazole as an antifungal drug. The compound showed varying activity against the cultured typed bacteria and fungi used. However, ES2ABT was less active than the antibacterial standard drugs used but not Fluconazole which did not show any activity against Candida krusei (ATCC 6258). The Lethal Concentration (LC50) is 338.80 ± 28.6 ppm. This is within the permissible concentrations. Key words: N-(benzothiazol-2-yl)ethanesulphonamide, antimicrobial, in vivo, in vitr

Ouidah et son patrimoine

L'étude sur Ouidah, petite ville de la côte du Bénin, se divise en trois parties. La première présente l'histoire de la cité du 18ème au début du 20ème siècle, les cultes vodouns qui s'y sont développés et le processus d'urbanisation. La 2ème partie inventorie les lieux patrimoniaux qui renvoient à cette histoire et aux traits culturels de cette société. La 3ème dresse un diagnostic des actions et des acteurs dans la ville, rappelle les caractéristiques du patrimoine bâti et propose des mesures pour sa conservation et sa valorisatio

Trypanosoma brucei gambiense group 1 is distinguished by a unique amino acid substitution in the HpHb receptor implicated in human serum resistance

Trypanosoma brucei rhodesiense (Tbr) and T. b. gambiense (Tbg), causative agents of Human African Trypanosomiasis (sleeping sickness) in Africa, have evolved alternative mechanisms of resisting the activity of trypanosome lytic factors (TLFs), components of innate immunity in human serum that protect against infection by other African trypanosomes. In Tbr, lytic activity is suppressed by the Tbr-specific serum-resistance associated (SRA) protein. The mechanism in Tbg is less well understood but has been hypothesized to involve altered activity and expression of haptoglobin haemoglobin receptor (HpHbR). HpHbR has been shown to facilitate internalization of TLF-1 in T.b. brucei (Tbb), a member of the T. brucei species complex that is susceptible to human serum. By evaluating the genetic variability of HpHbR in a comprehensive geographical and taxonomic context, we show that a single substitution that replaces leucine with serine at position 210 is conserved in the most widespread form of Tbg (Tbg group 1) and not found in related taxa, which are either human serum susceptible (Tbb) or known to resist lysis via an alternative mechanism (Tbr and Tbg group 2). We hypothesize that this single substitution contributes to reduced uptake of TLF and thus may play a key role in conferring serum resistance to Tbg group 1. In contrast, similarity in HpHbR sequence among isolates of Tbg group 2 and Tbb/Tbr provides further evidence that human serum resistance in Tbg group 2 is likely independent of HpHbR functio

Assessment of animal African trypanosomiasis (AAT) vulnerability in cattle-owning communities of sub-Saharan Africa

Background: Animal African trypanosomiasis (AAT) is one of the biggest constraints to livestock production and a threat to food security in sub-Saharan Africa. In order to optimise the allocation of resources for AAT control, decision makers need to target geographic areas where control programmes are most likely to be successful and sustainable and select control methods that will maximise the benefits obtained from resources invested. Methods: The overall approach to classifying cattle-owning communities in terms of AAT vulnerability was based on the selection of key variables collected through field surveys in five sub-Saharan Africa countries followed by a formal Multiple Correspondence Analysis (MCA) to identify factors explaining the variations between areas. To categorise the communities in terms of AAT vulnerability profiles, Hierarchical Cluster Analysis (HCA) was performed. Results: Three clusters of community vulnerability profiles were identified based on farmers’ beliefs with respect to trypanosomiasis control within the five countries studied. Cluster 1 communities, mainly identified in Cameroon, reported constant AAT burden, had large trypanosensitive (average herd size = 57) communal grazing cattle herds. Livestock (cattle and small ruminants) were reportedly the primary source of income in the majority of these cattle-owning households (87.0 %). Cluster 2 communities identified mainly in Burkina Faso and Zambia, with some Ethiopian communities had moderate herd sizes (average = 16) and some trypanotolerant breeds (31.7 %) practicing communal grazing. In these communities there were some concerns regarding the development of trypanocide resistance. Crops were the primary income source while communities in this cluster incurred some financial losses due to diminished draft power. The third cluster contained mainly Ugandan and Ethiopian communities which were mixed farmers with smaller herd sizes (average = 8). The costs spent diagnosing and treating AAT were moderate here. Conclusions: Understanding how cattle-owners are affected by AAT and their efforts to manage the disease is critical to the design of suitable locally-adapted control programmes. It is expected that the results could inform priority setting and the development of tailored recommendations for AAT control strategies

How does Trypanosoma equiperdum fit into the Trypanozoon group? A cluster analysis by RAPD and multiplex-endonuclease genotyping approach.

The pathogenic trypanosomes Trypanosoma equiperdum, T. evansi as well as T. brucei are morphologically identical. In horses, these parasites are considered to cause respectively dourine, surra and nagana. Previous molecular attempts to differentiate these species were not successful for T. evansi and T. equiperdum; only T. b. brucei could be differentiated to a certain extent. In this study we analysed 10 T. equiperdum, 8 T. evansi and 4 T. b. brucei using Random Amplified Polymorphic DNA (RAPD) and multiplex-endonuclease fingerprinting, a modified AFLP technique. The results obtained confirm the homogeneity of the T. evansi group tested. The T. b. brucei clustered out in a heterogenous group. For T. equiperdum the situation is more complex: 8 out of 10 T. equiperdum clustered together with the T. evansi group, while 2 T. equiperdum strains were more related to T. b. brucei. Hence, 2 hypotheses can be formulated: (1) only 2 T. equiperdum strains are genuine T. equiperdum causing dourine; all other T. equiperdum strains actually are T. evansi causing surra or (2) T. equiperdum does not exist at all. In that case, the different clinical outcome of horse infections with T. evansi or T. b. brucei is primarily related to the host immune response

Persistent hypertension up to one year postpartum among women with hypertensive disorders in pregnancy in a low-resource setting:A prospective cohort study

BACKGROUND: Hypertensive disorders in pregnancy (HDPs) are associated with lifelong cardiovascular disease risk. Persistent postpartum hypertension in HDPs could suggest progression to chronic hypertension. This phenomenon has not been well examined in low- and middle-income countries (LIMCs), and most previous follow-ups typically last for maximally six weeks postpartum. We assessed the prevalence of persistent hypertension up to one year in women with HDPs in a low resource setting and determined associated risk factors. METHODOLOGY: A prospective cohort study of women conducted at eight tertiary health care facilities in seven states of Nigeria. Four hundred and ten women with any HDP were enrolled within 24 hours of delivery and followed up at intervals until one year postpartum. Descriptive statistics were performed to express the participants’ characteristics. Univariable and multivariable logistic regressions were conducted to identify associated risk factors. RESULTS: Of the 410 women enrolled, 278 were followed up to one year after delivery (follow-up rate 68%). Among women diagnosed with gestational hypertension and pre-eclampsia/eclampsia, 22.3% (95% CI; 8.3–36.3) and 62.1% (95% CI; 52.5–71.9), respectively, had persistent hypertension at six months and this remained similar at one year 22.3% (95% CI; 5.6–54.4) and 61.2% (95% CI; 40.6–77.8). Maternal age and body mass index were significant risk factors for persistent hypertension at one year [aORs = 1.07/year (95% CI; 1.02–1.13) and 1.06/kg/m(2) (95% CI; 1.01–1.10)], respectively. CONCLUSION: This study showed a substantial prevalence of persistent hypertension beyond puerperium. Health systems in LMICs need to be organized to anticipate and maintain postpartum monitoring until blood pressure is normalized, or women referred or discharged to family physicians as appropriate. In particular, attention should be given to women who are obese, and or of higher maternal age

Metabolic syndrome following hypertensive disorders in pregnancy in a low-resource setting:A cohort study

Objectives: Hypertensive disorders in pregnancy (HDPs) are associated with risk of future metabolic syndrome. Despite the huge burden of HDPs in sub-Saharan Africa, this association has not been adequately studied in this population. Study design: This was a prospective cohort study on pregnant women recruited between August 2017 - April 2018 and followed up to one year after their deliveries and evaluated for presence of metabolic syndrome at delivery, nine weeks, six months and one year. Main outcome measures: Prevalence of metabolic syndrome Results: A total of 488 pregnant women were included: 410 and 78 with HDPs and normotensive, respectively. None of the normotensive had metabolic syndrome until one year (1.7% = 1 out of 59 observations), while among those with HDPs were 17.4% (71 of 407), 8.7% (23 of 263), 4.7% (11 of 232) and 6.1% (17 of 278), at delivery, nine weeks, six months and one year postpartum, respectively. High BMI and blood pressure were the drivers of metabolic syndrome in this population. The incidence rate in HDPs versus normotensive at one year were, respectively, 57.5/1000 persons’ year (95%CI; 35.8 – 92.6) and 16.9/1000 persons’ years (95%CI; 2.4-118.3), with incidence rate ratio of 3.4/1000 person's years. Only parity significantly predicted the presence of metabolic syndrome at one year [(aOR= 3.26/delivery (95%CI; 1.21-8.79)]. Conclusion: HDPs were associated with a higher incidence of metabolic syndrome up to one year postpartum. Women with HDPs should be routinely screened for metabolic syndrome within the first year postpartum to reduce cardiometabolic risks.</p