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Tea contains high content of phenolics which are well-known to act as antioxidants. As such, there are claims that the consumption of infusion of tea could help ameliorate free radical-induced diseases; this therapeutic activity would depend on the amount of phenolics that is soluble and the amount that is absorbed and available for metabolic activity when consumed. The purpose of this study is to analyze the content of phenolics and antioxidant activity of some health tea and also to study the effect of addition of sugar and milk on in-vitro availability of phenolics in tea, cocoa and coffee drinks.

Seven brands of health tea, two brands of cocoa drink, one brand each of coffee, powdered milk and sugar were selected. The tea samples were analyzed for pH, titratable acidity, total phenol and antioxidant activity using Folin–Ciocalteau and 202-diphenyl-1-picryl-hydrazil 28DPPH-29-20 reagents. In-vitro simulated digestion modeling stomach and small intestine were carried out on tea infusion, coffee and cocoa drinks with or without sugar, and phenolic availability was analyzed.

The result indicated that pH, titratable acidity and total phenolics ranged from 4.5 to 5.6, 0.167 to 0.837 (as maleic acid) and 1.15 to 1.17 mg/g gallic acid equivalent, respectively. Black tea recorded the highest phenolic content, in-vitro phenolic availability and antioxidant activity. Addition of sugar to black tea and chocolate drink caused a significant decrease in the in-vitro available phenolics, while the addition of milk leads to a significant enhancement.

The data obtained in this study can be used nutritionally and commercially to show the impact of adding sugar or milk on the content of phenolics and their bioavailability in-vitro. The study justifies the claim that tea could help ameliorate free radical-induced health defects.

Assessment of antioxidant activity of food should not be based only on the content of total phenolics but on the amount that is bioavailable in the body system when the food is consumed.

Consumption of tea, cocoa and coffee drinks with milk and sugar have been found to enhance or inhibit phenolics. Therefore, the optimum level of these additives should be determined if the drinks were meant for therapeutic purposes.

Results obtained may provide some useful information for considering the bioavailability of phenolics present in tea and beverages in view of consumption/digestion in our body as well as interference of sugar and milk as the additives.

This paper presents experiment results that examine the validity of extracting blade vibration signature from the shaft torsional vibration signals. A special test rig was designed and manufactured for this objective. A set of strain gages were bonded to the shaft and to the blades to measure the shaft twisting and blade bending deformations respectively. A controlled frequency exciter excited the blade vibration. The shaft torsional and blade bending vibration signals were simultaneously recorded and presented in the time and frequency domains. The blade bending vibration frequencies appeared dominantly in the shaft torsional vibration signals for all blade vibration frequencies up to 100Hz. For frequencies higher than 100Hz, less sensitivity of the torsional vibration to blade vibration was observed.

The purpose of this paper is to present a method for early crack detection in rotating shafts. A rotor-bearing system, consisting of an elastic rotor mounted on fluid film bearings, is used to detect the presence of the crack at a depth of around 5 percent of shaft radius. The fluid film bearings, the shaft and the crack introduce coupled bending vibrations both in the horizontal and vertical plane. Experimental time series of the rotor composite response under normal steady-state operation are uncoupled, to develop a signal processing procedure able to reveal the presence of the crack.

The variation of the coupling property that a crack (breathing or not) or a cut (always open) introduces into the system and the localization of the coupling in the time domain is a concept proposed as a means to detect transverse surface cracks in rotating shafts. This consideration is combined with the concept of external excitation for the development of an additional crack-sensitive response during system normal operation. Using an external excitation of an active magnetic bearing of specific duration, frequency and amplitude, the method uses this coupling variation during rotation.

The method is simple, quick and effective for early crack detection, being able to detect cracks as shallow as 5 percent of the shaft radius while the system is under normal operation, and can even be applied real-time. Experimental verification uses a simple elastic rotor with a cut mounted on fluid film bearings, with the cut producing similar coupling phenomena as an opened crack. Experimental results are encouraging.

The method used is simple, quick and effective for early crack detection, being able to detect cracks as shallow as 5 percent of the shaft radius while the system is under normal operation, and can even be applied real-time.

Many incidents of rotor failures are reported due to the development and propagation of the crack. Condition monitoring is adopted for the identification of symptoms of the crack at very early stage in the rotating machinery. Identification requires a reliable and accurate vibration analysis technique for achieving the objective of the study. The purpose of this paper is to detect the crack in the rotating machinery by measuring vibration parameters at different measurement locations.

Two different types of cracks were simulated in these experiments. Experiments were conducted using healthy shaft, crack simulated shaft and glued shaft with and without added unbalance to observe the changes in vibration pattern, magnitude and phase. Deviation in vibration response allows the identification of crack and its location. Initial data were acquired in the form of time waveform. Run-up and coast-down measurements were taken to find the critical speed. The wavelet packet energy analysis technique was used to get better localization in time and frequency zone.

The presence of crack changes the dynamic behavior of the rotor. 1× and 2× harmonic components for steady-state test and critical speed for transient test are important parameters in condition monitoring to detect the crack. To separate the 1× and 2× harmonic component in the different wavelet packets, original signal is decomposed in nine levels. Wavelet packet energy analysis is carried out to find the intensity of the signal due to simulated crack.

Original signals obtained from the experiment test set up may contain noise component and dominant frequency components other than the crack. Wavelet packets contain the crack-related information that are identified and separated in this study. This technique develops the condition monitoring procedure more specific about the type of the fault and accurate due to the separation of specific fault features in different wavelet packets. From the experiment end results, it is found that there is significant rise in a 2× energy component due to crack in the shaft. The intensity of a 1× energy component depends upon the shaft crack and unbalance orientation angle.

Neuromyelitis Optica Spectrum Disorder (NMOSD) is a rare disease with unknown risk factors. The role of oxidative stress and nutritional factors is imprecise in NMOSD development. Therefore, this paper aims to evaluate the effects of dietary total antioxidant capacity (TAC) on the odds of NMOSD.

Dietary TAC was determined in 70 definite NMOSD cases and 164 healthy controls in term of Ferric Reducing Antioxidant Power (FRAP) method. A validated 168-item semi-quantitative food frequency questionnaire (FFQ) was used for dietary assessment. Three multivariate regression models were applied to analyze the odds of NMOSD across the TAC quartiles.

A significant inverse association was found between dietary TAC and odds of being assigned to the NMOSD group in all three regression models. In the fully adjusted model ORs (95% CI) in the second, third and fourth quartiles of TAC vs the first quartile were as follows: 0.11 (0.04-0.29), 0.05 (0.01-0.16) and 0.01 (0.00-0.05), respectively. Odds of NMOSD also indicated a significant decreasing trend across the quartiles of dietary TAC (p-trend: <0.01). Total energy (p < 0.01) as well as consumption of vegetables (p < 0.01), whole grains (p < 0.01), tea and coffee (p < 0.01), legumes (p < 0.01) and poultry (p < 0.01) significantly increased through the TAC quartiles.

In the present study, a new hypothesis was proposed concerning the influence of dietary TAC on the odds of NMOSD. A diet rich in foods with high TAC can be effective in the modification of the NMOSD odds.

Ọsẹ dúdú production and sale constitute a major indigenous business among the Yoruba people. Scholars have noted that the business is capable of boosting the socio-economic status of black soap entrepreneurs and of countries. However, ọsẹ dúdú enterprise has some significant threats and problems that are yet to be researched. This chapter examined the challenges of osẹ dúdú entrepreneurs in Southwest Nigeria. Twenty-six interviews were conducted among indigenous black soap producers and sellers in Ogun, Oyo and Lagos States. Data were analysed in themes. Weather, financial, spiritual, copyright and succession challenges, as well as issues such as a large number of sellers, debt, lack of support, pricing and brand competition, were found to be problems faced by black soap entrepreneurs. This chapter concluded that certain controllable and uncontrollable factors were not only capable of limiting the development of osẹ dúdú business but also have adverse implications for the achievement of the sustainable development goals through the indigenous resource. This chapter suggests that osẹ dúdú business actors such as mechanical engineers, local fabricators, financial institutions, and governmental and non-governmental agencies collaborate with black soap entrepreneurs to ameliorate the challenges of the latter. It is only through this alliance that black soap entrepreneurs can contribute to indigenous business development and the achievement of sustainable development goals in Africa.

The purpose of this paper is to develop poundmix for reconstitution, such as pounded yam, from yam, cocoyam and breadfruit blends and to evaluate their nutritional compositions.

Pregelatinized flours of yam, cocoyam and breadfruit were prepared separately. Three coded samples of 30, 40 and 50 per cent composite blends of poundmix were formulated. The proximate composition, starch, vitamin C and mineral elements contents of the poundmix were determined and the results were subjected to statistical analysis.

The protein contents of poundmix samples were 5.6, 6.1 and 6.2 per cent for 30, 40 and 50 per cent composites, respectively, which is an increase from that of whole yam (4.8 per cent). Significant difference also existed between the starch content of the poundmix and that of the whole yam flour (p<0.05). However, there is no significant difference in the overall acceptability of the poundmix samples and that of the whole yam flour at p<0.05.

The paper's findings show that supplementing poundo yam at 40 per cent composite level has the best nutritional composition and organoleptic scores and so it is recommended for both household and industrial practice.

Africa's history of trade, production and financial services that propelled the continent's economic systems existed long before an era of colonisation commonly recognised as beginning in the nineteenth century. By the time the decolonisation of a majority of African countries was achieved in the mid-twentieth century, the African economic identity had been, to a great extent, relegated by Westernised methods and orientations. Today, Indigenous practices are once again resurfacing in Africa's ongoing search for sustainable development, with increasing calls to resuscitate and incorporate these age-long business orientations. This introductory chapter provides readers with a synopsis of all the themes of this second of a two-volume edited book with a focus on the philosophies and practices of Indigenous businesses, which, if successfully explored and scaled up, would make significant contributions to Africa's economic infrastructure.

The Igbo people of south-eastern Nigeria are generally acknowledged as traders and astute entrepreneurs. Extant literature has investigated the various indigenous practices of Igbo entrepreneurs that ensure business success. Despite these efforts, knowledge of their financial practices has been limited. This chapter provides insights on the financial practices that are common amongst Igbo micro-entrepreneurs and the immense benefits of the practices. To unravel these practices, in-depth interviews were conducted with 15 micro-entrepreneurs involved in supermarket, spare parts and food items businesses in Lagos, Nigeria. Using a grounded theory approach, four significant financial practices such as rotating financial contribution, deferred financial arrangements, financial settlement practice and financial prudence common among the Igbo micro-entrepreneurs were identified. Based on the findings, relevant recommendations were made for financial educators and the management of modern financial institutions to adapt and incorporate some of these indigenous financial practices in teaching curricula and financial product designs.

To investigate the potential food, feed and industrial values of some tropical underutilized medicinal plant materials.

Dry‐milled plants, namely: Gongronema latifolium and Vernonia amygdalina were subjected to chemical analysis to determine their proximate, mineral, elemental, fatty acid and amino acid compositions using standard procedures.

Results show that the lipid extract, ash, crude fibre and nitrogen free extractives, oxalate, phytate and tannin of the plants are within expected ranges. They however had unexpectedly high crude protein content: 27.20 and 21.69 per cent, respectively. Potassium, phosphorus, calcium and cobalt were the most abundant mineral elements. G. latifolium and V. amygdalina leaf oils are 50.22 and 24.54 per cent saturated; 39.38 and 65.45 per cent polyunsaturated, respectively. Palmitic and oleic acids were the major monounsaturated fatty acids. Degrees of unsaturation are 0.46 and 0.41, respectively. Major essential amino acids are leucine, valine and phenylalanine. Proportions of essential to non‐essential amino acid are 43.37 and 49.84 per cent, respectively.

The nutritional composition of the plant materials suggests that they may find use in food/feed formulation operations and as industrial raw materials.