Effect of tuber skin on the thermal properties of whole tubers of potato and sweet potato

Temperature-dependent thermal coefficients of mathematical models of the postharvest storage process play an important role in determining the models accuracy. Thermal properties of tubers under storage available in literature are generally of those in semi processed form (skinless) such as those having undergone peeling, dicing and cutting actions. This study investigates the effect of tuber skin on the thermal properties of whole tubers of potato and sweet potato. A direct approach was used to measure the tubers' density and thermal conductivity and thermal diffusivity by the transient heat transfer method. Indirect approach was used to measure the tubers' specific heat. Experimental data were used to develop empirical models of the thermal coefficients as a function of temperature. Results of the study should find great use in the modeling of potato and sweet potato storage process

INFLUENCE OF SEX RATIO ON THE NUTRIENT COMPOSITION OF THE ACCESSORY GLAND AND FEMORAL MUSCLE OF ADULT MALE Zonocerus variegatus

Zonocerus variegatus (L.) is the main grasshopper pest of crops in over twenty countries which occupy the extensive forest and savannah areas of West and Central Africa. It feeds on many plant species, including a wide range of plantation and subsistence crops (Notably cassava, Manihot esculenta leaves) and horticultural plants. Male grasshoppers are smaller than females, and size varies greatly between species-from a length of 0.4 in (1cm) to more than 5.9 in (15 cm). a male grasshopper has a pair of adjacent testes, which appear to be a single structure along the dorsal midline. The testes are made up of many follicles collected by tiny tubes to either the right or left vas deferens. The vas deference carry sperm to the ejaculatory duct. A pair of tiny seminal vesiclesª¤? produces a liquid that combines with the sperm produced in the testes. During mating, there is transfer of secretion from the male to the female, such secretion include protein, lipids and glucose, others may be amino acids, peptides and prostaglandins. Zonocerus variegates is very high in protein concentration and these proteins are transferred during copulation from males to females. The analysis of the mineral concentration of the femoral muscle and accessory glands shows that sodium ion (Na+) has the highest concentration in the femoral muscle and accessory gland of Adult male Z. variegates. Chloride ion (C1-) also has relative high mineral content when compared to other mineral found in the femoral muscle and accessory gland of Z. variegatu

A review: Intelligent controllers for tropical food storage system

Food security can be assured by improving on post harvest storage methods. Food stored under improper storage conditions are prone to increased respiration and transpiration processes which often result in depletion and weight loss of edible material. Storage temperature and relative humidity are major factors that ultimately determine product quality and quantity. This paper presents a survey on methods of post harvest storage systems. The indigenous methods of tropical food storage common to the West African region are discussed. The attendant problems associated with these methods are highlighted. Intelligent control methods are also discussed. A novel intelligent controller is proposed to sustain product quality and quantity by optimizing the storage process

Natural Convection Heat Transfer and Entropy Generation Analysis in Saltbox Roof under Summer Conditions

This study investigates numerically the 2D laminar natural convection in a Saltbox roof type geometry under summer climate conditions as obtained in Africa, particularly Nigeria using ANSYS FLUENT to model the boundary conditions. The effects of Rayleigh number (Ra) within the range of 103-107 and pitch angles (top and base) on heat transfer, the flow structure, temperature distribution and entropy generation within the geometry were analysed. Results show that the flow is nearly symmetric at lower Ra, while for higher Ra, the flow becomes asymmetric. The Nusselt number (Nu) has a proportional relationship with the top pitch angle and an inverse relationship with the base pitch angle when the Rayleigh number is fixed. The effect of the Ra on the Nu is insignificant at lower Ra, but becomes noticeable at higher Ra. The total entropy generation increases with an increase in top pitch angle and a decrease in base pitch angles, at fixed Rayleigh numbers. The physical implication is that, for a Saltbox roof type geometry, at fixed Ra, the best convective heat transfer process is achieved by lowering the base pitch angle and increasing the top pitch angle

Long-term cognitive outcomes in tuberous sclerosis complex.

AIM: To investigate the interdependence between risk factors associated with long-term intellectual development in individuals with tuberous sclerosis complex (TSC). METHOD: The Tuberous Sclerosis 2000 Study is a prospective longitudinal study of individuals with TSC. In phase 1 of the study, baseline measures of intellectual ability, epilepsy, cortical tuber load, and mutation were obtained for 125 children (63 females, 62 males; median age=39mo). In phase 2, at an average of 8 years later, intellectual abilities were estimated for 88 participants with TSC and 35 unaffected siblings. Structural equation modelling was used to determine the risk pathways from genetic mutation through to IQ at phase 2. RESULTS: Intellectual disability was present in 57% of individuals with TSC. Individuals without intellectual disability had significantly lower mean IQ compared to unaffected siblings, supporting specific genetic factors associated with intellectual impairment. Individuals with TSC who had a slower gain in IQ from infancy to middle childhood were younger at seizure onset and had increased infant seizure severity. Structural equation modelling indicated indirect pathways from genetic mutation, to tuber count, to seizure severity in infancy, through to IQ in middle childhood and adolescence. INTERPRETATION: Early-onset and severe epilepsy in the first 2 years of life are associated with increased risk of long-term intellectual disability in individuals with TSC, emphasizing the importance of early and effective treatment or prevention of epilepsy. WHAT THIS PAPER ADDS: Intellectual disability was present in 57% of individuals with tuberous sclerosis complex (TSC). Those with TSC without intellectual disability had significantly lower mean IQ compared to unaffected siblings. Earlier onset and greater severity of seizures in the first 2 years were observed in individuals with a slower gain in intellectual ability. Risk pathways through seizures in the first 2 years predict long-term cognitive outcomes in individuals with TSC

Recurrent oral squamous papilloma in a pediatric patient: Case report and review of the literature

Squamous papillomas are common lesions of the oral mucosa. They are benign proliferating lesions often painless, slow growing and with a cauliflower appearance. However, its clinical appearance which sometimes mimics exophytic carcinoma, verrucous carcinoma or condyloma acuminatum raises concern when it occurs in the oral cavity. Squamous papilloma occurs predominantly in 30‑ to 50‑year old’s. However, they may be seen in children <10 years and accounted for 8% of all oral tumors in children. There is no sex predilection. It has a predilection for the tongue and soft palate, but may occur on any other surface of the oral cavity. Oral squamous papillomas have been associated with infection by the human papilloma virus (HPV). The present report is a case of a recurrent squamous papilloma of the hard palate in a 5‑year‑old patient with a review of the literature.Keywords: HPV,oral cavity, pediatric, squamous papillom

Effect of tuber skin on the thermal properties of whole tubers of potato and sweet potato

Temperature-dependent thermal coefficients of mathematical models of the postharvest storage process play an important role in determining the models accuracy. Thermal properties of tubers under storage available in literature are generally of those in semi processed form (skinless) such as those having undergone peeling, dicing and cutting actions. This study investigates the effect of tuber skin on the thermal properties of whole tubers of potato and sweet potato. A direct approach was used to measure the tubers' density and thermal conductivity and thermal diffusivity by the transient heat transfer method. Indirect approach was used to measure the tubers' specific heat. Experimental data were used to develop empirical models of the thermal coefficients as a function of temperature. Results of the study should find great use in the modeling of potato and sweet potato storage process

Numerical Forced Convection Heat Transfer, Fluid Flow and Entropy Generation Analyses of Al2O3-Water Nanofluid in Elliptical Channels

This study investigates a three-dimensional elliptical microchannel heat sink for heat dissipation in laminar forced convection. The study seeks to improve thermal performance and overcome overheating associated with excessive temperature commonly experienced in heat-generating equipment, which is beyond the temperature usually specified by the manufacturer. The objective of the study is to evaluate the heat transfer, fluid flow, and entropy generation characteristics of Al2O3-water nanofluid in an elliptical cooling channel. The numerical analysis is investigated on the structure experiencing constant volumetric heat generation. The parameters considered are Reynolds number of 100 ≤ Re ≤ 500, nanoparticle concentration ϕ, from 0% to 4% with channel aspect ratio Ar from 1 to 3. The impacts of these parameters on the maximum temperature, heat transfer coefficient, friction factor, and volumetric entropy generation are reported. The study demonstrates that heat transfer is enhanced in the elliptical cooling channel at different aspect ratios, nanoparticle concentrations, and Reynold numbers. The results showed that as the nanoparticle concentration, channel aspect ratio, and Reynolds number (Re) increase, the maximum temperature, and total entropy generation decrease. As the channel aspect ratio increases at a specified Re = 200 and nanofluid concentration, ɸ = 3%, the maximum temperature, and total entropy generation decrease by up to 62% while the heat transfer coefficient increases by up to 78% and the friction factor increase by less than 2% with aspect ratio. However, the friction factor is not sensitive to the nanofluid concentration as a coolant