Physico-thermal and Pasting Properties of Soy-Melon-Enriched “Gari” Semolina from Cassava.

The physical, thermal and pasting properties of “gari”, a fermented and toasted cassava granule, enriched with 10% full fat soy-melon protein supplements, at different processing stages, were studied.  The stages at which the gari meal was enriched were: after fermentation but before toasting (PRT, soak-mix method) and after toasting (AFT, dry-mix method).  Based on the result of the analysis of the physical properties, the swelling index of the samples decreased from 3.79 for the control sample to a range of 3.15-3.34 for the enriched samples.  Wettability values increased from 49 s for the control sample to about 135-148 s for the enriched gari.  A decrease in porosity from 42% for the control sample to 29.33%-32.33% for the enriched samples relative to their moisture contents was observed in the enriched samples.  Enriched “gari” sample of minimum average particle size (AFT) have the highest angle of repose of 37° while the control sample of maximum average particle size have the lowest angle of repose of 29°.  There was an increase in the degree of penetration by cone penetrometer from 19 mm for the control sample to a range of 22.43-23.90 mm for the enriched samples indicating higher gel strength for the control sample.  On the basis of the thermal properties, there was increase in swelling power and the solubility of all the samples with increase in temperature.  The control “gari” had significantly higher swelling power in a range of 5.17-6.68 g/g compared to that of the enriched samples (4.61-5.27 g/g) between the temperature of 45 and 90℃.  The control sample exhibited higher specific heat capacity of 1.222 kJ/(kg·K) than the enriched samples that ranged between 1.085-1.118 kJ/(kg·K).  On the basis of the pasting properties, the control sample had the highest viscosity of 300.92 RVU while the enriched samples had lower viscositiy.  The enriched samples formed paste at lower temperature 79.20-80.05℃ and took shorter time 3.93-4.07 min to gelatinize.  The enriched “gari” sample exhibited high setback and breakdown viscosity values of indicating that its paste will have lower stability against retrogradation than the un-enriched gari samples. Keywords: Physico-thermal, pasting, toasting, enrichment, soy-melon “gari”&nbsp

Laminar Forced Convective Heat Transfer and Fluid Flow in a Finned Cylindrical Annulus

The purpose of this paper is to numerically investigate the effects of some geometric parameters and flow variables on heat transfer augmentation in annuli with equi-spaced internal longitudinal fins along the external walls. A fully developed flow and a constant thermal boundary condition of uniform heat flux at the walls of the pipe were assumed. Continuity, momentum and energy transport equations were adopted for the solutions of the problem. A Q-BASIC code was written based on the finite difference scheme generated. Numerical experiments were conducted to ascertain the effects of Reynolds number Re, radius ratio, R.R, Prandtl number Pr, fin height H, and pipe inclination, on the rate of heat transfer and fluid flow. The results obtained show that for 50 ≤ Re ≤ 500, total Nusselt number NuT increases with increase in Re while for Re > 500, there was no significant increase in NuT. Nusselt number, average velocity and bulk temperature of the fluid increase with increasingin the range 0° ≤ ≤ 75° but for the range 75°≤  ≤ 90°  the effect is negligible. For R.R > 0.6, the heat transfer was observed to be almost independent of R; therefore for economic purposes, heat exchangers similar to the configuration studied should be run at a low pumping power. A numerical study was done to validate the program by test running it for the finless annuli for similar boundary conditions; the results obtained in the present work show the same trend as that of Kakac and Yucel

Effects of Dissimilar Curing Systems on the Strength and Durability of Recycled PET-Modified Concrete

Since curing remains an essential parameter that directly influences concrete strength and durability, this research aimed at evaluating the effects of water, sodium chloride (NaCl), and sodium carbonate (Na2CO3) curing regimes on concrete’s strength and durability. The design mix was composed of concrete mix ratio of 1:2:4, hydrated ordinary Portland cement with a water/ binder ratio of 0.50, river sand as fine aggregates, and varying percentages of heat-processed waste PET plastics and granite as coarse aggregates. The curing regimes’ performance was assessed by performing tests viz.: split tensile strength, compressive strength, and water absorption tests. The results showed that the curing regimes slightly influenced the split tensile and compressive strength of PET-modified concrete. The 5%-NaCl and 5%-Na2CO3 cured samples, compared to the samples cured in water, gained improved compressive strength values at all curing ages. NaCl curing further led to improved split tensile strengths for the 10 and 20% PET mixes. However, the water cured 20%-PET sample achieved the highest split tensile strength among PET-modified mixes after 28 days. PET-modified concretes attained water absorption percentages within the acceptable limit for normal concrete under the three curing regimes. Statistically, significant correlations and variations were established between the mechanical and durability properties assessed. The study concluded that the NaCl curing technique offers satisfactory performance at 10 and 20% PET replacement levels

Analysis on mechanical properties of AA6061/Rice husk ash composites produced through stir casting technique

fabrication was done by stir casting techniques and the mechanical properties of AA6061/rice husk ash were assessed. The cast were produced with liquid metallurgy route through the reinforcement of 2–8 weight percentages of particle sizes of 75 mm rice husk ash. The microstructural test like SEM/EDS and mechanical properties were studied. From the results, the mechanical properties were found to increase at 8% rice husk ash reinforcement. SEM images revealed that homogenous dispersal of particulates without voids occur in cast and an increase up to 8% rice husk ash revealed substantial blending of matrix and reinforcement as evidenced in the microstructure examinatio

Assessment of Some Clay South West and Aluminmium Dross as Roofing Tile Materials.

Clay has been widely used as a raw material in construction and in the building sector from the ancient period till date. It is a sustainable material and the technology of processing it can be found anywhere in the world. As a result of its sustainability, it can be used in many industries. One of the products derived from clay is roofing tiles. Some of the properties to be considered are thermal and durability of the materials, are necessarily to be taken into consideration, especially if the building needs to be situated in tropical region. Clay seems to be a good choice. This paper will therefore, assess the possibility of using clay from south west and aluminum dross as composite roofing tiles. Clay samples were collected from five (5) deposits in Igboora (Oyo), Ilaro, Itori, Ajegunle in (Ogun) and Ikorodu in (Lagos) states in south west of Nigeria. The clay samples were crushed, pulverized and sieved. Their chemical compositions analysis was carried out using Atomic Absorption Spectrometer (AAS); molds 135mm by 120mm by 15mm were made for the clay samples. Composites were made in the following proportions by a mix of clay samples with aluminum dross in a percentage ratio of 50:50 and another mixture of clay samples with aluminum dross and bentonite as a binder at a percentage ratio of 45:45:10. The physical properties such as water absorption and cold crushing strength were carried out. Also thermal conductivity was carried out on the sample. The result of chemical analysis showed that Igboora, Silica (47.9%) an alumina (36.7%), the rest were the traces or the other element. Ilaro samples were silica (43.5%) and alumina (34.2%) Itori samples, silica (49.8%) and alumina (30.7%). Ajegunle sample, silica (46%) and alumina (38.2%) and Ikorodu sample, silica (54.5%) and alumina (24.6%). These results were compared to the Grim-Shaw specifications which specified (25.45%) alumina and 40.6% silica compositions in requirements for clay soils ascertained that the samples were all clay soils, though the Ikorodu samples was lacking a little in its alumina content. The result of water absorption test of Igboora samples and its composite agree with the Indians roofing tiles’ standard (IS 654:1992) while the other samples failed. The result for Ilaro composite 50:50 had the lowest thermal conductivity of 0.086w/m.kg for the crushing strength test, the Itori and Ilaro composite with bentonite acting as binder produced results of 1.07KN and 1.01KN which agrees with the Indian roofing standard. At this preliminary work, it can be suggested that in conclusion, Igboora and Ilaro clay and their composites seem to be promising for roofing tiles

Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey

Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10 years; 78.2% included were male with a median age of 37 years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020

Approximate Prediction of Chemical Changes in Peanut Oil during Intermittent Deep Frying Process Using UV-Visible Spectroscopy

Aims: The study aimed at predicting some quality changes in peanut oil during intermittent frying of carbohydrate and protein-based foods, using visible spectroscopic and chemometric methods. Study Design:  Completely Randomized Design and Multivariate Linear Regression were used to achieve this study. Place and Duration of Study: The study took place at the Department of Food Science and Technology, Federal University of Technology, Akure between February and September 2017. Methodology: Equal weight of yam chips and marinated chicken [carbohydrate (CHO) and protein-based (PRO) foods, respectively] were fried at 170°C for 20, 40, 60, 80, 100, 120, and 140 min with oil samples taken and topped at every interval. Changes in quality parameters such as colour density, free fatty acid (FFA), acid value (AV), peroxide (PV and saponification values (SV), K-extinction coefficients (K232nm, K266nm,K270nm and K274nm), and ΔK, with time, were determined. UV-Visible spectra (350 – 800 nm) of the oil samples were taken, and the data were elaborated with Principal Component Analysis (PCA) and Partial Least Square (PLS) regression techniques. Results: Reduction in oxidative stability measured as increased values of FFA, PV, K-extinction values and ΔK were observed in all the samples and were particularly more pronounced (p = 0.05) in PRO-fried oils than those of CHO. Similarly, colour density increased linearly as frying time advanced in PRO-fried oil. PCA models of quality and spectra data revealed clear distinctions between PRO and CHO-fried oil samples. PLS regression coefficients showed that FFA (0.95), PV (0.92), SV (0.94), ΔK (0.98) and colour (0.95) were satisfactorily predicted; despite the relatively small sample size (15). Conclusion: Non-destructive spectroscopic quality screening of vegetable oils during frying could facilitate rapid detection of degradation and the extent to which it can be reused. However, a large sample size is required to validate its reliability

Assessment of Nutrient and Storage Stabilizing Potential of Ginger and Garlic on Composite Fruit Smoothies

Aims: The study aimed at demonstrating the influence of natural spices (ginger and garlic) and storage conditions on nutritional, microbial and organoleptic characteristics of composite fruit smoothies. Study Design: Completely Randomized General Factorial Design and Multivariate Pattern Recognition Technique were used to achieve the study. Place and Duration of Study: The study took place at the Department of Food Science and Technology, Federal University of Technology, Akure between January and May 2018. Methodology: Smoothies were produced from the blends of pineapple, watermelon and banana, treated with garlic and ginger, bottled, pasteurized and stored for 21 days to obtain a total of 12 samples and 2 control (prior to storage). Chemical parameters such vitamin C, total phenol, total sugar, moisture and crude fibre contents, titratable acidity, pH, minerals (calcium, sodium, potassium and magnesium), microbiological and sensory qualities were monitored weekly throughout the storage periods. Results: Univariate data analysis results showed type spices as the most significant factor (p = 0.05) with respect to variables considered. There was a decline in vitamin C, titratable acidity and pH as storage time advanced. Total and reducing sugars and oBrix increased with storage while other chemical parameters did not change significantly. Garlic and ginger extracts enhanced microbial stability and contributed to better sensory acceptability of the samples. Principal component analysis (PCA) multivariate model further showed the distinct trends between the impacts of garlic and ginger on the score and loading plots. Smoothies enriched with garlic had comparatively higher TPC, crude fibre, pH, vitamin C, sodium and its ratios with potassium and magnesium, within the first week, total and reducing sugars on the third week. Conversely, ginger enriched smoothies were high in acidity, sensorial scores, magnesium and potassium in the first week of storage and oBrix afterward. Conclusion: Garlic and ginger are potent natural preservatives with additional nutritional benefits that could replace synthetic additives

Discriminative capacities of infrared spectroscopy and e-nose on Turkish olive oils

The potentials of Fourier transform (FT) near- (NIR) and mid-infrared (IR) spectroscopy, and electronic nose (e-nose) on varietal classification of Turkish olive oils were demonstrated. A total of 63 samples were analyzed, comprising Ayvalik, Memecik, and Erkence oils. Spectra were pretreated with standard normal variate and second derivative. Classification models were built with orthogonal partial least square-discriminant analysis (OPLS-DA), considering the single data sets and also the combined FT-NIR-IR spectra. OPLS-DA models were validated both by cross validation and external prediction. All the models gave good results, being the average correct classification percentages in prediction higher than 90% for spectroscopic data and equal to 82% for e-nose data. The combined FT-NIR-IR data set gave the best results in terms of coefficients of determination (0.95 and 0.67). Different e-nose sensors discriminated Ayvalik, Memecik, and Erkence oils, explaining their distinct aromatic profiles

qSUB2: A novel QTL with positive epistasis with SUB1 locus enhances submergence tolerance in rice

Climate change is expected to significantly increase submergence stress of lowland rice (Oryza sativa) production in Africa. There is a need to further improve the ability of SUB1 gene to tolerate submergence stress. Genetic control of submergence tolerance was studied in a moderately tolerant to submergence African rice landrace “TOS6454.” Three mapping populations with a total of 1182 lines were developed by crossing TOS6454 with three popular rice varieties of West Africa that are high-yielding but submergence susceptible, that is, FARO44, FARO52, and FARO60. The screening for submergence was conducted at the Africa Rice Center (AfricaRice) station in Ibadan, Nigeria during 2016–2018. The three mapping populations were genotyped with single nucleotide polymorphic markers either on the Kompetitive allele specific PCR or the DArTseq platforms. Quantitative trait locus (QTL) analysis revealed five different QTLs on chromosomes 1, 2, 3, 4, and 9. The QTLs on chromosomes 2 (qSUB2) and 9 (qSUB9) had consistent large effects and the tolerance alleles were contributed by TOS6454. The QTL on chromosome 9 (qSUB9) had a large effect on submergence tolerance in all three mapping populations. This QTL had a highest logarithm of odds (LOD) score of 30.46 and explained as much as 27.7% phenotypic variation (R2), with an additive effect of up to 9.39. The QTL on chromosome 2 (qSUB2) had a highest LOD score of 10.78 and explained up to 10.8% R2 for this trait. Furthermore, qSUB2 had positive epistasis with qSUB9 which further increased submergence tolerance. A total of 57 lines carrying both qSUB2 and qSUB9 alleles were superior to all other lines in submergence tolerance. qSUB9 co-segregated with ART5 a marker for the SUB1 gene; thus, it is suggested that qSUB9 is the same as the well-known SUB1 gene. Pyramiding qSUB2 with the SUB1 gene locus is expected to further improve submergence tolerance in elite rice varieties