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Soil fertility has been declining in many parts of Ethiopia, moreover limits agricultural production, sustainability and food security. Nutrient balance is used to evaluate the state of soil fertility, rate of nutrient depletion, sustainability of land productivity, as well as to take the appropriate management decisions. This study was conducted to quantify soil nutrient balance and stocks on smallholder farms at Agew Mariam watershed, in northern Ethiopia in the 2020/21 season. The inflows-outflows of NPK into, and out of barley, tef, and wheat farms were determined through, field measurement, laboratory analysis and interviews. The nutrient balance in each crop was quantified by subtracting nutrient outputs from the inputs. The N partial balance of barley, tef and wheat was −66, −9.8, and −50.7 kg ha−1 yr−1fields, respectively. The P balance was also −5.9, 0.9, and −2.6 kg ha−1 yr−1 for barley, tef, and wheat fields, respectively. The K balance was −12.3, −3.2, and −5.4 kg ha−1 yr−1 in barley, tef, and wheat fields, respectively. The analysis revealed that N, P, and K had negative values except for P in tef. The stock of N was 1295, 1510, and 1240 in barley, tef, and wheat kg ha−1fields, respectively. The P stock was 63, 18.7, and 27.5 kg ha−1 in barley, tef, and wheat farms, respectively. Similarly, K stock was 1092.7, 1059.4, and 1090.6 kg ha−1 in barley, tef, and wheat cropping systems, respectively. Reversing the imbalance between inflows and outflows via adding organic and inorganic fertilizer is essential for barley, tef, and wheat cropping systems in the study area.

Varieties of a single crop type may vary in several attributes affecting the choice at different spots of the food supply chain. This paper demonstrates a rapid classification of ten tef [Eragrostis tef (Zucc.) Trotter] grain varieties based on image processing and multivariate data analysis. Extreme Gradient Boosted Tree Discriminant Analysis (EGBDA) was applied for the variety-based classification. The developed classification model achieved a remarkable classification performance with 97% of prediction accuracy and 99% of precision. A less complex classification model using eighteen selected variables also achieved similar classification performance. The developed technique can authenticate tef varieties at the research and industrial level. Although the finding of this study is remarkable, it is essential to incorporate additional tef varieties into the model and consider other sources of variation such as agroecology as an extension of this finding.

Tef is one of the most important staple cereal crops in Ethiopia. However, the production and productivity of the crop remain low due to lack of appropriate agronomic recommendations. Lack of optimum sowing methods and seed rates are key agronomic factors limit the productivities of the crop. Hence, field experiment was conducted to study the effects of seed rates and sowing methods on growth, yield and yield components of tef. The treatments contains factorial combination of two sowing methods (row and broadcast) and five seeding rates (5, 7.5,10, 12.5, and 15 kg ha−1in randomized factorial complete block design with three replications. Days to heading, days to maturity, plant height, spike length, total number of tiller, total number of effective tiller, above ground dry biomass yield, grain yield and straw yield collected and subjected to analysis of variance using SAS system. The main effect seed rate significantly affect days to physiological maturity, plant height, panicle length, and straw yield and the maximum values of these parameters were recorded at the seed rate of 5 kg ha−1. Similarly, number of total tillers, fertile tillers, total biomass, grain yield, and lodging percent were significantly (p < 0.05) influenced by interaction effect of sowing methods and seeding rates. The highest grain yield (2.301 kg/ha) and other growth parameters recorded at the interaction effect of 5 kg ha−1 of seed rate and row planting method compared to other treatments. Maximum net benefit (795,689.21ETB) with acceptable marginal rate of return (104.32) also recorded at the interaction effect of 5 kg ha−1 of seeding rate and row planting. Hence, 5 kg ha−1 seed rate with row planting method could be recommended for maximum yield of tef in Adet soil and climatic conditions.

This study evaluated the effect of inclusion of two types of tef flours (white and brown) at different levels (25, 50 and 100 %, total flour) on the nutritional (proximal and mineral composition), in vitro bioactive (antioxidant capacity and starch digestibility) and sensory properties of rice-tef crackers. The aim was to formulate a gluten-free product with nutritional and healthy benefits, and acceptable for consumers. Results showed than crackers enriched with white tef had a significant (p ≤ 0.05) higher concentration of all the minerals tested, except for calcium and manganese, compared to brown tef. Iron content of white tef was almost twice that of brown tef, and copper and magnesium increased from 0.12 mg/100 g and 39.2 mg/100 g in control crackers to 0.56 mg/100 g and 197 mg/100 g in white tef crackers (WT 100%), respectively. Moreover, white tef flour and crackers showed significantly higher antioxidant activity than rice or brown tef counterparts. Formulation with tef flour significantly contributed to a reduction of the rapidly available glucose and rapidly digestible starch of crackers.

This paper suggests a nonlinear controller of a Static Synchronous Series Compensator (SSSC) and a doubly-fed induction generator (DFIG) for transient stability enhancement by transient energy function (TEF) technique and super-twisting differentiator in the multi-machine power system. Initially, the TEF approach is employed to damping control and stability enhancement in a multi-machine power system including an SSSC, DFIG, and synchronous generator (SG). Then, the signals of time-derivative in the controller with a super-twisting differentiator are estimated. The significance and novelty of this work are the employs of the TEF method obtained for the multi-machine power system containing DFIG and SG. Another novelty is the use of the DFIG and SSSC simultaneous control whose uncertain parameters are estimated with a super-twisting differentiator. The feature of the nonlinear control approach is robust versus modifications in the topology of the system. Simulation is performed on the IEEE 9-bus system to appraise the operation of the nonlinear controller approach compared to back-stepping and sliding mode control. The simulation results demonstrate that the nonlinear controller approach satisfactorily reduces the first swing of oscillations., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 ISA. Published by Elsevier Ltd. All rights reserved.)

Non-dioxin like polychlorinated biphenyls (NDL PCB) are recognized neurotoxicants with implications on altered neurodevelopment and neurodegeneration in exposed organisms. NDL PCB neurotoxic relative potency schemes have been developed for a single mechanism, namely activity toward the ryanodine receptor (RyR), or combined mechanisms including, but not limited to, alterations of RyR and dopaminergic pathways. We compared the applicability of the two neurotoxic equivalency (NEQ) schemes and applied each scheme to PCB mixtures found in environmental and human serum samples. A multiple mechanistic NEQ predicts higher neurotoxic exposure concentrations as compared to a scheme based on the RyR alone. Predictions based on PCB ortho categorization, versus homologue categorization, lead to a higher prediction of neurotoxic exposure concentrations, especially for the mMOA. The application of the NEQ schemes to PCB concentration data suggests that PCBs found in fish from US lakes represent a considerable NEQ exposure to fish consuming individuals, that indoor air of schools contained high NEQ concentrations representing an exposure concern when inhaled by children, and that levels already detected in the serum of adults and children may contribute to neurotoxicity. With further validation and in vivo exposure data the NEQ scheme would help provide a more inclusive measure of risk presented by PCB mixtures., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Iron deficiency is a major public health concern in Ethiopia, where the traditional diet is based on tef injera. Iron absorption from injera is low due to its high phytic acid (PA) content., Objectives: We investigated ways to increase iron absorption from FeSO4-fortified tef injera in normal-weight healthy women (aged 21-29 y)., Methods: Study A (n = 22) investigated the influence on fractional iron absorption (FIA) from FeSO4-fortified injera of 1) replacing 10% tef flour with whole wheat flour (a source of wheat phytase), or 2) adding an isolated phytase from Aspergillus niger. Study B (n = 18) investigated the influence on FIA of replacing FeSO4 in tef injera with different amounts of NaFeEDTA. In both studies, the iron fortificants were labeled with stable isotopes and FIA was calculated from erythrocyte incorporation of stable iron isotopes 14 d after administration., Results: In study A, the median (IQR) FIA from the 100% tef injera meal was 1.5% (0.7-2.8%). This increased significantly (P < 0.05) to 5.3% (2.4-7.1%) on addition of 10% whole wheat flour, and to 3.6% (1.6-6.2%) on addition of A. niger phytase. PA content of the 3 meals was 0.62, 0.20, and 0.02 g/meal, respectively. In study B, the median (IQR) FIA from the 100% tef injera meal was 3.3% (1.1-4.4%) and did not change significantly (P > 0.05) on replacing 50% or 75% of FeSO4 with NaFeEDTA., Conclusions: FIA from tef injera by young women was very low. NaFeEDTA was ineffective at increasing iron absorption, presumably due to the relatively low EDTA:Fe molar ratios. Phytate degradation, however, greatly increased during tef fermentation on addition of native or isolated phytases. Replacing 10% tef with whole wheat flour during injera fermentation tripled FIA in young women and should be considered as a potential strategy to improve iron status in Ethiopia., (Copyright © The Author(s) on behalf of the American Society for Nutrition 2020.)

Azaspiracids (AZAs) are marine algal toxins that can be accumulated by edible shellfish to cause a foodborne gastrointestinal poisoning in humans. In the European Union, only AZA1, -2 and -3 are currently regulated and their concentration in shellfish is determined through their toxic equivalency factors (TEFs) derived from the intraperitoneal lethal potency in mice. Nevertheless, considering the potential human exposure by oral route, AZAs TEFs should be calculated by comparative oral toxicity data. Thus, the acute oral toxicity of AZA1, -2 and -3 was investigated in female CD-1 mice treated with different doses (AZA1: 135-1100μg/kg; AZA2 and AZA3: 300-1100μg/kg) and sacrificed after 24h or 14days. TEFs derived from the median lethal doses (LD 50 ) were 1.0, 0.7 and 0.5, respectively for AZA1, -2 and -3. In fact, after 24h from gavage administration, LD 50s were 443μg/kg (AZA1; 95% CL: 350-561μg/kg), 626μg/kg (AZA2; 95% CL: 430-911μg/kg) and 875μg/kg (AZA3; 95% CL: 757-1010μg/kg). Mice dead more than 5h after the treatment or those sacrificed after 24h (doses: ≥175μg AZA1/kg, ≥500μg AZA2/kg and ≥600μg AZA3/kg) showed enlarged pale liver, while increased serum markers of liver alteration were recorded even at the lowest doses. Blood chemistry revealed significantly increased serum levels of K + ions (≥500mg/kg), whereas light microscopy showed tissue changes in the gastrointestinal tract, liver and spleen. No lethality, macroscopic, tissue or haematological changes were recorded two weeks post exposure, indicating reversible toxic effects. LC-MS/MS analysis of the main organs showed a dose-dependency in gastrointestinal absorption of these toxins: at 24h, the highest levels were detected in the stomach and, in descending order, in the intestinal content, liver, small intestine, kidneys, lungs, large intestine, heart as well as detectable traces in the brain. After 14days, AZA1 and AZA2 were still detectable in almost all the organs and intestinal content., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The regions of Durham and York in Ontario, Canada have partnered to construct an energy-from-waste thermal treatment facility as part of a long term strategy for the management of their municipal solid waste. This paper presents the results of a comprehensive human health risk assessment for this facility. This assessment was based on extensive sampling of baseline environmental conditions (e.g., collection and analysis of air, soil, water, and biota samples) as well as detailed site specific modeling to predict facility-related emissions of 87 identified contaminants of potential concern. Emissions were estimated for both the approved initial operating design capacity of the facility (140,000 tonnes per year) and for the maximum design capacity (400,000 tonnes per year). For the 140,000 tonnes per year scenario, this assessment indicated that facility-related emissions are unlikely to cause adverse health risks to local residents, farmers, or other receptors (e.g., recreational users). For the 400,000 tonnes per year scenarios, slightly elevated risks were noted with respect to inhalation (hydrogen chloride) and infant consumption of breast milk (dioxins and furans), but only during predicted 'upset conditions' (i.e. facility start-up, shutdown, and loss of air pollution control) that represent unusual and/or transient occurrences. However, current provincial regulations require that additional environmental screening would be mandatory prior to expansion of the facility beyond the initial approved capacity (140,000 tonnes per year). Therefore, the potential risks due to upset conditions for the 400,000 tonnes per year scenario should be more closely investigated if future expansion is pursued., (© 2013.)

Must molecular mechanisms be the same for concentration addition to predict the effect of a mixture or is it sufficient for compounds to affect similar pathways or common outcomes? Does concentration addition provide a closer approximation to observations than alternative models such as independent action? Suppose effects are mediated by hormone A through receptor R, synthesis of A is reduced by compound B, and that C is a competitive antagonist to A. Both B and C reduce levels of the receptor-ligand complex AR but via different specific mechanisms. Are combinations of B and C concentration additive? We used simple pharmacodynamic models, deriving mathematical models using equilibrium binding and mass balance. Assume A binds the receptor at one site of R with effects proportional to the concentration of AR. Let C act as a competitive antagonist via the Gaddum equation. Let B affect synthesis of A via a function g(B). We derive a model describing the joint response surface of B and C, and a function describing its isoboles. Under concentration addition, the isoboles must be negatively sloped straight lines. We show that linearity of the isoboles depends crucially on g(B). The mixture is concentration additive if g″(B), the second derivative of g(B) with respect to B, is always zero. Responses are greater than concentration additive if g″(B) is always positive and less than concentration additive if g″(B) is always negative. We describe functions g(B) that lead to all three cases as well as one that is greater than concentration additive in some regions and less than concentration additive in others. At least in this simple model, concentration addition cannot be assumed: mixtures of competitive antagonists and compounds that alter hormone synthesis can lead to results that are concentration additive, greater than concentration additive or less than concentration additive. Nevertheless, concentration addition appears to provide a closer approximation to the pharmacodynamic model examined here than independent action. Care needs to be taken in extrapolating to other situations, but analysis of simple pharmacodynamic models appears to be a useful strategy., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

EPA recommends sensitivity analyses when applying the toxic equivalency factor (TEF) method to evaluate exposures to dioxin-like compounds (DLCs). Applying the World Health Organization's (WHO) 2005 TEF values and estimating average U.S. daily dietary intakes of 25 DLCs from eight food categories, we estimate a toxic equivalency (TEQ) intake of 23 pg/day. Among DLCs, PCB 126 (26%) and 1,2,3,7,8-PeCDD (23%) dominate TEQ intakes. Among food categories, milk (14%), other dairy (28%), beef (25%), and seafood (18%) most influenced TEQ intakes. We develop two approaches to estimate alternative TEF values. Based on WHO's assumption regarding TEF uncertainty, Approach1 estimates upper and lower TEFs for each DLC by multiplying and dividing, respectively, its individual TEF by ± half a log. Based on compiled empirical ranges of relative potency estimates, Approach2 uses percentile values for individual TEFs. Total TEQ intake estimates using the lower and upper TEFs based on Approach1 were 8 and 68 pg TEQ/day, respectively. The 25th and 75th percentile TEFs from Approach2 yielded 12 and 28 pg TEQ/day, respectively. The influential DLCs and food categories remained consistent across alternative TEFs, except at the 90th percentile using Approach2. We highlight the need for developing underlying TEF probability distributions., (Published by Elsevier Inc.)

Dioxins are a family of persistent organic pollutants (POPs) listed under the Stockholm Convention, and include PCDDs, PCDFs, and dioxin-like PCBs. These toxic chemicals are carcinogenic, widely dispersed, and have long half-lives. They have contaminated the food web and, being fat-soluble, accumulate in adipose tissues and milk in the human body. To assess human exposure, we collected breast milk samples from 137 first-time mothers recruited from around Hong Kong. Samples were analysed by HRGC-HRMS in four pools, according to the subject's age and length of residency. Exposure was related to age, duration of stay, and possibly diet. Generally, older mothers, and mothers with a longer stay in Hong Kong, had higher levels of dioxins in their milk. This pattern was clearest for the PCBs, although deviations were observed for some of the PCDD/Fs. Mean concentrations, measured per gram of lipid weight in terms of WHO toxic equivalents (WHO-TEQs), were 7.48 pg/g for PCDD/Fs and 3.79 pg/g for PCBs, giving a total of 11.27 pg/g for PCDD/Fs and PCBs combined. Compared to an earlier Hong Kong study we conducted in 2002, the mean WHO-TEQ values in our latest findings were about 9% lower overall for PCDD/Fs and 19% lower for PCBs, with the mean total WHO-TEQ for PCDD/Fs and PCBs being around 13% lower in this study. This indicates a general declining trend in the levels of POPs in Hong Kong. However, our levels were still high when compared to those in some other Asian-Pacific countries. More stringent policies on reducing and eliminating POPs should help to lower these. Continued surveillance for POPs in human milk, as well as in common foodstuffs, will provide us with important information on human exposures that will be necessary for tracking our progress, and making future health risk assessments., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Endocrine-disrupting chemicals currently represent one of the major concerns and this study was aimed to investigate the effects of different doses of cadmium, widespread toxic metal, on the levels of thyroid hormones and to calculate Benchmark doses for these effects. Furthermore, the effects of co-exposure to cadmium and polychlorinated biphenyls on thyroid function were investigated. Six orally-treated groups of rats were receiving 0.3, 0.6, 1.25, 2.5, 5 and 10mgCd/kgb.w./day, five groups were orally treated with 0.5, 1, 2, 4 and 8mgPCBs/kgb.w./day, while nine groups of rats were orally-treated with different dose combinations of Cd and PCBs (0.6, 1.25 and 2.5mgCd/kgb.w. and 2, 4 and 8mgPCBs/kgb.w./day), during 28 days. Thyroid hormones were adversely affected by cadmium, with most prominent effect observed on triiodothyroxine levels indicating Cd interference with thyroid function at extrathyroidal level. Calculated Benchmark doses for Cd effects on thyroid hormones indicate triiodothyroxine as the most sensitive one that can be used as a basis for risk assessment. This study also implicates possible synergistic effects of Cd and PCBs on thyroid function as a consequence of their interference at different levels of thyroid homeostasis., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)