34 research outputs found
Associative effects of activated carbon biochar and arbuscular mycorrhizal fungi on wheat for reducing nickel food chain bioavailability
Heavy metal stress and less nutrient availability are some of the major concerns in agriculture. Both abiotic stresses have potential to decrease the crops productivity. On the other hand, organic fertilizers i.e., activated carbon biochar (ACB) and arbuscular mycorrhizal fungi (AMF) increase nutritional and heavy metal like Nickel (Ni) stress tolerance and provide immunity to plants for their survival in unfavorable environments. Previous studies have only looked at single applications of either ACB or AMF thus far. There is limited evidence of their synergistic effects, especially in plants growing in soil contaminated with nickel (Ni). To cover the knowledge gap of combined use of AMF inoculation (Glomus intraradices) and/or wheat straw biochar amendments on wheat growth, antioxidant activities and osmolytes concentration, present study is conducted. The use of either the AMF inoculant or the ACB alone resulted in improved wheat growth and decreased Ni uptake. Furthermore, sole AMF or ACB also reduced Ni stress effectively, allowing wheat to grow faster and reducing soil Ni transfer into plant tissue. In comparison to a control, adding ACB with AMF inoculant considerably increased fungal populations. The most significant increase in wheat growth and decrease in tissue Ni contents came from amending soil with AMF inoculant and biochar. Inducing soil alkalinization and causing Ni immobilization, as well as decreasing Ni phyto-availability, the combination treatment had a synergistic impact. These findings imply that AMF inoculation in ACB treatment could be used not only for wheat production but also for Ni-contaminated soil phyto-stabilization. (C) 2022 The Author(s). Published by Elsevier B.V.Peer reviewe
Forecasting Tunisian type 2 diabetes prevalence to 2027: validation of a simple model.
BACKGROUND: Most projections of type 2 diabetes (T2D) prevalence are simply based on demographic change (i.e. ageing). We developed a model to predict future trends in T2D prevalence in Tunisia, explicitly taking into account trends in major risk factors (obesity and smoking). This could improve assessment of policy options for prevention and health service planning. METHODS: The IMPACT T2D model uses a Markov approach to integrate population, obesity and smoking trends to estimate future T2D prevalence. We developed a model for the Tunisian population from 1997 to 2027, and validated the model outputs by comparing with a subsequent T2D prevalence survey conducted in 2005. RESULTS: The model estimated that the prevalence of T2D among Tunisians aged over 25 years was 12.0% in 1997 (95% confidence intervals 9.6%-14.4%), increasing to 15.1% (12.5%-17.4%) in 2005. Between 1997 and 2005, observed prevalence in men increased from 13.5% to 16.1% and in women from 12.9% to 14.1%. The model forecast for a dramatic rise in prevalence by 2027 (26.6% overall, 28.6% in men and 24.7% in women). However, if obesity prevalence declined by 20% in the 10 years from 2013, and if smoking decreased by 20% over 10 years from 2009, a 3.3% reduction in T2D prevalence could be achieved in 2027 (2.5% in men and 4.1% in women). CONCLUSIONS: This innovative model provides a reasonably close estimate of T2D prevalence for Tunisia over the 1997-2027 period. Diabetes burden is now a significant public health challenge. Our model predicts that this burden will increase significantly in the next two decades. Tackling obesity, smoking and other T2D risk factors thus needs urgent action. Tunisian decision makers have therefore defined two strategies: obesity reduction and tobacco control. Responses will be evaluated in future population surveys
Empirical Analysis for Stock Price Prediction Using NARX Model with Exogenous Technical Indicators
The file attached to this record is the Publisher's final version. Open access article.Stock price prediction is one of the major challenges for investors who participate in the stock markets. Therefore, different
methods have been explored by practitioners and academicians to predict stock price movement. Artificial intelligence models are
one of the methods that attracted many researchers in the field of financial prediction in the stock market. This study investigates
the prediction of the daily stock prices for Commerce International Merchant Bankers (CIMB) using technical indicators in a
NARX neural network model. The methodology employs comprehensive parameter trails for different combinations of input
variables and different neural network designs. The study seeks to investigate the optimal artificial neural networks (ANN)
parameters and settings that enhance the performance of the NARX model. Therefore, extensive parameter trails were studied for
various combinations of input variables and NARX neural network configurations. The proposed model is further enhanced by
preprocessing and optimising the NARX model’s input and output parameters. The prediction performance is assessed based on
the mean squared error (MSE), R-squared, and hit rate. The performance of the proposed model is compared with other models,
and it is shown that the utilisation of technical indicators with the NARX neural network improves the accuracy of one-step-ahead
prediction for CIMB stock in Malaysia. The performance of the proposed model is further improved by optimising the input data
and neural network parameters. The improved prediction of stock prices could help investors increase their returns from investment in stock markets
Prediction Models Based on Soil Characteristics for Evaluation of the Accumulation Capacity of Nine Metals by Forage Sorghum Grown in Agricultural Soils Treated with Varying Amounts of Poultry Manure
Predictive models were generated to evaluate the degree to which nine metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) were absorbed by the leaves, stems and roots of forage sorghum in growing media comprising soil admixed with poultry manure concentrations of 0, 10, 20, 30 and 40 g/kg. The data revealed that the greatest contents of the majority of the metals were evident in the roots rather than in the stems and leaves. A bioaccumulation factor (BAF) 1. Translocation factor values were < 1 for all metals with the exception of Co, Cr and Ni, which displayed values of 1.20, 1.67 and 1.35 for the leaves, and 1.12, 1.23 and 1.24, respectively, for the stems. The soil pH had a negative association with metal tissues in plant parts. A positive relationship was observed with respect to plant metal contents, electrical conductivity and organic matter quantity. The designed models exhibited a high standard of data precision; any variations between the predicted and experimentally observed contents for the nine metals in the three plant tissue components were nonsignificant. Thus, it was concluded that the presented predictive models constitute a pragmatic tool to establish the safety from risk to human well-being with respect to growing forage sorghum when cultivating media fortified with poultry manure.The authors extend their appreciation to the Deputyship for Research and Innovation, Ministry of Education in Saudi Arabia for funding this research work through the project number IFP-KKU-2020/3.Peer reviewe
Transcriptional analysis of Rhazya stricta in response to jasmonic acid
Background: Jasmonic acid (JA) is a signal transducer molecule that plays an important role in plant development and stress response; it can also efficiently stimulate secondary metabolism in plant cells. Results: RNA-Seq technology was applied to identify differentially expressed genes and study the time course of gene expression in Rhazya stricta in response to JA. Of more than 288 million total reads, approximately 27% were mapped to genes in the reference genome. Genes involved during the secondary metabolite pathways were up- or downregulated when treated with JA in R. stricta. Functional annotation and pathway analysis of all up- and downregulated genes identified many biological processes and molecular functions. Jasmonic acid biosynthetic, cell wall organization, and chlorophyll metabolic processes were upregulated at days 2, 6, and 12, respectively. Similarly, the molecular functions of calcium-transporting ATPase activity, ADP binding, and protein kinase activity were also upregulated at days 2, 6, and 12, respectively. Time-dependent transcriptional gene expression analysis showed that JA can induce signaling in the phenylpropanoid and aromatic acid pathways. These pathways are responsible for the production of secondary metabolites, which are essential for the development and environmental defense mechanism of R. stricta during stress conditions. Conclusions: Our results suggested that genes involved in flavonoid biosynthesis and aromatic acid synthesis pathways were upregulated during JA stress. However, monoterpenoid indole alkaloid (MIA) was unaffected by JA treatment. Hence, we can postulate that JA plays an important role in R. stricta during plant development and environmental stress conditions. How to cite: Hajrah, NH, Rabah SO, Alghamdi MK, et al. Transcriptional analysis of Rhazya stricta in response to jasmonic acid. Electron J Biotechnol 2021;50. https://doi.org/10.1016/j.ejbt.2021.01.00
THERMAL LOSSES REDUCTION FOR A TROUGH SOLAR COLLECTOR: PART 1 FLUID FLOW
The flow of the wind near an absorber of a trough collector is analyzed. Since this absorber loss useful heat into the ambient, it is necessary to reduce that heat. The common strategy of reduction is the use of a vacuum tube. The maintaining of vacuum is difficult due to air leak or glass fracture led to find another replacement for this strategy. The idea of the present work is to put a half circular disc in front of the receiver in order to reduce the air velocity near the tube and reduce the heat transfer process. The flow is analyzed in the area to find the streamlines of flow and the behavior of air for a different air velocities and trough orientations. The analysis is done by using COMSOL Multiphysics program V4.4. The data show that the overall air velocity is reduced near the receiver as predicted
FIGURES 7−14. Paraorosius minuicus, 7 in Paraorosius, a new genus of leafhopper (Hemiptera: Cicadellidae: Deltocephalinae: Opsiini), with description of a new species from the Middle East
FIGURES 7−14. Paraorosius minuicus, 7, Aedeagus dorsal view, 8, Lateral view; 9, Connective; 10, Style; 11, Pygofer; 12, Subgenital plate; 13, valve; 14, ♀7th sternite
Integrated Pest Management ( IPM ) for Date Palm in the Kingdom of Saudi Arabia
The aim of this study is to evaluate the most important damaging diseases and pests of the date palm ( Phoenix dactylifera L. ) in the Kingdom of Saudi Arabia as cited in the publications and reports.
The results of this study indicated that the red palm weevil, which was reported in the country for the first time twelve years ago, is the most serious insects pest. This is in addition to the other arthropod pests which include : Oryctes elegans, Pseudophilus testaceous, Batrachedra amydraula, Arenipses sabella, Chrysomphalus dictypermi, Ommatissus binotatus, Parlatoria blanchardi, Oligonychus afrasiaticus, and birds which attack the fruits. The date palm diseases caused by fungi are of great economic importance. The wilt diseases, Khamedj, Al-wijam, and Diplodia diseases are among the important diseases of date palm in some growing areas of the Kingdom.
The study suggests the adoption of a comprehensive IPM program that suits the infection of date palm by one or more of the previous pests. This program includes : cultural practices ( such as selection of healthy off-shoots, resistant to pests and free of diseases ) and other cultural practices, physical, mechanical, legestilative, biological, chemical and other control methods that my influence pest behavior and minimize damage that can be caused by these serious pests
Potential of resistance inducers for citrus huanglongbing management via soil application and assessment of induction of pathogenesis-related protein genes
Huanglongbing (HLB) or citrus greening currently is the most devastating citrus disease worldwide. Unfortunately, no practical cure has been available up to now. This makes the control of HLB as early as possible very important to be conducted. The objective of this study was to investigate the efficacy of the application of salicylic acid (SA) and Phenylacetic acid (PAA) on one-year-old seedlings of different citrus species (Citrus reticulata, C. sinensis, C. aurantifolii) growing on C. volkameriana and C. aurantium by soil drench methods. Factorial analysis of variance showed the percent change in “Candidatus Liberibacter asiaticus” titer and disease severity on a different combination of citrus species growing on the two rootstocks treated with inducers and Oxytetracycline (OTC) were significantly different compared to the untreated plants. SA alone or in combination with OTC provided excellent (P-value < 0.05) control of HLB based on all parameters. The interaction between both factors (Rootstocks x Citrus species) significantly influenced the Ct value (P-value = 0.0001). “Candidatus Liberibacter asiaticus” titer in plants treated with OTC was reduced significantly with a range of −18.75 up to −78.42. Overall, the highest reduction was observed in the application of OTC on sweet orange growing on C. volkameriana (−78.42), while the lowest reduction was observed in the same cultivar which was treated with a combination of SA and OTC (−3.36). Induction of pathogenesis-related (PR) genes, i.e., PR1, PR2, and PR15, biosynthesis of Jasmonic acid and ethylene which are also important pathways to defense activity were also significantly increased in treated plants compared to untreated plants. This study suggests that the application of inducer alone is acceptable for HLB management. We proposed the application of SA and PAA as a soil drench on the citrus seedlings as promising, easy, and environmentally safe for HLB disease control on citrus seedlings
Differentiation of ‘Candidatus Liberibacter asiaticus’ in Saudi Arabia based on tandem repeat variability in genomic locus
Citrus greening, or huanglongbing, is a destructive disease threatening many citrus worldwide, and drastically altering the global dynamics of the citrus industry. The disease is caused by one of several unculturable bacterial species belonging to ‘Candidatus Liberibacter’. The recent availability of complete genome sequences of ‘Candidatus Liberibacter asiaticus’ (CLas) has facilitated comprehensive assessments of genomic variability using a range of approaches, including short tandem repeat analysis. The objective of this study was to evaluate the genetic diversity of CLas populations in Saudi Arabia based on tandem repeat number (TRN) within the CLIBASIA_01645 locus, predicted to encode the bacteriophage C1 repressor protein. Results indicated that the genotype richness of the Saudi Arabian CLas isolates was conserved by 27% based on the TRN locus. Four different genotypes TRN2, TRN3, TRN4, and TRN5 were identified. However, the TRN2 and TRN5 were the most dominant genotypes. All four of the TRN genotypes were associated with CLas-positive mandarin (Citrus reticulata) or sweet orange (C. sinensis) citrus trees. The diversity (H = 0.69) and evenness (H'=0.914) were overall relatively high, with the northern region of Saudi Arabia harboring the highest diversity (0.7) and evenness score (0.9–1.0). Phylogenetic analysis of the CLas-bacteriophage C1 repressor protein of the Saudi Arabian isolates indicated CLas was more closely related to ‘Candidatus Liberibacter africanus’ than to ‘Candidatus Liberibacter americanus’