81 research outputs found
Application of sand and geotextile envelope in subsurface drip irrigation
Subsurface drip irrigation is a technology used for better management of irrigation water. This technique is more desirable in arid and semi-arid region, because of decreasing soil surface evaporation and more efficiency of irrigation system in comparison with the other irrigation systems. Inaddition, this system is a safer way for treated wastewater (TWW) reuse in irrigation lands. But roots and clay particles can clog drip emitters in systems buried below the soil surface. In this paper, sand and geotextile filtration methods have been suggested for solving root intrusion and biological plugging problems for subsurface drip applications. Sand envelope around the emitters has been recommended for deeper root zone and long term application of system, while geotextile envelope is suitable for seasonal crops with shallow root.Key words: Subsurface drip irrigation, sand and geotextile, emitters
Management ofwater content of soil in cultivation of greenhouse cucumber (Cucumis sativus L, Nasim variety) in Isfahan- Iran
Measurement and control of water content of soil is an essential factor in irrigation management, to apply the best management practice for reducing water consumption and improving product quality. The water content of soil is an important factor in greenhouse where it is directly related to the total amount of water consumed for irrigation. Since cucumbers (Cucumis sativus L, Nasim variety) is considered as the main and much used summer crop in Iran, which are extremely sensitive to adverse conditions particularly water stress, determination and supply of water is vital for this plant. To this end, maximum allowable depletion (MAD) should be determined. This experiment was conducted in the research greenhouse (Plastic Covered) of Islamic Azad University in Khorasgan, Isfahan, during a period of five months. This project was implemented in the framework of three 40, 60, and 80 cm bar water suction treatments with three replications using tensiometer. Before treatment application, water content of soil was determined in weight. MAD in 40, 60, and 80 cm bar treatments was 22, 32 and 50%, respectively. Statistical results and mean comparison demonstrated that MAD of 22 and 32% led to a significant yield increase (P<0.001), while MAD of 50% had the least yield. The results reveal that there was a significant difference between MAD of 22 and 32% in increasing leaf area index (LAI) (P<0.001).Key words: Maximum allowable depletion, greenhouse cucumber, tensiometer, leaf area index
Application of dirichlet process and support vector machine techniques for mapping alteration zones associated with porphyry copper deposit using aster remote sensing imagery
The application of machine learning (ML) algorithms for processing remote sensing data is momentous, particularly for mapping hydrothermal alteration zones associated with porphyry copper deposits. The unsupervised Dirichlet Process (DP) and the supervised Support Vector Machine (SVM) techniques can be executed for mapping hydrothermal alteration zones associated with porphyry copper deposits. The main objective of this investigation is to practice an algorithm that can accurately model the best training data as input for supervised methods such as SVM. For this purpose, the Zefreh porphyry copper deposit located in the Urumieh-Dokhtar Magmatic Arc (UDMA) of central Iran was selected and used as training data. Initially, using ASTER data, different alteration zones of the Zefreh porphyry copper deposit were detected by Band Ratio, Relative Band Depth (RBD), Linear Spectral Unmixing (LSU), Spectral Feature Fitting (SFF), and Orthogonal Subspace Projection (OSP) techniques. Then, using the DP method, the exact extent of each alteration was determined. Finally, the detected alterations were used as training data to identify similar alteration zones in full scene of ASTER using SVM and Spectral Angle Mapper (SAM) methods. Several high potential zones were identified in the study area. Field surveys and laboratory analysis were used to validate the image processing results. This investigation demonstrates that the application of the SVM algorithm for mapping hydrothermal alteration zones associated with porphyry copper deposits is broadly applicable to ASTER data and can be used for prospectivity mapping in many metallogenic provinces around the world
Sex Differential Genetic Effect of Chromosome 9p21 on Subclinical Atherosclerosis
BACKGROUND: Chromosome 9p21 has recently been shown to be a risk region for a broad range of vascular diseases. Since carotid intima-media thickness (IMT) and plaque are independent predictors for vascular diseases, the association between 9p21 and these two phenotypes was investigated. METHODOLOGY/PRINCIPAL FINDINGS: Carotid segment-specific IMT and plaques were obtained in 1083 stroke- and myocardial infarction-free volunteers. We tested the genotypes and haplotypes of key single nucleotide polymorphisms (SNPs) on chromosome 9p21 for the associations with carotid IMT and plaque. Multivariate permutation analyses demonstrated that carriers of the T allele of SNP rs1333040 were significantly associated with thicker common carotid artery (CCA) IMT (p=0.021) and internal carotid artery (ICA) IMT (p=0.033). The risk G allele of SNP rs2383207 was associated with ICA IMT (p=0.007). Carriers of the C allele of SNP rs1333049 were found to be significantly associated with thicker ICA IMT (p=0.010) and the greater risk for the presence of carotid plaque (OR=1.57 for heterozygous carriers; OR=1.75 for homozygous carriers). Haplotype analysis showed a global p value of 0.031 for ICA IMT and 0.115 for the presence of carotid plaque. Comparing with the other haplotypes, the risk TGC haplotype yielded an adjusted p value of 0.011 and 0.017 for thicker ICA IMT and the presence of carotid plaque respectively. Further analyzing the data separated by sex, the results were significant only in men but not in women. CONCLUSIONS: Chromosome 9p21 had a significant association with carotid atherosclerosis, especially ICA IMT. Furthermore, such genetic effect was in a gender-specific manner in the Han Chinese population
The 2021 report of the Lancet Countdown on health and climate change: code red for a healthy future
A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)
Meeting abstrac
The value of the apoB/apoAΙ ratio and the non-HDL-C/HDL-C ratio in predicting carotid atherosclerosis among Chinese individuals with metabolic syndrome: a cross-sectional study
Effect of Boswellia serrata Resin Supplementation on Basic Chemical and Mineral Element Composition in the Muscles and Liver of Broiler Chickens
Describing knowledge encounters in healthcare: a mixed studies systematic review and development of a classification
This review was self-funded
A systematic review and meta-analysis on Staphylococcus aureus carriage in psoriasis, acne and rosacea
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