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Background and objective: Compounds having imine or azomethine (–C=N–) functional group are known as Schiff bases. Schiff bases compounds are found to be an active pharmacophore for the design and development of various bioactive lead compounds. In this study, several new Schiff base compounds have been synthesized and characterized. Methods: Williamson ether synthesis process has been used to synthesize -alkyloxy and substituted benzyloxy of benzaldehyde. Differently substituted ether benzaldehydes used to react with 4-amino-1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one in one hand and 1H-benzo[d]imidazol-2-amine on the other hand to produce Schiff base compounds. Results: Synthesized ether derivative compounds (3a-e) were converted to new series of Schiff bases (4a-e and 5a-e) by condensation of equal molar amounts of compounds (3a-e) with different heterocyclic amines dissolved in absolute ethanol. All synthesized compounds were confirmed by (IR, 1H-NMR, and 13CNMR) spectroscopy. All synthesized compounds were evaluated for antibacterial activities in vitro against Gram-positive and Gram-negative bacteria. Conclusion: All compounds were purely synthesized, and all compounds were indicated growth inhibition against Escherichia coli, and Staphylococcus aureus, respectively with different inhibition zones staring from 13 to 33 mm.

The 2017–2027 National Academies' Decadal Survey, Thriving on Our Changing Planet, recommended Surface Biology and Geology (SBG) as a “Designated Targeted Observable” (DO). The SBG DO is based on the need for capabilities to acquire global, high spatial resolution, visible to shortwave infrared (VSWIR; 380–2500 nm; ~30 m pixel resolution) hyperspectral (imaging spectroscopy) and multispectral midwave and thermal infrared (MWIR: 3–5 μm; TIR: 8–12 μm; ~60 m pixel resolution) measurements with sub-monthly temporal revisits over terrestrial, freshwater, and coastal marine habitats. To address the various mission design needs, an SBG Algorithms Working Group of multidisciplinary researchers has been formed to review and evaluate the algorithms applicable to the SBG DO across a wide range of Earth science disciplines, including terrestrial and aquatic ecology, atmospheric science, geology, and hydrology. Here, we summarize current state-of-the-practice VSWIR and TIR algorithms that use airborne or orbital spectral imaging observations to address the SBG DO priorities identified by the Decadal Survey: (i) terrestrial vegetation physiology, functional traits, and health; (ii) inland and coastal aquatic ecosystems physiology, functional traits, and health; (iii) snow and ice accumulation, melting, and albedo; (iv) active surface composition (eruptions, landslides, evolving landscapes, hazard risks); (v) effects of changing land use on surface energy, water, momentum, and carbon fluxes; and (vi) managing agriculture, natural habitats, water use/quality, and urban development. We review existing algorithms in the following categories: snow/ice, aquatic environments, geology, and terrestrial vegetation, and summarize the community-state-of-practice in each category. This effort synthesizes the findings of more than 130 scientists.

The sparse canopy cover and large contribution of bright background soil, along with the heterogeneous vegetation types in close proximity, are common challenges for mapping dryland vegetation with remote sensing. Consequently, the results of a single classification algorithm or one type of sensor to characterize dryland vegetation typically show low accuracy and lack robustness. In our study, we improved classification accuracy in a semi-arid ecosystem based on the use of vegetation optical (hyperspectral) and structural (lidar) information combined with the environmental characteristics of the landscape. To accomplish this goal, we used both spectral angle mapper (SAM) and multiple endmember spectral mixture analysis (MESMA) for optical vegetation classification. Lidar-derived maximum vegetation height and delineated riparian zones were then used to modify the optical classification. Incorporating the lidar information into the classification scheme increased the overall accuracy from 60% to 89%. Canopy structure can have a strong influence on spectral variability and the lidar provided complementary information for SAM's sensitivity to shape but not magnitude of the spectra. Similar approaches to map large regions of drylands with low uncertainty may be readily implemented with unmixing algorithms applied to upcoming space-based imaging spectroscopy and lidar. This study advances our understanding of the nuances associated with mapping xeric and mesic regions, and highlights the importance of incorporating complementary algorithms and sensors to accurately characterize the heterogeneity of dryland ecosystems.

In this article, an active electrically small Horn antenna for very high frequency (VHF) and ultra-high frequency (UHF) frequencies is presented. The proposed horn antenna has a height of 5 cm and a diameter of 4.28 cm which can cover 6-12 GHz without a special active circuit with the VSWR of less than 2. A Non-foster Active Adaptation Circuit is used to reduce the antenna input frequency from 164 MHz to 880 MHz. Good matching is visible between the simulation results and the measurement of the antenna reflection coefficient with the active matching circuit. The proposed structure has more than 137 % bandwidth. With the proposed active antenna, the problem of non-portability of VHF and UHF Horn antenna antennas has been solved. Finally, by analyzing the time domain, the stability of the circuit is examined, and the results of the stability test show that the system, including the antenna and the circuit, is stable. The antenna and the matching circuits are simulated by CST microwave studio and advanced design system, respectively. [ABSTRACT FROM AUTHOR]

Enzymes play a crucial role in plant-pathogen interactions and are very important to manage plant diseases. Take-all is a disease (Gaeumannomyces graminis var. tritici) affecting the crowns and roots in wheat. So far, the resistance mechanism of this disease has not been identified; therefore, this research was performed to identify the components of resistance to this disease in a number of wheat genotypes. In this study, 8 bread wheat genotypes were cultured, and the changes in “peroxidase, Polyphenol Oxidase (PPO), Phenylalanine Ammonia-Lyase (PAL), and total protein” was assessed in 0, 4, 7, 9, and 12 days after inoculation. The results showed that different genotypes of wheat had different pathogenicity reactions to the take-all disease. Based on the average disease intensity, the genotypes were divided into three groups: resistant, moderately resistant, and susceptible. The results indicated that the level of polyphenol oxidase and phenylalanine ammonialyase, and the total protein increased in the resistant and moderately resistant groups. Cluster analysis by K-means was performed to produce three clusters. Polyphenol oxidase activity, phenylalanine ammonia-lyase activity, and total protein content in the second (resistant) and third (moderately resistant) clusters were higher than the first cluster (susceptible). Multivariate analysis indicated that peroxidase enzyme might indirectly influence the resistance. The results have clarified the role of polyphenol oxidase enzymes and total protein in enhancing resistance to take-all disease. [ABSTRACT FROM AUTHOR]

People generally seek a better life, so most of them migrate to countries and places that help them improve their standard of living or escape from political turmoil and wars. Still, migration may constitute a set of effects on migrants and the countries to which they go. Migration affects some individuals by making it difficult for them to adapt to the nature of life in the new region, especially with the emergence of cultural and social differences, and also many immigrants do not find anything but difficult jobs that take long working hours and low wages complex migration affects countries with high population density, which leads to an increase in the unemployment rate poverty and the emergence of many political and economic consequence. This study seeks many factors and reasons that lead to immigration from the southern and capital of Iraq to Erbil city. The researchers built his information by ddistributing200 questioner and obtained 186 Usable with ignoring 14 nonusable. The result observed that there is no significant correlation between the independent variable (internal migration) and the dependent variable (economic geography), depending on the value of the statistical significance (0.05), whose value was more significant than the level of significance (0.05), and this indicates that internal migration has nothing to do with the changes taking place in economic geography.

Root and crown rot of wheat is caused by the fungus Gaeumannomyces graminis var. tritici. "Take-all" is an important disease affecting wheat, and its incidence has been reported in several provinces of Iran. To identify resistant cultivars, bread wheat germplasm should be evaluated. To evaluate bread wheat germplasm in response to Iranian isolate fungus (T-41) of Gaeumannomyces graminis var. tritici, 333 genotype of bread wheat, collected from different locations of Iran and other countries were evaluated to take-all in greenhouse conditions. Two experiments were conducted, the first with 89 and the second with 244 genotypes. The measured traits were amount of root and crown infection, disease intensity, wet and dry biomass, and height of shoots. Analysis of variance and means comparison for the parameters indicated that in the first experiment, two genotypes were resistant to the disease, and the rates of disease intensity in these genotypes were 0.13 and 0.06. In the second experiment, five completely resistant genotypes were identified with disease intensity ratings of '0'. The identified resistant genotypes screened from both experiments were re-evaluated, and the results were the same. Mean comparison between winter and spring types for dry weight and disease intensity showed that winter wheat is more resistant than spring type. The results of this research showed that there is resistance resource to take-all (T-41 isolate), in this germplasm. Since the experiment was conducted in greenhouse conditions, these genotypes should be tested against this disease in infected conditions at field. [ABSTRACT FROM AUTHOR]