51 research outputs found

    MONITORING AND FORECASTING LAND USE CHANGES AND URBAN GROWTH USING MARKOVIAN CELLULAR AUTOMATA SPATIAL MODEL – CASE STUDY: MARSA MATROUH CITY, EGYPT

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    The objective of this paper is to establish a framework that quantifies land use changes and forecasts urban growth trends. Satellite imageries with moderate resolution (Landsat TM 5 and 7) are used to study the changes in land cover and land uses over a 15 years period (1987 to 2002). Two land use/land cover maps are produced for the two dates, then processed using a two steps Markovian Cellular Automata model. To enhance the projected land use of 2006, socioeconomic preferences and anthropogenic factors are collected and mapped using a raster/vector hybrid geographic information system. The anthropogenic factors are identified and weighted by a selected group of stakeholders. Finally, these factors are mapped and presented in raster form. The final projection of land use and urban growth is assessed both spatially and quantitatively. The spatial assessment is achieved by comparing the projection land use for 2006 against a spatial high resolution image (IKONOS MS) of the same area and date. Quantitative assessment of the model is achieved by creating an error matrix that compares the results of the projected land use to the actual land use depicted in the high resolution image. The accuracy assessment demonstrated an accuracy of 69.5%, which is considered acceptable in the modeling of land use changes using Landsat imageries

    A Survey of Satellite Biological Sensor Application for Terrestrial and Aquatic Ecosystems

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    The state of the ecosystems can be inferred in two ways, known as bioinference. One way (ground-based) is the use of some organisms to determine the environmental conditions within an ecosystem. The other is the use of multiband airborne or satellite imagery to identify the vegetation cover status, and also to track the biological diversity in marine ecosystems such as coral reef status, resources variation, and pollution. The standard example for the first state is the plankton as they represent a primary tool for ecologists to assess the health state of the marine environment. Their fast responses to the variability of the ecosystem, their nonexploitation as commercial organisms, and their favoring of subtle environmental conditions have suggested them to be bioindicators of climate variability. These organisms can be used to identify many environmental problems including water acidification, eutrophication, and pollution. Remote sensing technique is being widely used today to solve many environmental problems due to the broad view and accuracy of the results and its participation in determining the environmental conditions of different ecosystems. For example, remote sensing applications are used in vegetation and mangrove ecosystem management. Moreover, it is used to assess eutrophication problems by multiband spectrum remote sensing

    Analyzing Black Cloud Dynamics over Cairo, Nile Delta Region and Alexandria using Aerosols and Water Vapor Data

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    Cairo is the largest city of Africa and one of the world’s megacities, with a population of more than 20 million people and containing more than one third of the national industry. It is a rapidly expanding city which leads to many associated environmental problems. As a result, it is also one of the most air polluted megacities in the world (Molina and Molina, 2004). It suffers from high ambient concentrations of atmospheric pollutants including particulates (PM), carbon monoxide, nitrogen oxides, ozone and sulfur dioxide (Abu-Allaban et al., 2007, Abu-Allaban et al., 2002, El-Metwally et al., 2008). The pollution phenomenon locally known as “Black cloud” over Cairo has been attributed to many reasons among which are biomass burning, local emission and long range transport during the fall season.Several studies have been conducted to address and discuss the forth mentioned reasons for the increased pollution levels over Cairo and the greater Delta region using ground-based and satellite air quality data as compared to other megacities.https://digitalcommons.chapman.edu/sees_books/1000/thumbnail.jp

    Aerosol Climatology Over Nile Delta Based on MODIS, MISR and OMI Satellite Data

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    Since 1999 Cairo and the Nile delta region have suffered from air pollution episodes called the “black cloud” during the fall season. These have been attributed to either burning of agriculture waste or long-range transport of desert dust. Here we present a detailed analysis of the optical and microphysical aerosol properties, based on satellite data. Monthly mean values of Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol optical depth (AOD) at 550 nm were examined for the 10 yr period from 2000–2009. Significant monthly variability is observed in the AOD with maxima in April or May (_0.5) and October (_0.45), and a minimum in December and January (_0.2). Monthly mean values of UV Aerosol Index (UVAI) retrieved by the Ozone Monitoring Instrument (OMI) for 4 yr (2005–2008) exhibit the same AOD pattern. The carbonaceous aerosols during the black cloud periods are confined to the planetary boundary layer (PBL), while dust aerosols exist over a wider range of altitudes, as shown by Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) aerosol profiles. The monthly climatology of Multi-angle Imaging Spectro-Radiometer (MISR) data show that the aerosols during the black cloud periods are spherical with a higher percentage of small and medium size particles, whereas the spring aerosols are mostly large non-spherical particles. All of the results show that the air quality in Cairo and the Nile delta region is subject to a complex mixture of air pollution types, especially in the fall season, when biomass burning contributes to a background of urban pollution and desert dust

    Climatic Drivers of Potential Hazards in Mediterranean Coasts

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    This paper studies climatic drivers (air and water temperature, precipitation rates, river discharge, sea level and storm patterns) in four Mediterranean regions: the Catalan-Valencia Coast (Spain), the Oran (Algeria) and Gabe`s (Tunisia) Gulfs and the western Nile Delta (Egypt). The paper also considers the potential hazards that these drivers can induce. It first analyses climatic trends in the drivers, taking into account the available time series of recorded and simulated meteo-oceanographic data from different sources. Next, it presents the general framework to assess biogeophysical hazards (flooding, erosion, droughts and water quality), followed by a simple and yet robust evaluation of those hazards for the four studied coastal sites. Assuming climate change projections under different scenarios and considering the observed trends in drivers, the resulting erosion rates due to sea-level rise and wave storm effects have been estimated. The Nile and Ebro Deltas, together with the Oran Gulf, are more vulnerable than the Gulfs of Valencia and Gabe`s. Regarding water quality in terms of (a) precipitation and dissolved oxygen in the water column and (b) sea surface temperature, the results show that the most vulnerable zones for the projected conditions (a) are the Gulfs of Oran, Valencia and Gabe`s, while the Nile Delta is the region where the decrease in water quality will be less pronounced. For the projected conditions (b), the most vulnerable zone is the Ebro Delta, while the impact in the other three cases will be smaller and of comparable magnitude. Finally, the overall future impact of these hazards (associated to climatic change) in the four sites is discussed in comparative terms, deriving some conclusions

    CHEMICAL PROFILE OF TWO JASMINUM SAMBAC L. (AIT) CULTIVARS CULTIVATED IN EGYPT–THEIR MEDIATED SILVER NANOPARTICLES SYNTHESIS AND SELECTIVE CYTOTOXICITY

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    Objective: Evaluation of two Jasminum sambac L. (Ait) cultivars; Arabian Nights (JSA) and Grand Duke of Tuscany (JSG) ethanolic leaves extracts as reducing agents for the green synthesis of silver nanoparticles (AgNPs) and evaluation of their cytotoxicity against MCF-7 breast cancer and 5637 bladder cancer cell lines and chemical profiling of the two cultivars. Methods: The synthesis of silver nanoparticles (AgNPs) by the two cultivars and characterization of AgNPs by ultraviolet (UV)–visible spectroscopy, Transmission electron microscopy (TEM) and Fourier Transform Infrared Spectroscopy (FTIR). Additionally, the use of The high-performance liquid chromatography coupled with photodiode array-mass-mass-spectroscopy (HPLC-PDA-MS/MS) for chemical profiling of both cultivars and evaluation of total leaves extracts and corresponding nanoparticles towards MCF-7 and 5637 cell lines compared to aneuploidy immortal keratinocyte (Ha Cat) normal cells by neutral cell assay. Results: The green synthesized AgNPs (of an average size range of 8.83 and 11.24 nm for JSA and JSG, respectively) exhibited cytotoxicity against MCF-7 and 5637 cell lines. The IC50 was determined for each total extract JSA (15.29±2.16 μg/ml) and JSG (20.28±1.20 μg/ml) and corresponding AgNPs 17.32±2.22 μg/ml and 6.32±1.01μg/ml for JSA and JSG, respectively. The IC50 of JSA and JSG against 5637 bladder cancer cell line were 13.76±1.11 μg/ml and 50.69±3.75 μg/ml, while the corresponding AgNPs showed IC50 of 5.54±0.88 μg/ml and 27.89±2.84 μg/ml, respectively. The HPLC-PDA-MS/MS allowed the identification of 59 compounds; 10 simple phenols, 17 flavonoids; quercetin and kaempferol glycosides, 2 lignans, and 30 secoiridoids; oleuropein, molihauside, and sambacoside. Conclusion: This study proved that JSA is an excellent source for the synthesis of AgNPs with optimum characters and enhanced activities toward MCF-7 and 5637 cell lines in correlation to identified compounds

    Isolation of Myricitrin and 3,5-di-O-Methyl Gossypetin from Syzygium samarangense and Evaluation of their Involvement in Protecting Keratinocytes against Oxidative Stress via Activation of the Nrf-2 Pathway

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    The wax apple (Syzygium samarangense) is traditionally employed as an antibacterial and immunostimulant drug in traditional medicine. This plant is rich in different flavonoids and tannins. In this study, we isolated two compounds from S. samarangense leaves: myricitrin and 3,5-di-O-methyl gossypetin. Then, we investigated the mechanisms of action of the two compounds against oxidative stress (induced by sodium arsenite) and inflammation (induced by UV light) on human keratinocytes. We could clearly demonstrate that the pre-treatment of cells with both compounds was able to mitigate the negative effects induced by oxidative stress, as no alteration in reactive oxygen species (ROS) production, glutathione (GSH) level, or protein oxidation was observed. Additionally, both compounds were able to modulate mitogen-activated protein kinase (MAPK) signaling pathways to counteract oxidative stress activation. Finally, we showed that 3,5-di-O-methyl gossypetin exerted its antioxidant activity through the nuclear transcription factor-2 (Nrf-2) pathway, stimulating the expression of antioxidant proteins, such as HO-1 and Mn-SOD-3

    Global impacts of Covid-19 on lifestyles and health and preparation preferences: an international survey of 30 countries

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    Background: The health area being greatest impacted by coronavirus disease 2019 (COVID-19) and residents' perspective to better prepare for future pandemic remain unknown. We aimed to assess and make cross-country and cross-region comparisons of the global impacts of COVID-19 and preparation preferences of pandemic. Methods: We recruited adults in 30 countries covering all World Health Organization (WHO) regions from July 2020 to August 2021. 5 Likert-point scales were used to measure their perceived change in 32 aspects due to COVID-19 (-2 = substantially reduced to 2 = substantially increased) and perceived importance of 13 preparations (1 = not important to 5 = extremely important). Samples were stratified by age and gender in the corresponding countries. Multidimensional preference analysis displays disparities between 30 countries, WHO regions, economic development levels, and COVID-19 severity levels. Results: 16 512 adults participated, with 10 351 females. Among 32 aspects of impact, the most affected were having a meal at home (mean (m) = 0.84, standard error (SE) = 0.01), cooking at home (m = 0.78, SE = 0.01), social activities (m = -0.68, SE = 0.01), duration of screen time (m = 0.67, SE = 0.01), and duration of sitting (m = 0.59, SE = 0.01). Alcohol (m = -0.36, SE = 0.01) and tobacco (m = -0.38, SE = 0.01) consumption declined moderately. Among 13 preparations, respondents rated medicine delivery (m = 3.50, SE = 0.01), getting prescribed medicine in a hospital visit / follow-up in a community pharmacy (m = 3.37, SE = 0.01), and online shopping (m = 3.33, SE = 0.02) as the most important. The multidimensional preference analysis showed the European Region, Region of the Americas, Western Pacific Region and countries with a high-income level or medium to high COVID-19 severity were more adversely impacted on sitting and screen time duration and social activities, whereas other regions and countries experienced more cooking and eating at home. Countries with a high-income level or medium to high COVID-19 severity reported higher perceived mental burden and emotional distress. Except for low- and lower-middle-income countries, medicine delivery was always prioritised. Conclusions: Global increasing sitting and screen time and limiting social activities deserve as much attention as mental health. Besides, the pandemic has ushered in a notable enhancement in lifestyle of home cooking and eating, while simultaneously reducing the consumption of tobacco and alcohol. A health care system and technological infrastructure that facilitate medicine delivery, medicine prescription, and online shopping are priorities for coping with future pandemics

    Anion gap as bio-diagnostic index in prediction of dystocia, retained placenta and delayed uterine involution of Baladi goat (Field study)

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    Objective: To assess the anion gap (AG) validity in prediction the goat's fertility before parturition.Methods: This study was carried out on two groups (20/20, aged 4–6 years and weighted 30–43 kg) of pluriparous pregnant Baladi goats. Animals were subjected to clinical examination, blood sampling to assess serum biochemical parameters in correlation with utrasonographic assessment of uterine horn involution (UTI) and placental dropping time after kidding. Unpaired student t–test was used to detect the significance of differences (P<0.05). Correlation coefficient was used to study the relationships among the different assessed parameters, analysis (r) was assigned at P<0.05 using the same statistics program.Results: Results revealed that there were highly significant differences (P<0.05) between normally and abnormally parturated goats concerning Cl-, K+, Na+, P, Mg2+, Total/Ca2+, albumin, glucose and AG. Goats suffered from dystocia having high levels of HCO3-, cortisol and lactate. Additionally, there were significant differences (P<0.05) between normally and abnormally parturated goat does regarding the process of UTI starting from 3rd to 10th wk after parturition. Furthermore, there was a highly significant difference (P<0.05) between normally and abnormally parturated goat does concerning their placental dropping time; where, distressed/ abnormally parturated goat having the longest time. Furthermore, there were highly strong correlation coefficient between Mg2+, K+, Na+, HCO3-, glucose, albumin, AG and corrected AG concentrations during goat's prepartum period and UTI, placental dropping time.Conclusions: Reporting serum bio-chemical changes and AG during goat's prepartum period could be used as diagnostic tool to judge the normality of parturition process, placental dropping, UTI and genital health, in other word, could be used as predictor for goat's fertility prior to parturition

    Radical Scavenging Activity and Cytotoxicity of Euphorbia hirta L.

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    Euphorbia hirta L. (asthma weed, pill bearing spurge), is one of the most important species of Euphorbiaceae indigenous to Egypt and widely used in folk medicine. It was the subject for many phytochemical and biological studies but correlation between phytoconstituents and biological activities were not well studied. The aim of the present study was to correlate the antioxidant and cytotoxic activities against two of the most important health problems in Egypt with the main constituents in E. hirta (phenolic and flavonoid). The different fractions obtained from successive extraction of E. hirta were screened for their radical scavenging ability using 1,1-diphenyl-2-picryl hydrazine (DPPH) test in addition to cytotoxicity using Sulforhodamine B (SRB) assay against liver (Huh-7) and lung (A-549) cell carcinoma. Phenolic and flavonoid contents were estimated using colorimetric assays (Folin-Ciocalteu and aluminum chloride assays respectively). Ethyl acetate (EtOAc) fraction appeared as potent radical scavenger (IC50 5.4±0.65 µg/ml and IC90 11.9±0.84 µg/ml) and had the highest potency against Huh-7 (IC50 36.7±1.02 µg/ml) and A-549 (IC50 114.4 ±0.78 µg/ml) cancer cell lines. These results are attributed to the highest flavonoid concentration (23±1.06 mg/g quercetin equivalent) in EtOAc fraction in addition to high content of phenolics (88.9 ±0.57 mg/g gallic acid equivalent). Further studies are necessary to isolate and identify the ethyl acetate’s bioactive compounds and evaluation of their biological activities
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