Publication Date: 2020
Acta Universitatis Carolinae, Geographica (03005402)55(2)pp. 165-182
The knowledge of actual evapotranspiration at farm level is a prerequisite for irrigation planning, farm management, to increase production and reduce water consumption. To accomplish this, comprehensive and accurate assessment methods should be applied. In order to evaluate accurately evapotranspiration processes we compared lysimeter evapotranspiration data with MODIS (Aqua and Terra satellites) and LANDSAT (SEBAL algorithm) satellite images as well as with the FAO Penman-Montith method. The findings indicate the low error rate, high correlation (1) and appropriateness of SEBAL in estimating actual evapotranspiration. The error values MAD, MSE and RMSE between lysimeter and the SEBAL algorithm were 0.59, 0.36 and 0.60 respectively. The second best performance was established for the FAO Penman-Montith method. The obtained error values MAD, MSE and RMSE between the lysimeter and FAO-Penman-Montith method are 0.91, 1.29 and 1.13, respectively. © 2020 Karolinum - Nakladatelstvi Univerzity Karlovy. All rights reserved.
Publication Date: 2025
Theoretical and Applied Climatology (14344483)156(1)
This study analyzed Iran's trends and variations in annual precipitation (AP) from 1971 to 2015. The findings indicate that 80.9% of the nation’s territory has experienced a declining trend in AP, while only 19% has exhibited an increase. Notably, the pronounced decreasing trend is observed in approximately 33.53% of the country. Regions demonstrating statistically significant increasing trends represent merely 2.93% of the total area and appear as dispersed patches. The correlation coefficients (CC) between precipitation trends and geographical coordination-topographic variables (GCTV) were found to be relatively low. In contrast, the CC between AP trends and the amount of AP was more significant; suggesting that large-scale atmospheric forcing predominantly influences long-term trends. Furthermore, a slight decrease in the long-term trend of days with normal and extreme precipitation was identified. These types of precipitation, particularly those below the 10th and 25th percentile, appear to be more influenced by local geographic features than by large-scale atmospheric systems, resulting in a negligible relationship between their trends and the overarching trends in AP. The analysis delineates three distinct phases within the AP time series—1971–1982, 1983–1999, and 2000–2015—highlighting a recorded decline in national AP from the first phase to the final phase. Additionally, a decrease in the month-to-month coefficient of variation (MCV) of precipitation, which indicates a reduction in precipitation during the wet months, generally aligns with the spatial pattern of AP; however, some variability in the CC between GCTV and MCV was observed. The study suggests large-scale atmospheric forcing and the local features (e.g., elevation) play a significant role in Iran's AP trends and phases of AP in Iran. © The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature 2024.
Publication Date: 1996
NACE - International Corrosion Conference Series (03614409)1996
Computers provide a powerful opportunity fbr the development of teaching materials. They provide a rich interactive environment to stimulate and engage the student. The advent of computers with multimedia capabilities allows the constructor of teaching materials to show the student material from many sources; text, chart, audio, video, animal ion, simulation, sound or photographs. When these are combined with interactivity, a powerfitl learning enviroimient is created [1]. There is currently no CAL(Computer Aided Learning) or CBT(Computer Based Training) material available on the subject of corrosion and corrosion protection in concrete structures fbr ci\ ii engineering students. This paper will describe a Computer Aided Learning package intended to introduce students to the environmental degradation of concrete structures. © 1996 by NACE International.
Publication Date: 2023
Iranian Journal Of Science And Technology, Transactions Of Civil Engineering (22286160)47(4)pp. 2287-2293
Rain–wind-induced vibration in cable of cable-stayed bridges is currently a global concern. Since many parameters are effective in this phenomenon, it is difficult to repeat this phenomenon in the laboratory and its mechanism has not yet been well explained. In this paper, the phenomenon of rain–wind-induced vibration in cable of cable-stayed bridge model is studied by creating an artificial rain flow in a wind tunnel. The effect of the main factors of this phenomenon, yaw angle, on the vibration characteristics due to wind and rain for a simple cable has been studied in detail in the experiment. Reciprocal measures to reduce rain–wind-induced vibration by creating a spiral grooves on the cable have been studied. Then the effect of different grooves on rain–wind-induced vibration was tested. The results show that the presence of grooves on the cable reduces the rain–wind-induced vibration. When using these grooves in cables, care should be taken with the grooves distance, because in the average wind speed by increasing the yaw angle, the cable with a longer-distance grooves has less vibration than the cable with a short-distance grooves. With increasing wind speed, this vibration increases. © 2023, The Author(s), under exclusive licence to Shiraz University.
Publication Date: 2015
Journal Of Pharmacy And Pharmaceutical Sciences (14821826)(5)pp. 647-660
A simple, rapid, and sensitive reversed-phase HPLC method was developed and validated for determination of paclitaxel (PTX) in plasma, various organs and tumor tissues of tumor-bearing mice. Tissue specimens of liver, kidneys, spleen, lungs, heart and tumor were separately homogenized in normal saline. Plasma or tissue homogenate (250 μl) containing PTX and internal standard (diazepam) were extracted by diethyl ether (6 ml). The separation was achieved on a μ-Bondapak C18 HPLC column using sodium acetate buffer solution (0.01 M)/acetonitrile (58/42 v/v) at pH 5 ± 0.1 and flow rate of 1.9 mL/min. The effluent was monitored at 227 nm and column temperature was adjusted at 58ºC. The internal standard and PTX were eluted at 4.2 and 5.2 min, respectively and no interfering peaks were observed. Calibration curves were linear over the concentration range of 0.25-10 μg/ml of PTX in plasma and 0.3-20 μg/ml PTX in tissue homogenates with acceptable precision and accuracy (<15%). The mean recoveries of the drug after plasma extraction was 87.4% ± 3.6 while those of tissue homogenates ranged from 62.1± 4.5 to 75.5± 3.2 depending on the type of tissues studied. PTX was stable in samples with no evidence of degradation during 3 freeze–thaw cycles and 3 months storage at −70 °C. The developed HPLC method was applied to quantify PTX in the mouse plasma and tissues after intravenous administration of 10 mg equivalent PTX/Kg dose of PTX-loaded tocopherol succinate-chitosan-polyethylene glycol-folate (TS-CS-PEG-FA) micelles formulation or Anzatax® (Cremophor® EL- based formulation of PTX) to female Balb/c mice. © 2015, Canadian Society for Pharmaceutical Sciences. All rights reserved.
Publication Date: 2015
Daru Journal Of Pharmaceutical Sciences (15608115)(1)
Background: MMP-2 enzyme is a kind of matrix metalloproteinases that digests the denatured collagens and gelatins. It is highly involved in the process of tumor invasion and has been considered as a promising target for cancer therapy. The structural requirements of an MMP-2 inhibitor are: (1) a functional group that binds the zinc ion, and (2) a functional group which interacts with the enzyme backbone and the side chains which undergo effective interactions with the enzyme subsites. Methods: In the present study, a QSAR model was generated to screen new inhibitors of MMP-2 based on L-hydroxy tyrosine scaffold. Descriptors generation were done by Hyperchem 8, DRAGON and Gaussian98W programs. SPSS and MATLAB programs have been used for multiple linear regression (MLR) and genetic algorithm partial least squares (GA-PLS) analyses and for theoretical validation. Applicability domain of the model was performed to screen new compounds. The binding site potential of all inhibitors was verified by structure-based docking according to their binding energy and then the best inhibitors were selected. Results: The best QSAR models in MLR and GA-PLS were reported, with the square correlation coefficient for leave-one-out cross-validation (Q2LOO) larger than 0.921 and 0.900 respectively. The created MLR and GA-PLS models indicated the importance of molecular size, degree of branching, flexibility, shape, three-dimensional coordination of different atoms in a molecule in inhibitory activities against MMP-2. The docking study indicated that lipophilic and hydrogen bonding interactions among the inhibitors and the receptor are involved in a ligand-receptor interaction. The oxygen of carbonyl and sulfonyl groups is important for hydrogen bonds of ligand with Leu82 and Ala83. R2 and R3 substituents play a main role in hydrogen bonding interactions. R1 is sited in the hydrophobic pocket. Methylene group can help a ligand to be fitted in the lipophilic pocket, so two methylene groups are better than one. The Phenyl group can create a π-π interaction with Phe86. Conclusions: The QSAR and docking analyses demonstrated to be helpful tools in the prediction of anti-cancer activities and a guide to the synthesis of new metalloproteinase inhibitors based on L-tyrosine scaffold. © 2015 Abbasi et al.; licensee BioMed Central.
Publication Date: 2017
Geography, Environment, Sustainability (25421565)10(4)pp. 43-68
Sediment monitoring and assessment remain one of the most challenging tasks in fluvial geomorphology and water quality studies. As a response to various environmental and human disturbance effects, the main sources and pathways of the sediments transported within catchments, especially most pristine small one, may change. The paper discusses state-of-the-art in the sediment budget research for small catchments. We identified nine independent approaches in the sediment transport assessment and applied them in 11 catchments across Eurasia in the framework of an FP-7 Marie Curie-International Research Staff Exchange Scheme in 2012-2016. These methods were classified as: i) Field-based methods (In-situ monitoring of sediment transport;-Soil morphological methods and dating techniques; Sediment source fingerprinting; Sediment-water discharge relationships), ii) GIS and remote sensing approaches (Riverbed monitoring based on remote sensing/historical maps; parametrization of the channel sediment connectivity; Sediment transport remote sensing modeling), and iii) Numerical approaches (Soil erosion modeling and gully erosion (stochastic and empirical models); channel hydrodynamic modeling). We present the background theory and application examples of all selected methods. Linking fieldbased methods and datasets with numerical approaches, process measurements as well as monitoring can provide enhanced insights into sediment transfer and related water quality impacts. Adopting such integrated and multi-scale approaches in a sediment budget framework might contribute to improved understanding of hydrological and geomorphological responses. © 2017, Lomonosov Moscow State University. All rights reserved.
The metabolically active tumor cells may be characterized by a pronounced adenosine release that regulates the growth and development of the tumor. Consequently, the expression pattern of defined receptor subtypes will be an important determinant for specific effects of adenosine on the control of tumor cell growth. In recent studies, the expression profile, signal transduction, molecular function and cell growth modulation of adenosine receptors in the human breast cancer cell lines has been reported. To investigate the possible roles of adenosine receptors in other types of human cancers, in this study, we characterized the expression profile of adenosine receptors in two different human cancer cell lines: prostate carcinoma cell line (Du-145) and lung adenocarcinoma cell line (Calu-6). Our purpose is to test the hypothesis that diverse human cancer cell lines, according to their adenosine receptor subclass status, would show differential growth modulation. Methods: RNA was extracted and reverse transcribed to cDNA. PCR primers were synthesized from human adenosine receptor cDNA sequences. PCR was performed under optimized condition for each receptor subtype. The PCR products were separated on agarose gels. Results: All two human cancer cell lines studied contained detectable amounts of mRNA specific for adenosine receptor except A3 subtypes. Conclusion: In conclusion the differentially expressed genes identified in this study might provide new insights into the possible roles of adenosine receptors on cell growth and development.
Publication Date: 2025
Natural Hazards (0921030X)121(2)pp. 1353-1373
The increase in the concentration of greenhouse gases(CO2) emission in the atmosphere, and natural climate change phenomena has caused unprecedented changes in global climate behavior. The sharp increase in temperature and extreme weather events like drought in arid and semi-arid countries like Iran have reduced the resilience of ecosystems, thus, environmental stability. The objective here is to analyze the causality of air temperature rise trend and drought, by assessing their consequences on water tension and internal migration, next to providing appropriate solutions in reducing environmental vulnerability in Iran through the Driving Force-Pressure-State-Impact-Response (DPSIR) model. It is revealed that the air temperature in Iran is increasing at a rate faster than the global average. The simultaneous rise in temperature, the decrease in precipitation, and the occurrence of long-term droughts have increased water tension and reduced the stability of settlements. Reduced water resources have increased poverty and internal migration in Iran. Reducing the intensity of fossil fuel consumption and CO2 emission, through adaptation methods and improving the spatial distribution of the population are among the proposed responses for adjusting the water tension effects and reducing vulnerability. © The Author(s), under exclusive licence to Springer Nature B.V. 2024.
Publication Date: 2019
Cell and Tissue Banking (15736814)(3)pp. 423-434
Nowadays, Mesenchymal stem cells (MSCs) have become one of the most attractive tools for treating tumors, due to their specific characteristics, the most prominent of which are tropism toward tumor. These cells will exert their effects through their secretion. In this study, our aim was to evaluate the anti-cancer effect of umbilical cord-derived mesenchymal cells (UCMSC) secretome, on MCF-7 tumor cells. MSCs were extracted from the umbilical cord of mothers, having normal delivery or cesarean section. After culture, the supernatants of these cells were collected and freeze-dried. The cytotoxic effect of freeze-dried secretome was examined at different concentrations on MCF-7 and the optimum concentrations (IC50) were calculated, using MTT assay. These results were confirmed by BrdU assay. The effect of induction of apoptosis of the MSC secretome on MCF-7 was determined, using annexin V/PI method by flow cytometry. The results of our study indicate that the isolation and growth time of UCMSCs of mothers who were naturally delivered was lower than those who received cesarean section. Co-culture studies showed that MSCs had cytotoxic effects on MCF-7 cells. The MSC secretome also showed cytotoxic effects on the MCF-7 cell line, this effect was mediated by induction of apoptosis, which was dose-dependent with an IC50 of 10 mg/mL. © 2019, Springer Nature B.V.
Publication Date: 2021
Water (Switzerland) (20734441)13(9)
Model evaluation against experimental data is an important step towards accurate model predictions and simulations. Here, we evaluated an energy-balance model to predict dew formation occurrence and estimate its amount for East-African arid-climate conditions against 13 months of experimental dew harvesting data in Maktau, Kenya. The model was capable of predicting the dew formation occurrence effectively. However, it overestimated the harvestable dew amount by about a ratio of 1.7. As such, a factor of 0.6 was applied for a long-term period (1979–2018) to investigate the spatial and temporal variation of the dew formation in Kenya. The annual average of dew occurrence in Kenya was ~130 days with dew yield > 0.1 L/m2/day. The dew formation showed a seasonal cycle with the maximum yield in winter and minimum in summer. Three major dew formation zones were identified after cluster analysis: arid and semi-arid regions; mountain regions; and coastal regions. The average daily and yearly maximum dew yield were 0.05 and 18; 0.9 and 25; and 0.15 and 40 L/m2/day; respectively. A precise prediction of dew occurrence and dew yield is very challenging due to inherent limitations in numerical models and meteorological input parameters. © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).
Publication Date: 2022
Building Services Engineering Research and Technology (14770849)43(4)pp. 485-506
Design coordination and clash detection are the most common and appreciated applications of three-dimensional modeling (3D modeling). In some projects, millions of clashes are detected including a large number of irrelevant clashes. The purpose of this research is to determine the priority of resolving clashes before the construction phase. In this research, the results of Autodesk Navisworks have been used to improve the process of clash detection. Also, this study attempts to use the fuzzy-AHP for weighting criteria and then, by presenting a relationship, to provide a basis to prioritizing clashes for their resolution and, finally, for identifying irrelevant clashes. This method has been tested on a real project, and the comparison of the expert opinions and the proposed method showed that applying the proposed relationship can identify important and irrelevant clashes. Practical application: If clashes are not carefully detected in the design stage, project management components face a serious challenge. In this study, using the weight of clash elements and the degree of penetration of clash elements into each other, a logical and practical relationship is presented that improves the process of clash detection. © The Author(s) 2022.
Publication Date: 2020
International Journal of Biological Macromolecules (01418130)pp. 220-229
Hydrogel scaffolds have been frequently utilized due to their ability to absorb water and develop similar body cell conditions. Specific drug delivery to the tissues ensures less adverse side effects and more efficiency. In the present study, carboxymethyl chitosan (CMC)-methylcellulose (MC)-pluronic (P) and zinc chloride hydrogels containing meloxicam loaded into nanoparticles were developed and characterized. Nanoparticles were incorporated at 3.5, 4.5 and 5.5% (w/v). Hydrogels containing the same amounts of the meloxicam solution were also prepared. Gelation time, swelling and degradation of the hydrogels were investigated. Hydrogels were characterized by scanning electron microscopy (SEM), attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, and rheological analysis. Meloxicam release, chondrocytes attachment and growth on the hydrogels were also studied. Gelation time, swelling and the degradation rate of the hydrogels were found to be decreased by nanoparticles and increased with the addition of the meloxicam solution. SEM images also showed three-dimensional networks. The ATR-FTIR bands were shifted to the lower wave numbers in the hydrogels containing nanoparticles and shifted to the upper ones in the hydrogels containing meloxicam solution. Storage (G′) and loss (G″) modulus were increased by the nanoparticles and reduced by the meloxicam solution. 100% of meloxicam was released from the hydrogels containing the meloxicam solution within 20 days, but it was released slowly from the hydrogels containing nanoparticles in 37days. Chondrocytes metabolic activity was increased on the 6th and 10th days for all hydrogels. Hydrogel containing nanoparticles showed good biocompatibility, bioadhesion, cell growth and expansion. The hydrogel could be, therefore, suitable as a new composite biomaterial for the regeneration of articular cartilage and meloxicam delivery to control the pain and inflammation in osteoarthritis. © 2020 Elsevier B.V.
Publication Date: 2021
Iranian Journal Of Pharmaceutical Research (17350328)(4)pp. 125-136
The coronavirus disease-2019 (COVID-19) was first recognized in Wuhan, China, and quickly spread worldwide. Between all proposed research guidelines, inhibition of the main protease (Mpro) protein of the virus will be one of the main strategies for COVID-19 treatment. The present work was aimed to perform a computational study on FDA-approved drugs, similar to piperine scaffold, to find possible Mpro inhibitors. Firstly, virtual screening studies were performed on a library of FDA-approved drugs (43 medicinal compounds, similar to piperine scaffold). Among imported 43 drugs to virtual screening, 34 compounds were extracted. Four top-ranked drugs in terms of the highest interactions and the lowest binding energy were selected for the IFD study. Among these selections, lasofoxifene showed the lowest IFD score (-691.743 kcal mol-1). The stability of lasofoxifene in the COVID-19 Mpro protein active site was confirmed with 100 ns MD simulation. Lasofoxifene binding free energy was obtained-107.09 and-173.97 kcal mol-1, using Prime MM-GBSA and g_mmpbsa methods, respectively. The identified lasofoxifene by the presented computational approaches could be a suitable lead for inhibiting Mpro protein and COVID-19 treatment. © 2021, Briefland. All rights reserved.
Publication Date: 2015
Natural Hazards (15730840)79pp. 25-50
Soil erosion by water is a significant problem in arid and semi-arid areas of large parts of Iran. Water erosion is one of the most effective phenomena that leads to decreasing soil productivity and pollution of water resources; especially, in the Mazayjan watershed in the southwest of Fars Province gully erosion contributes to the sediment dynamics in a significant way. Consequently, the intention of this research is to identify the different types of soil erosion processes acting in the area and to assess the process dynamics in an integrative way. Therefore, we applied GIS and satellite image analysis techniques to derive input information for the numeric models. For sheet and rill erosion the Unit Stream Power-based Erosion Deposition Model (USPED) was utilized. The spatial distribution of gully erosion was assessed using a statistical approach, which used three variables (stream power index, slope, and flow accumulation) to predict the spatial distribution of gullies in the study area. The eroded gully volumes were estimated for a 7-year period by fieldwork and Google Earth high-resolution images. Finally the gully retreat rates were integrated into the USPED model. The results show that the integration of the SPI approach to quantify gully erosion with the USPED model is a suitable method to qualitatively and quantitatively assess water erosion processes. The application of GIS and stochastic model approaches to spatialize the USPED model input yields valuable results for the prediction of soil erosion in the Mazayjan catchment. The results of this research help to develop an appropriate management of soil and water resources in the southwestern parts of Iran. © 2015, Springer Science+Business Media Dordrecht.
Publication Date: 2013
Journal of the Earth and Space Physics (25383906)38(4)pp. 241-258
In different regions, precipitation takes place with different persistencies and every persistency supplies a share of rainfall days and precipitation. Therefore, the importance of rainfall persistence could be evaluated in all places. Iran is located in Mid-Latitude of an arid region, in which the mean rainfall is 250 mm and it has dramatic tempo-spatial changes. Rainfalls with short persistence are of characteristics of arid regions and it is also tangible in Iran. However, Iran's rainfalls persistence ranges from 1 to 45 days and have dramatic tempo-spatial changes, but the maximum amount and days of rainfalls are supplied by rainfalls with short persistency. So, the phenomenon of rainfalls with long persistency is considered as an extreme event which has extreme variability. As the persistence of precipitations increases, their role in generating Iran's rainfall days decreases severely in such a way that the maximum rainfall days of Iran is supplied by one-day rainfalls. However, the share of one-day rainfalls in the supply of precipitation days of Iran's Western half is more accentuated. In contrast, the increase in the persistence of rainfalls does not have an identical role in decreasing the supply of Iran's precipitation. As the persistence of precipitations increases, the share of precipitation in the Central and Southwestern Iran decrease severely, but in Western and Northern Iran, vice versa is the case. In some heavy precipitation regions of Iran's Western half, the decrease of precipitation persistence is associated with the decrease of the share of precipitation supply and in other regions; the decrease of the share of precipitation supply is gradual. Therefore, in every space, some of the persistent rainfalls supply the great share of precipitation days and precipitation amount and are considered important. However, it is possible that this precipitation persistency do not have such importance in those areas. Every kind of variability and change in the role of precipitation persistence in every space will be considerable. Spatial changes of one-day precipitation's share in the supply of Iran's precipitation days and precipitation amount could be evaluated from this angle. To evaluate the changes in one-day precipitation' share in the supply of precipitation days and precipitation amount, the daily observations of precipitations in 1437 stations of throughout Iran was used. Drawing upon Kriging method, the observations of the stations were generalized in a regular network by 15*15 km dimensions and Iran's isotheral digital maps were developed from 1961/03/21 till 2004/12/30. These digital maps include daily time series (15991 days) of precipitation amount for 7187 cells. Precipitation persistence in the time series of every cell was evaluated and in addition to that, their share in the supply of precipitation days and precipitation amount of each cell were also calculated. Then, the most important persistence of Iran's precipitations (one-day persistence) was identified and their importance was investigated. Yearly and monthly time series of one-day precipitation' share in the supply of precipitation days and precipitation amount were entered in a trend analysis for evaluating and understanding its changes and its results were considered. In spatial analyses including identification of climatologically variables trend, more confident way is that firstly, spatial interpolation is done; then, an appropriate trend test is performed on the data on the nodes. The results obtained from such analyses not only enjoy higher degree of spatial attribution, but based on closeness principle, spatial order of points themselves provide intuitional reason for accepting or rejecting trend analysis. One-day precipitations supply more share of Iran's precipitation days compared to remaining precipitation persistencies in such a manner that it may be noted that in all regions of Iran, the frequency of one-day precipitations is maximum compared to remaining precipitation persistence. In contrast, Iran's precipitation is provided by different persistencies and the share of one-day precipitations in precipitation supply is maximum only in Western half (Central and Southeastern parts). However, although oneday precipitations do not have much importance throughout Iran, the degree of their importance in Eastern half is maximum compared to Western half. The share of on-day precipitations in the supply of Iran's precipitation days and precipitation amount has changed with time. The results of yearly changes of share of on-day precipitations in the supply of Iran's precipitation days and precipitation amount indicate that their share in the supply of precipitation days decreases in one quarter of Iran's area and only in 3% of Iran's area, their share increases. Given that Western and Central Iran's maximum precipitation days are provided by one-day precipitations, precipitation days of Eastern Iran have decreased. In addition, their share in the supply of precipitation days decreases in 1/5 of Iran's area and only in 6% of Iran's area, their share has increased. On the other hand, Given that Central Iran's maximum precipitation days are provided by one-day precipitations, their share in the supply of precipitation days has decreased; just in discrete regions and along with Zagros and Alborz unevennesses, their share increases. The results of yearly changes of share of one-day precipitations in the supply of Iran's precipitation indicate that their negative trend in all rainfall months is greater than their positive trend. Looking more generally into the share of monthly changes of one-day precipitations in the supply of Iran's precipitation, the aspects of Iran's precipitation concentration becomes evident, especially in Eastern and Central Iran.
Publication Date: 2023
Environmental Earth Sciences (18666280)82(8)
Anomalies and concentrations of winter precipitation are effective in the challenges regarding water shortage. Iran's precipitation is strongly influenced by teleconnection, where changes in SLP (sea level pressure), SST (sea surface temperature), and 500 hpa levels contribute highly to the temporal distribution and precipitation volume. The effect of the SST, SLP, and 500 hpa, 2.5°× 2.5° factors are assessed from 1984 to 2018. The results indicate that a decrease in the Red Sea pressure (Sudan Low) and the Pacific Ocean and an increase in the Atlantic and Indian oceans’ pressures increase Iran's winter precipitation. At 500 hpa level, the results reveal that the increased winter precipitation in Iran is associated with an increase of 500 hPa in altitude on the Baltic Sea and the Indian Ocean and a decrease in altitude of 500 hpa on the Caspian Sea, the Mediterranean Sea, the Arabian Sea, and the Red Sea. In SST, the results indicate that the linkage between SST and precipitation of Iran is positive in regions of the Arabian and Red sea, Madagascar, and north Atlantic Ocean regions. Any change in SLP, 500 hPa level, and SST introduces positive or negative anomalies in Iran's precipitation. Global warming, which changes SLP, atmospheric thickness (1000–500), and SST, has a greater impact on Iran's precipitation, thus challenging water resources and facing climate risks. © 2023, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.
Publication Date: 2023
The Egyptian Journal Of Remote Sensing And Space Sciences (11109823)26(3)pp. 851-861
In recent decades, severe climate change, decreased precipitation, temperature rise, and increased evapotranspiration (ET) have significantly reduced waterbodies. Furthermore, governments have prioritized the study of water level fluctuations of lakes to protect them from degradation nationally and regionally. The present study investigated the physical changes in lakes Bakhtegan and Tashk due to climatic parameters. To this end, Landsat satellite imagery and the NDWI were employed to calculate the area of the waterbodies from 1986 to 2018. The results showed that the area had decreased during the study period– since 2009, Lake Bakhtegan had dried up completely. In 2008 and 2010, the lowest precipitation was 127.82 and 107.7 mm, respectively. During the study period (1986 to 2018), the average temperature was 19.44 °C, with an increase of 0.6 °C. Among the climatic parameters, precipitation, with a correlation coefficient of 0.55, and potential evapotranspiration (PET), with a correlation coefficient of about −0.68, were more strongly correlated with changes in the area of the waterbodies. To predict temperature and precipitation in the study area in the coming decades (2020–2050), the HadCM2 model of the CORDEX Project -WAS (South Asia) was used under two scenarios: RCP4.5 and RCP8.5. These scenarios revealed the decrease in precipitation and increase in temperature trends. As a result, the waterbodies’ areas were estimated using the projected precipitation and PET for the period 2050–2020, indicating a decrease in the areas of the waterbodies. © 2023 National Authority of Remote Sensing & Space Science
Publication Date: 2022
The Egyptian Journal Of Remote Sensing And Space Sciences (11109823)25(4)pp. 1069-1088
In recent years, climate change has caused an increase in the air temperature and consequently the temperature of the earth's surface. The temperature of the earth's surface has had various effects on urban life and has caused the formation of thermal islands in cities. Thermal islands are one of the important criteria in regional planning. The city of Shiraz is considered to be a large population center in the southwest of Iran on the one hand and one of the important tourism centers of Iran on the other hand, so the purpose of this research is to monitor the spatial form of thermal islands in this city. The satellite images of Shiraz city were first collected and extracted in the hot periods of the year from 1985-to 2020 using the data of Landsat's 4 and 5 (TM), 7 (ETM+), and 8 (OLI/TIRS). After required preprocessing, the Normalized Difference Vegetation Index (NDVI), Land Surface Temperature (LST), Normalized Difference Built-up Index (NDBI), and the urban heat dispersion index were determined by the Urban Thermal Field Variance Index (UTFVI). The regions with UHI, the variation of the temperature in the city, and the relationship between the LST and surface vegetation were evaluated based on the results of image processing to determine the UHIs of Shiraz. The temporal variations of the temperature pattern of Shiraz city indicated that about 12.76 km2 was added to the area of the fourth temperature class from 1985 to 2020. Results of NDVI evaluation in the studied period showed a decline in the vegetation from 22.28 km2 in 1985 to 17.54 km2 in 2020 due to alteration of the land use which can explain the formation and increase of the UHIs in the mentioned regions. At the beginning of the investigated period (1985), the temperature of the earth's surface was 17°Celsius and reached 21°Celsius at the end of the period (2020). The monitoring of the spatial form of the surface temperature of the earth shows that heat islands are moving from the outskirts of the city towards the city center. UTFVI also revealed that the awful regions (very hot temperatures) are mainly concentrated in the west and north-west to the south west of Shiraz (including some parts of districts 9 and 10), south east of district 7, and north of district 1. © 2022 National Authority of Remote Sensing & Space Science
Publication Date: 2022
Iranian Journal of Remote Sensing and GIS (25886185)13(4)pp. 35-50
The expansion of urbanization and the increase of population in metropolises and the growth of industrial activities of cities, It has caused changes in urban area climate. One result of these changes is the city's heat islands. The city of Mashhad has also grown rapidly in recent years. This study investigates the heat/cold island of Mashhad metropolis based on the background climate in order to identify its spatiotemporal behavior. For this purpose The MODIS Terra and Aqua land surface temperature (LST) data were obtained and the heat island was examined accordingly. A new was used to measure the heat island. In this method, Modis land use data was used to determine the urban and suburban boundaries as well as to determine the land use type of the study area. The background climate was determined based on Far-side temperature and the representative non urban area was selected based on the most frequent temperature and the heat island was calculated. Survey of heat/cold island in the daily period showed that during the day the average temperature of city is lower than non urbun temperature and at night is higher. Also the seasonal survey of heat island/could island of Mashhad metropolitan shows that daily cold island is the highest during the warm seasons and lowest in the cold seasons and the seasonal variability of nightly heat island is less than the daily cold island. The core of the daily cold island is located between the Haram and the Shahid Fehmidah Square towards the western area of Mashhad. The day time cold island matches the areas of the city with high vegetation coverage. The core of the nightly heat island is consistent with the old texture and dense area around the Haram towards the northwest of the city. The heat/cold island intensity is also directly related to the wind speed. The role of land use in intensifying or reducing the intensity of the heat island of Mashhad is well seen. In the development of the city, more attention can be paid to the use of urban land use in order to moderate the temperature of the city. © 2022, Shahid Beheshti University. All rights reserved.
Publication Date: 2016
Atmospheric Research (01698095)169pp. 96-101
We analyzed spatial and temporal patterns in temperature extremes from 31 stations located throughout Iran for the period 1961 to 2010. As with many other parts of the globe, we found that the number of days (a) with high maximum temperatures was rising, (b) with high minimum temperatures was rising, and (c) with low minimum temperatures was declining; all of these trends were statistically significant at the 0.05 level of confidence. Population records from 1956 to 2011 at the station locations allowed us to reveal that the rate of human population growth was positively related to the increase in the number of days with high maximum temperatures and negatively related to days with low maximum temperatures. Our research shows a number of identifiable anthropogenic signals in the temperature records from Iran, but unlike most other studies, the signals are stronger with indices related to maximum, not minimum, temperatures. © 2015 Elsevier B.V.
Publication Date: 2019
Research on Chemical Intermediates (09226168)(5)pp. 2827-2854
Based on the structural elements of bioactive 3-substituted indoles, a new series of indole–thiosemicarbazone hybrid derivatives were designed, synthesized, and well-characterized using different spectral techniques. The intended scaffolds were screened for their in vitro anti-proliferative activities against breast cancer (MCF-7), lung cancer (A-549), and liver cancer (Hep-G2) cell lines, as well as their anti-oxidant properties. Cytotoxicity studies revealed that compound 6n was the most potent, at least threefold more potent than the commercially available reference drug etoposide, against A-549. In addition, morphological analysis by the acridine orange/ethidium bromide double staining test and flow cytometry analysis confirmed induction of apoptosis in the A-549 cells by compound 6n. In order to validate the experimental results, molecular studies were performed to achieve the possible binding interactions of the most potent compound (6n) and colchicine with tubulin as well as ANP with ATPase domain of topoisomerase IIα active sites. Moreover, the radical scavenging potential of the final derivatives was found to be excellent with the range of 0.015–0.630 µM, comparable to the standard ascorbic acid (0.655 µM). © 2019, Springer Nature B.V.
Publication Date: 2013
Iranian Journal Of Basic Medical Sciences (20083874)16(11)pp. 1203-1208
Objective(s): Regarding the presence of many active biological constituents in Avicennia marina, the present investigation was carried out to study cytotoxic activity of crude methanol leave extract and column chromatographic fractions of A. marina against MDA-MB 231 cell line (human breast cancer cell) and HEK (Human embryonic kidney cell) line. Materials and Methods: The anticancer activity of crude methanol extract and sub-fractions were evaluated, using MTT assay. The induction of apoptosis was determined by analyzing DNA fragmentation in breast cancer cells treated with active fraction of crude methanol extract using agarose gel electrophoresis. To investigate molecular mechanism of apoptosis, gene expression levels of p53 and Bcl-2 were measured using quantitative real time PCR. Results: Fraction 10 was the most active fraction and was detected with HPLC as luteolin. The 50% cell cytotoxic concentration (CC50) of crude methanol extract and luteolin was 250 and 28 μg/ml, respectively. This fraction was found to be an apoptotic agent against MDA-MB 231 cells, which leads to causing DNA fragmentation. The mRNA expression level of Bcl-2 and p53 was significantly decreased and increased respectively in cancer cells treated by luteolin. Conclusion: The results suggested that Luteolin isolated from Avicennia marina could probably induce apoptosis on breast cancer cell line by the regulation of p53 and Bcl-2 pathways.
Deserts exist on every continent of the globe and cover more than 30% of the Earth's land surface. Although they typically do not have a large number of inhabitants, they are often the loci of economic and cultural activity. For example, the oil-producing nations of the Middle East are all found within a single arid region. At the same time, deserts tend to be fragile ecosystems, requiring little in the way of perturbations in order to cause tremendous changes in the landscape. The size, remoteness, and harsh nature of many of the world's deserts make it difficult and expensive to map or monitor these landscapes or to determine the effect of land use on them. Remote sensing is potentially a time- and cost effective way to fulfill these goals. In this research, we will discuss the uses and limitations of remote sensing in the world's deserts. The discussion will center on using remote sensing to detect and monitor landscape change and degradation in arid regions. Because vegetation is often linked to both the causes and consequences of arid land degradation, our discussion will further focus on the retrieval of vegetation parameters. In this paper, examples of successful applications of remote sensing to arid regions are given. Also, limitations and important considerations of remote sensing in arid regions are discussed. Ultimately, atmospheric remote sensing as it relates to land degradation in arid regions is discussed. And, a case study is presented in which various methods for estimation of vegetation cover are presented and compared.
Publication Date: 2015
Advances in Environmental Biology (19950756)9(3)pp. 585-595
One of the greatest and the most widespread of the parts in recent decades many of the planners and local and regional managers to attract has tourism section especially tourism based on the enjoyment of the natural phenomenon of the courage it can be said in recent decades has had noticeable growth and has managed not only as a thriving industry with their not under many parts of divided This research as an assessment and determine the strategy of the strategic management Geomorphotourism Awramanat region in the west country with the purpose of developing the land and tourism this region With the use of the method is a descriptive studies and making use of the documents has been prepared. The data used in this research as well as with the use of the questionnaire instrument and making use of experts and the experts had been collected and with the use of the strategic model swot analysis. results of these surveys and the use of the strategic management model (swot) for this region showed that performance of executive strategy Geomorphotourism Awramanat region in the options of the preserve, abandon and growth and development with regard to the potential of the high capacity and potential in the field to Geomorphotourism existence ghorighale cave, zribar Lake, the river Sirvan, mirage Ravansar, waterfalls and springs of the very rich and many glacier, landforms mountainous and plain landforms and... The third option-necessity of growth and development of this region. © 2015 AENSI Publisher All rights reserved.
Publication Date: 2022
Watershed Engineering and Management (22519300)14(1)pp. 40-54
The protection and management of each user in different areas should be based on ecological conditions, which can be achieved by assessing the ecological potential in each area. Assessing ecological potential means examining the potential power of the land and determining its natural use by humans. The main purpose of this study is to identify the ecological potential in Khodaafarin City with an area of 161,607 ha, using the multi-criteria assessment method, the common land management model of Dr. Makhdoom and using GIS. In this study, after identifying ecological resources (sustainable and unstable), the resources were analyzed and summarized. Then, in the software environment (ArcGIS 10.6), the information layers were combined and then the maps were evaluated. Finally, according to the existing values, the potential strengths and bottlenecks of the region were estimated and the permitted uses were prioritized in the region. As a result, after combining the necessary maps and correcting them, the environmental capacities and ecological potential of the region were estimated as area (percentage) in Khodaafarin City. According to the objectives of the research, areas prone to segregation of aquaculture-agriculture (2.65), aquaculture-rangeland management (0.14), aquaculture-urban and rural development (0.2), aquaculture-extensive tourism (0.049), conservation-extensive tourism (0.45), conservation-forestry (0.12), centralized tourism-forestry (0.021), aquaculture (6.34), extensive tourism (12.61), centralized tourism (2.64), rangeland management (33.1), agriculture (7.51), conservation (13.57), urban, rural and industrial development (1.8), forestry (18.8) were zoned and identified. The results also showed that the highest potential is related to the rangeland management with an area of 61567.55 ha of which less than 50% (30457 ha) is consistent with the current conditions. © 2022, Soil Conservation and Watershed Management Research Institute, All rights reserved.
