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In this study, the combination of the conventional membrane bioreactor (MBR) process with attached growth system using moving bed (MBMBR) and fixed bed (FBMBR) for simultaneous removal of organic carbon, nitrogen, and phosphorus from wastewater was carried out at a pilot-scale application. The effluent was monitored daily for COD, NO3, PO4, and pH concentrations to achieve COD removal and nitrogen and phosphorus stabilization. After achieving equilibrium, sampling was done twice a week from the raw wastewater tank, aerated reactor, and effluent. Various parameters including MLSS, MLVSS, SVI, nitrate, and total phosphorus were measured by standard methods and the effects of variables such as retention time and optimal conditions were investigated in the MBMBR and FBMBR reactors. The results showed that the membrane fouling rate in the MBMBR reactor was higher than that in the FBMBR reactor; and the nitrogen and phosphorus removal efficiency in the FBMBR reactor was significantly higher than that in the MBMBR reactor. The combined MBR process with a fixed and moving bed depicted a suitable capability for removing organic carbon, nitrogen, and phosphorus. It was found that the membrane bioreactors benefited from a higher efficiency, especially the FBMBR reactor, in removing parameters such as phosphorus, nitrogen, and organic matter compared to the MBMBR reactor. In general, it can be concluded that the type of biofilm carrier medium affects membrane fouling and sludge filterability. [ABSTRACT FROM AUTHOR]

In the present study, fifty genotypes were evaluated over 5 years. The analysis of variance revealed significant interaction (P < 0.001) between genotype and year (GYI). The results of different stability statistics illustrate that the Kang's rank-sum is a good statistic and based on that, Azadi, Roshan, Mahdavi, Marvdasht, and Naz identified as desirable cultivars. Seven environmental factors including maximum temperature, minimum temperature, average temperature, precipitation, relative humidity, daylight hours, and soil temperature over eleven twenty-day periods and sixteen molecular markers associated with vernalization and photoperiod were used as covariates to interpret the interaction. The Partial least square regression biplot with environmental covariates explained 28.23% and with genotypic covariates explained 40.24% of the GYI. The results also showed that genotypes do not respond similarly to environmental variables at different stages of development. Genotypes have been classified into three groups, the first group being more related to environmental factors at the end of the growing season, the second group being more influenced by environmental factors at the beginning of the season, and the third group being genotypes of environmental factors throughout the season, especially the mid-season was affected. Among environmental factors, relative humidity except for period 9 had a special role in GYI in all periods. On the other hand, Ppd.D1D001.KASP, Vrn.B1.B.KASP, Inter1.D.deletion, VRN.A1, Vrn.A1.E7.FT.KASP and Vrn.A1.E4.vern.KASP markers had the most impact on the GYI among the different molecular markers. This information on the causes of the GEI can be useful in future breeding and management programs. [ABSTRACT FROM AUTHOR]

Understanding the genetic basis of performance stability is essential to maintain productivity, especially under severe conditions. In the present study, 268 Iranian bread wheat landraces and cultivars were evaluated in four well-watered and two rain-fed conditions for different traits. According to breeding programs, cultivars were in a group with a high mean and stability in terms of GY, GN, and SW traits, while in terms of PH, they had a low mean and high stability. The stability of cultivars and landraces was related to dynamic and static stability, respectively. The highest number of marker pairs and lowest LD decay distance in both cultivars and landraces was observed on the B genome. Population structure differentiated indigenous cultivars and landraces, and the GWAS results for each were almost different despite the commonalities. Chromosomes 1B, 3B, 7B, 2A, and 4A had markers with pleiotropic effects on the stability of different traits. Due to two rain-fed environments, the Gene Ontology (GO) confirmed the accuracy of the results. The identified markers in this study can be helpful in breeding high-performance and stable genotypes and future breeding programs such as fine mapping and cloning. [ABSTRACT FROM AUTHOR]

The present paper intends to reconstruct temporal-spatial patterns of below − 15 °C cold waves in the northwest of Iran and carry out a synoptic analysis of the patterns of these cold waves. Carrying out research on this topic can assist researchers and the state authorities in solving problems of different spheres of society, such as agriculture, economics, public health, etc., since cold waves can affect health problems in society and frosts can inflict severe damages to the agricultural crops and thereby lead to serious economic losses. For the purpose of this paper, a data corpus related to a period of 142 years from 1871 to 2012 was obtained from the relevant twentieth-century data banks of NOAA. Having sorted out the relevant data, cold waves of − 15 °C as well as cold waves of below − 15 °C were identified in the first place. Then, the identified cold wave patterns were classified and synoptically analyzed. The results revealed that, at the sea level, high-pressure waves from Siberia, west and northern regions coupled with the atmospheric blockings and the northern airflow in the upper levels of the atmosphere, led to transition of cold waves from northern latitudes to the northwest regions of Iran, resulting in very intense and long-lasting cold waves. [ABSTRACT FROM AUTHOR]

The goal of the present study is to provide a climatic description of spatiotemporal variations of cloud fractions based on geographic characteristics over Iran during daytimes. Analyses are performed on the basis of 15 years of data collected from the MODIS instrument aboard Terra and Aqua satellites, data from 120 weather stations, ERA-Interim reanalysis, and geographic data (latitude, altitude, and vegetation cover). We have compared the consistency of MODIS monthly mean of cloud fractions aboard the Terra and Aqua with ERA-Interim and weather stations data. The results showed good agreement (R2 = up to 74 % ) between them but the data is more consistent during the cold months. Weather station data has a better overall agreement with MODIS compared to ERA-Interim. Temporal variations of cloud fraction showed maximum standard deviation in autumn for both satellite observations. Trend analyses applied to both data indicate non-significant trends for most months, although a significant decreasing trend of 2.2% per year during December and an increasing trend of 2.1% per year during May were observed. We found that the maximum and minimum monthly means of cloud fraction correspond to December to February (56 to 63%) and June-July-September (8 to 26%), respectively. Analysis of latitudinal forcing on cloud fraction showed that an increase in cloud fraction is coupled with an increase in latitude; this pattern is true only up to 31.5° N in summer. The reverse pattern is related to the Asian Monsoon system over Iran in low latitudes. Topographic forcing in this mountainous area often leads to orographic convection in the elevations of 500-1500 m during spring and autumn and coastal convection during summer. Vegetation also has a strong positive correlation with cloud fraction. [ABSTRACT FROM AUTHOR]

Peppermint ( Mentha piperita) is known as an important medicinal plant throughout the world. In the present study, after exposing peppermint plants under drought stress, the qRT-PCR was use to analyze the expression of genes involved in menthol biosynthesis pathway and encoding: limonene synthase ( lS), limon-3-hydroxylase ( l3oh), trans-isopiperitenol dehydrogenase ( ipd), isopiperitenone reductase ( ipr), pulegone reductase ( pr), menthol dehydrogenase ( mdeh), and menthofuran synthase ( mfs), which also evaluated the morphological and physiological traits. The results revealed that due to water stress, the gene expression levels of ipd, ipr, and mfs were increased, whereas the gene expression level of pr and mdeh was decreased under water stress conditions. The most of essential oil components (menthol, menthofuran, and plugene), which were analyzed by gas chromatography-mass spectrometry (GC-MS), was positively correlated with genes expression. Drought stress decreased morphological and induces increasing contents of pulegone and menthofuran and reduction in menthol percentages. Results from this study suggest that up-regulation of mfs might contribute to the altered of menthofuran as well as down-regulation of mdeh might cause the reduction of menthol. Furthermore, increasing ls gene expression levels might induce more essential oil yield, while reduction of mfs gene expression levels causes an improvement of essential oil quality. [ABSTRACT FROM AUTHOR]

This study analyzes the total ozone column (TOC) variability over the Iranian plateau (Esfahan) from 1978 to 2011. Results show that the annual average of TOC in Esfahan tends to decrease with time, which is strongly dependent on the season, with maximum values during the winter-spring months (more than 2.2 %/decade). By applying a defined threshold that includes the TOC monthly −2 σ, it is found that the maximum occurrence of low ozone events (LOEs) tends to be more frequent in the second half of year with about four-fifth of the observed LOEs (last summer, autumn, and early winter). During two cases of LOE, the tropopause height (TH) was uplifted ~2-4 km with temperature of 10 °C colder than the long-term mean, and the synoptic pattern was characterized by high-pressure systems in UTLS region. The extreme LOEs were consistent with the horizontal transport of ozone-poor air toward the Iranian plateau and vertical advection in UTLS region. The former mechanism plays a primary role in formation of extreme LOEs based on the observed TOC reductions during previous days over the source regions (Sahara desert and Himalaya region). Day-to-day variations of maximum UV index during LOEs show that by a decrease in TOC ~14 %, while the aerosol optical depth (AOD) in the cloudless condition reach their lowest rates (lower than 0.3), UV radiation exceeds very high and extreme levels in late winter and mid-spring, respectively. [ABSTRACT FROM AUTHOR]

Human and natural physical caused climate change can affect climate extremes, as well as maximum temperatures. The variations of the interannual and interdecadal hot temperatures have been studied between 1960 and 2012 (53 years) based on Abadan annual maximum temperatures (AAMT) data. The decadal analysis of the time variations of AAMT showed a positive and ascending trend in 60d, 70d and 90d, the neutral trend in 80d, and the descending trend in the last decade of the twentieth century. The positive time variations of AAMT in the 60d and 70d are too severe and more significant than that of other decades. The analysis of relationship between the absolute AAMT and the factors such as the global annual mean land-ocean temperature index (GAMLOTI), the annual concentration of atmospheric carbon dioxide (ACD), and the summer June-July-August (JJA) index of North Atlantic Oscillation (NAO) teleconnection pattern in AAMT showed that there is a significant correlation between AAMT and the mentioned factors. Thus, the relationship between the AAMT and the GAMLOTI is significant with a correlation coefficient of 0.602 at the significant level of 0.01. ACD had a negative significant correlation ( r = 0.60), and the JJA NAO index had a negative significant correlation ( r = −0.34) with AAMT. The results of multiple regression analysis showed that the overall effect of the GAMLOTI, the annual concentration of ACD, and the JJA NAO index on the temporal variability of AAMT during a 53-year period is 46.2 %. The relationship between the AAMT and the GAMLOTI and the annual concentration of ACD represents the effects of global warming on the variability of the AAMT. [ABSTRACT FROM AUTHOR]

Changes were made in the 5th author name, section 4.3.2 Spatial variations of cloud fraction based on latitude, section 4.3.4 Spatial variations of cloud fraction based on vegetation cover, section 5 Summary and conclusions, and Table 3. [ABSTRACT FROM AUTHOR]

In the current study, an α-lattice design was used to investigate 320 Iranian bread wheat cultivars and landraces under non-stressed and rain-fed conditions, according to phenological, morphological and physiological parameters. An artificial neural network (ANN) was trained to evaluate the relative importance of different drought tolerance indices (DTIs) using a multilayer perceptron model. Our findings suggest that the Iranian wheat germplasm harbors large genetic diversity for all the studied traits. Correlation analyses highlighted the important role of seed number per spike, thousand kernel weight, leaf greenness and canopy temperature in predicting grain yield under both non-stressed and rain-fed conditions. Moreover, correlations between stressed-yield (Ys) and yield index (YI, r = 1**), harmonic mean (HM, r = 0.94**), geometric mean productivity (GMP, r = 0.86**), and stress tolerance index (STI, r = 0.86**) were all large, which was further confirmed by the results of ANN and a principal component analysis. A hierarchical clustering, visualized using a heatmap plot, classified cultivars and landraces into four separate groups, where high-yielding and drought-tolerant genotypes clustered in the same group. The result of ANN indicated that MP and YI had the highest relative importance for screening compatible genotypes for well-watered and rain-fed conditions, respectively. Overall, the selection of genotypes according to agronomic and physiological traits in association with an appropriate DTI can identify favorable wheat genotypes in a field trial to breed for well-watered and water-limited environments. Furthermore, the ANN successfully evaluated the relative importance of different DTIs in wheat. [ABSTRACT FROM AUTHOR]

Station recording air temperature (Ta) has limited spatial coverage, especially in unpopulated areas. Since temperature can change greatly both spatially and temporally, stations data are often inadequate for meteorology and subsequently climatology studies. Time series of moderate-resolution imaging spectroradiometer (MODIS) land surface temperature (Ts) and normalized difference vegetation index (NDVI) products, combined with digital elevation model (DEM), albedo from Era-Interim and meteorological data from 2006 to 2015, were used to estimate daily mean air temperature over Iran. Geographically weighted regression was applied to compare univariate and multivariate model accuracy. In the first model, which only interfered with land surface temperature (LST), the results indicate a weak performance with coefficient of determination up to 91% and RMSE of 1.08 to 2.9 °C. The mean accuracy of a four-variable model (which used LST, elevation, slope, NDVI) slightly increased (6.6% of the univariate model accuracy) when compared to univariate model. RMSE dropped by 19% of the first model. By addition albedo in the third model, the coefficient of determination increased significantly. This increase was 32% of the univariate model and 23.75% of the 4-variable model accuracy. The statistical comparison between the three models revealed that there is significant improvement in air estimation by applying the geographically weighted regression (GWR) method with interfering LST, NDVI, elevation, slope, and albedo with mean absolute RMSE of 0.62 °C and mean absolute R2 of 0.99. In order to better illustrate the third model, t values were spatially mapped at 0.05 level. [ABSTRACT FROM AUTHOR]

Cloud types have a substantial influence on precipitation. This paper presents a study of the monthly variations of daytime different cloud types over Iran using data collected from Moderate-resolution Imaging Spectroradiometer (MODIS) aboard Terra during 2001-2015, MODIS aboard Aqua during 2002-2015, International Satellite Cloud Climatology Project (ISCCP) H-series cloud type data during 2001-2009 and precipitation rate associated with different cloud types using Tropical Rainfall Measuring Mission (TRMM) satellite products during 2001-2009. Different cloud types were determined using MODIS cloud optical thickness and cloud top pressure data based on ISCCP algorithm. The results showed that stratocumulus and cumulus clouds have maximum occurrence frequency over marine areas especially southern seas. The maximum frequency of nimbostratus and deep convective occurrence occurred over mountainous regions particularly at the time of Aqua overpass and cirrus and cirrostratus are observed over southeast of Iran during warm months due to monsoon system. Altostratus cloud is extended in each month except January, at the time of Terra overpass while nimbostratus is seen at the time of Aqua overpass during warm months in the study area. Cumulus and altocumulus clouds have shown remarkable frequency in all months especially over marine regions during warm and fall months. The higher value of precipitation rate is related to altostratus with a rate approximately 7 mm/h at the time of Terra overpass during April. Altostratus has the maximum recorded precipitation rate except in Nov., Dec., Sep., and Jan. at the time of Terra overpass, whereas the maximum precipitation rate is linked to nimbostratus cloud activity (up to 5 mm/h) except for March, April, and Sep. at the time of Aqua overpass. Deep convective (up to 1.32 mm/h), cirrostratus (up to 1.11 mm/h), and cirrus (0.02 mm/h) are observed only in warm months. The results were compared with ISCCP cloud types so that precipitation rate classified from low to high and Spearman rank correlation was calculated. The results showed good agreement between these two cloud type data; however, there were few notable difference between them. [ABSTRACT FROM AUTHOR]