جستجوی مقالات مرتبط با کلیدواژه « ردیابی » در نشریات گروه « علوم پایه »

Citrus psorosis virus is the causal agent of one of the most important viral citrus diseases in the world and has been detected from the citrus orchards in the east of Mazandaran province, IRAN. Because of the simultenious presence of various strains of this virus in infected citrus samples, molecular detection methods like PCR are not able to detect this virus with high accuaracy. In this research, we introduce a method for the precise detection of Citrus psorosis virus.

Detection and Identification of infected samples performed by triple antibody sandwich indirect-ELISA (TAS-ELISA) method and monoclonal antibody from symptomatic Thomson orange and Unshiu tangerine samples with suspicious symptoms to CPsV infection in Sari, Neka and Ghaemshahr districts of Mazandaran. Infection in samples tested by ELISA and confirmed by RT-PCR. Extraction of CPsV-dsRNA (Double-strand RNA) from infected samples was done by CF-11 column. Molecular hybridization performed by DIG labeled cDNA probe.

Exploring the electrophoretic pattern of dsRNA extracted from the CPsV infected citrus samples by using ELISA and RT-PCR methods, indicating the presence of CPsV genomes with the molecular weights of 920 bp and 2500 bp in infected samples. The presence of CPsV in the samples was also confirmed by using molecular hybridization and designed probe. 

The major advantages of the hybridization method relating to the dsRNA electrophoretic mobility is the simultenious detection of the all citrus psorosis virus strains within the infected citrus samples. This way can separate virus isolates.

Box tree moth Cydalima perspectalis (Walker, 1859) is one of the most important monophagous pests. This pest feeds on the leaves and bark of the Box trees stem and in some cases causes the death of the trees. In order to pest monitoring in 2017, 160 Delta pheromone traps and to investigate the possibility of pest control by pheromone traps in 2018, 600 funnel pheromone traps were installed in 450 hectare boxwood forest of Cheshmeh - Bulbul (Bandar-e-Gaz, Golestan Province). Also, 2 light traps and 4 pheromone- light sticky traps with photocell lamps were installed in the studied area. The results showed three flight peaks for box tree moth as well as the best time for chemical control and use the pheromone traps were determined. Our results also indicated the effectiveness of funnel-pheromone traps in reducing the damage of box tree moths. A significant difference between the number of boxwood moths trapped in pheromones with and without pheromones (P-value <0.05) was obvious, so that the combination of light traps with pheromones increases their efficiency.

In this research, satellite has been used for the purpose of identifying and finding the waters of the PersianGulf in the Sea of Oman.Finding the subsurface water exiting the PersianGulf through the cross of the Strait of Hormuz by identifying the temperature characteristics of Oman's surface water in the area where the presence of subsurface water in the Persian Gulf has been confirmed in previous studies can lead to finding the subsurface water.In this study, the sea surface temperature data of OSTIA for the studied basin, which is the Persian Gulf and a part of the Oman Sea(47 to59.45degrees of east and 22.60 to 32 degrees of north)was prepared.Then, according to the studies based on the73-year measurement data available in the region and identifying the temperature range of the surface water of the Oman Sea(22.20-23.00C) and the subsurface water of the Persian Gulf(16.00-22.20C)superimposed on each other, the satellite data were filtered. In order to filter the data and draw the figures, it was used coding in MATLAB environment.The results show that the water of the Persian Gulf can be transported to the middle parts of the Oman Sea, surface water (temperature 28.5 to 30 degrees of centigrade)in the cold season in the range of58.5to59degrees of east and in the warm season it advances towards the longitudes up to 59.5 degrees of east.As a result, the infiltration rate of Persian Gulf water in the Oman Sea in the warm season is half a degree of longitude more than the cold season.

The new insights into ocean-atmosphere-land synoptic studies, have led scientists to trace attractive atmospheric and oceanic phenomena. In this study, by using synoptic maps and some precipitation indices for Iran, we estimated the type and intensity of the extreme precipitation event in Dayyer Port synoptical station (27˚51ʹ34ʺN-51˚57ʹ52ʺ, ID: 40872) for 19March 2017. In order to identify oceanic sources of the water content for this precipitation event, air parcels were traced as lagrangian single particle trajectory by a hybrid model of HYSPLIT which is run backward interactively on the web site, during 9-days by the start of maximum rainfall, locatacted at Dayyer port station. Accordingly, we plotted pattern of the average moisture transfer paths on 800-550 hPa atmospheric levels. The field climate data (including wind speed and direction, relative humidity and precipitation) with 6-hour time steps and spatial resolution of 2.5˚×2.5˚(longitude and latitude), entered into the model from the reanalysis global data archive of the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR). Consequently, by assessment of the meteorological maps and data and by using a precipitation index of R10mm, we found that this precipitation event (19th March 2017) defined as a heavy precipitation day. Finally, the simulation outputs clearly showed that the water contents of this rainfall system (19th March 2017) originates from two source locations of the north area of Indian Ocean (Arabian Sea), and also the east part of Atlantic Ocean. In addition, the results illustrated that during the occurrence of this precipitation event, an extra-tropical cyclone was active on the studied area.

Dust phenomenon is one of the most harmful natural disasters in low rainfall regions of the world, especially in Iran, which brings many environmental problems in these areas. It is also one of the environmental challenges in the Middle East and Iran in recent years. This phenomenon has become one of the main problems in arid and semi-arid regions today, which has adverse social, economic and environmental effects and it can be said with certainty that one of the environmental hazards in arid and semi-arid regions of the world are dust storms, This environmental event is considered as a climatic hazard and causes or exacerbates cardiovascular diseases, respiratory diseases and many allergies in the human body, Large amounts of dust are transported every year from the deserts of North Africa, the Arabian Peninsula, Iraq and Syria to different parts of Iran. Depending on global warming and wind speeds such as Harmatan and other strong local winds, these dusts are drawn to an altitude of 3,000 meters and above and are transferred to the areas in front of these systems by entering the wind systems of the Mediterranean and North Africa. Dust is one of the most common atmospheric phenomena and one of the biggest environmental problems in arid and semi-arid regions, which has devastating effects on the inhabitants of these areas every year. In recent years, pollution caused by dust particles has become one of the environmental problems, especially in developing countries. Considering that Iran is also located in the arid and semi-arid region of the world and a large area of the country is considered as an arid and semi-arid region, it is necessary to study this phenomenon.

The main purpose of this study is to explain the causes of occurrence and routing of dust storm springs in Kermanshah in the three-day period from October 26 to 28, 2018. In the first stage, using meteorological data, the days associated with the dust storm were determined. In the second stage, for synoptic analysis of the causes of the storm, from the ECMWF European Center for Medium-Term Forecasting Database with a resolution of 0.125 degrees, including geopotential height of 500 hPa, omega of 700 hp, sea level pressure SLP, components Orbital and meridional wind at the level of 300 hPa, special humidity at the level of 700 hPa due to higher resolution and satellite data of soil moisture to a depth of 10 cm were used in the study area. Using the above data in using GRADS software; Wind patterns and synoptic systems effective in transporting fine dust to Kermanshah were drawn. In the third stage, using the HYSPLIT model, dust particles were detected at three levels of 200, 1000 and 1500 meters above the ground at a time interval of 6 to 48 hours before the occurrence of dust. WRF-CHEM numerical weather simulation model was used to prepare numerical maps of particle concentration distribution and dust storm path to western Iran. In the present study, using version 3,6,1 of the WRF-CHEM paired model, simulations were performed for 3 days from 26 to 28 October 2018 using GFS analysis data for initial and boundary conditions. In this implementation, the advanced MADE-SORGAM schema was used as the emission pattern of airborne particles, which in turn is based on the regional model of airborne particles. In MADE design, airborne particles in three models with a diameter of less than 0.1 μm, cumulative with a diameter between 0.1 to 2 μm and large with a diameter greater than 2 μm with a log-normal distribution were included in the air quality simulation process. In the last step, MODIS images were used to determine the sources of dust diffusion to the west of Iran, and also by using the optical depth detection index of AOD aerosol, the numerical distribution map of dust aerosols in the atmosphere was obtained.

According to the results of the analysis of synoptic maps, in fact, the main cause of the dust wave phenomenon from 26 to 28 October 2018 in Kermanshah, in addition to the instability caused by low surface heat pressures, Saudi high-pressure movements that cause currents to converge towards Have become western. Deployment of a low pressure section in the middle levels of the atmosphere is well visible in this event, so that despite the instability in the middle level of the atmosphere, lack of sufficient moisture in the systems transferred to the west of the country, currents flowing through the deserts of Iraq and Syria. Sufficient both in the surface and in the depth of the soil inside the country and in neighboring countries has led to the formation of a dust spring and its transfer to the study area. Also, the examination of the tracking maps obtained from HYSPLIT shows that two general paths for the transfer of dust to the study area can be identified: 1- The northwest-southeast route, which passes through dust cores formed in the deserts of Iraq and Syria, transports dust to the western half of Iran; This route can be considered as the entry of dust into the area at an altitude of 1000 to 1500 meters. 2- The southwest-west route of Iran and the city of Kermanshah, which at an altitude of 200 to 1000 meters, which is the main source of dust on October 27 and 28, is the source of particles in this route Kuwait, northern Saudi Arabia and part of Iraq. Examination of the particle path shows that these particles were first transported to higher levels by low pressure systems located in the area and then pulled to the ground in two paths. The soil moisture map also shows a severe lack of moisture up to a depth of 10 cm in the soil that at the same time with the passage of unstable systems and western currents over the areas, subsoil particles are easily separated from the ground and transferred to the study area. By simulating dust storms from the west wind by the WRF-chem model, it showed that the main source of dust is located in the western and central deserts of Iraq, Syria and northern Saudi Arabia.

Due to the increase of this phenomenon, current study focuses on the climate and statistical analysis of dust storms in Iran during 2015.

Hourly data of meteorological code are used in this study. The software WRPLOT VIEW was utilized to plot wind rose. For Synoptic analysis of the storm, data information of middle and upper atmospheres including sea-level pressure data and geopotential height of 500hP surface was received from NCEP/NCAR database, and their circulation patterns were obtained. In order to determine the trajectories of dust storms, the air parcel tracking model HYSPLIT was applied.

The maximum dust events were occurred in Zabol during 2015. Highest wind speed and severest loss of vision were observed at Zabol station on 6 July. The masses of dust were entered to Arak and Fasa from the west and northwest of Iraq and to Zabol from Afghanistan. Records of sea-level and middle-atmosphere circulation database on 21 July 2015, that showed the severest loss of vision in Fasa, revealed the presence of a low-height system over Russia and a high pressure system over the north black sea. A low pressure system was observed over Pakistan which its tabs were extended to the east and south regions of Iran. 

Discussion and Conclusion:

Blowing dust in Zabol can have a local dust source. The greatest dust in suspension events in Arak & Fasa with lower wind speed along. Northeasterly winds can cause of Sistan 120-day wind during the cold time of year that its impact will be greater in Zabol. On the day that severest loss of vision observed, most part of the country affected by tabs of high pressure located on the west in Iraq, that have been reached to the center of Iran with its easterly side.

​One of the main challenges in the treatment of genetic disorders, such as cancer, is of drug delivery systems and their inability to monitor and track delivered drug to the targeted site. Therefore, the design of novel with dual capabilities of nuclear drug delivery and tracking into a research priority for this field’s The aim of this study is to design based on both non-cytotoxic quantum dots and chimeric peptides, with dual tracking and delivering small genetic agents into the nucleus. The GQDs with green emission color were synthesized by Hummer’s and methods and characterized by UV-Vis, photoluminescence (PL), Raman spectroscopies, and scanning electron microscopy (SEM). conjugated with MPG-2H1 chimeric peptides through noncovalent interactions. Following conjugation step, the ζ-potential of the complex increased (From -38.6 to -11.1 in complex1, -9.6 in complex2 and -5.74 in complex3). The conjugation was confirmed by native acrylamide gel retardation assay. The of the GQDs was investigated by MTT assay and finally, was carried out. The results showed that MPG-2H1/ GQD complexes can enter cells; however, free-GQDs didn’t enter the cells significantly.

Dust storms, one type of dust event, are in most cases the result of turbulent winds, including convective haboobs, which raise large quantities of dust from desert surfaces and reduce visibility to less than 1 km. This dust reaches concentrations in excess of 6000 mg m3 in severe events. The major dust source regions are areas of arid and hyper-arid, with mean annual rainfalls of less than 100 mm. The temporal and spatial investigation of dust storms shows the interference of various factors in their occurrence and expansion. These factors is divided into two groups; environmental and human parameters. The climatic (such as low rainfalls, high evaporation, intense wind, drought and atmospheric general circulation) and geological (for example lithology such as Quarts, Clay, Silicate and feldspar) factors are natural parameters, and factors such as over grassing and crop production, wastage of vegetation, increasing growth of population, battle and political problems are human parameters. Much of the current interest in dust storms relates to their possible role in the systems and subsystems of Earth. Dust loadings may affect air temperatures through the absorption and scattering of solar radiation, may affect cloud formation, and convectional activity, influence sulphur and carbon dioxide levels in the atmosphere, and influence geo-chemistry cycle, soil evolution and desertification. Dust storms are one of the destructive climatic phenomena which are affected by various climatic elements such as pressure, precipitation, wind, temperature and evaporation. These phenomena impose much damages to human health, industrial and agricultural installation, population centers and communication ways. The recognition of source regions, creation and expansion style of dust storms and their relation with atmospheric circulation patterns are fundamental factors in reduction of their damages. In recent decades, trend of dust storms has increased in Iran, specially west and southwest areas. This factor is raised the necessity of dust study in these areas more than before. Frequency and intensity of dust storms in west and south west parts of Iran has made this phenomenon one of the most principal environmental hazards in these regions. According to the extent of dust storms and their vast effects on health, economy, environment and agriculture and their increasing trend has drew the attention of many researchers. The recent study is composed of data analysis of dust storm by Iran Meteorological Organization Earth Database, synoptic analysis of weather and climate patterns causing and transmitting dust using middle and upper atmosphere data in Shiraz, Fasa and Bushehr stations and tracking wind packages carrying dust particles using HYSPLIT model by forward and backward methods.

In the research, environmental and circulatory databases were used to be analyzed the synoptic systems of Comprehensive Dust Storms in the South and Center of Iran. At first, the number of dust days was determined using climatic data of more than 30 synoptic station in a 9-year period, from 2002 to 2009. Then, their circulation patterns were identified and plotted. Also, the circulation patterns of extreme dust days was identified and plotted in the study area. Though, meteorological data, the middle and upper atmosphere data such as the sea level pressure data, level of 500 hPa geo-potential height, wind direction, vertical velocity, surface temperature and the subtropical wind profiles were received from 100-1000 hPa height from NCEP/NCAR database and were drawn for 0-80 longitude and 10-70 latitude using GRADS software. Then, visibility, wind direction and velocity, relative humidity and precipitation were extracted for each day. WRPLOT VIEW VERSION 5.3 software was used for wind rose drawing by wind storms causing direction and speed. HYSPLIT model was used in order to recognize the origin of dust storms and wind flow routing in Shiraz, Fasa and Bushehr stations.

In recent decades, the global effectiveness of dust storms has become increasingly apparent, so that, major advances have occurred in sources, transport paths and their many impacts both on humans and the environment, their frequency at different time scales. Earth database investigations shows that the year 2008 has one of the most extreme dust storms in terms of visibility reduce and durability of dust storm days in the study period that 2008 June 10 is the most extreme dust storm day with visibility of less than 500 meter in the stations. The mentioned dust storm as one of the most intense dust storms of the recent years can help having a good recognition of atmosphere patterns causing this phenomenon and routing winds transmitting aerosols. The results of the middle and upper atmospheric circulation base shows that west winds occurred in 2008 June 10 with a low pressure center in the East of Iran and high pressure in the North of Africa (Figures 1 & 2). The condition is caused the entrance of dust to the study region. The isothermal map of sea surface represents the ascendancy of 50 degrees curve on the center of Iran and isothermal map of 42.5 degrees on the East Saudi Arabia. Besides, the curves of 40 degrees have dominated on Iraq and Syria which causes temperature increase and drought air in the region. Omega map of sea surface at 2008 June 10 indicates the -0.1 conture in Central regions of Iran which shows the downward air flow in the area. Also, the central core of the upward flow, with 0.2 contour are dominate in the North of Saudi Arabia, Iraq and Syria, which illustrate an air mass with ascending movement in these areas. Patterns related to humidity represent relative humidity of 10% in Iran. Also, specific humidity is very low and is equal to 0.004 which represent minimum rates of humidity and very high drought causing or increasing dust storms in the studied day. The results of wind flow routing by HYSPLIT model showed that the origin of dust storm mass had been North West of Iraq and east of Syria which had entered Iran with a north west-south east direction (figures 3 & 4).

The study of circulation patterns transferring dust storms in the South and Center of Iran have abundant importance. For example, the west region of Iran isn’t a source of dust because of natural characteristics such as mountainous areas, high rainfalls and dense vegetation. But, dust storms of this region are non-local. This region is the transport route of climatic systems into Iran, and accepts the most effectiveness from these systems. According to source regions of Iran dust storms which are hyper-arid lands of Iraq, Saudi Arabia, Syria and North Africa, this study is a connective step between large scale circulation patterns and temporal and spatial activities of dust storms in the South and Center of Iran. According to the results of this study which has examined the relationship between large scale synoptic patterns and variety of space-time dust storm activities in Iran using synoptic maps of sea level pressure circulation patterns, 500 hPa geo-potential height, wind direction data, vertical velocity, surface temperature with geo data of dust storms in the studied stations and wind flow routing model, it can be concluded that dynamic models can be presented by consensus of various specialists for this destructive environmental phenomenon. Although, using the capability of satellite imagery and dust storm investigating using them can be of great importance for future studies. In general, the results of this research shows that wind flow routing model and atmosphere studies have the suitable capability for recognition and monitoring of dust storm path.

In this paper, the method of identifying of the similar solar flux tubes from image sequence EUVI/STEREO is presented. Using the oriented coronal curved loop tracing, the loops of an image are labeled. Based on local maxima intensities, the width of loops is determined. The Zernike moments of each loop are calculated and fed to probabilistic network classifier. Also, 588 loops from STEREO are studied.