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Background: Since early 2020, Coronavirus 2019 (COVID-19) has posed a public health risk due to serious acute respiratory syndrome. The aim of our study was to determine surface circulation of SARS-CoV-2 RNA in Asadabad Hospital wards. Methods: Fifty swab samples were obtained from the hospital wards. The real-time test was carried out using primer/probe sets that were complementary to targets on the SARS CoV genome. Results: The injection room had the highest contamination rate, while the other hospital wards were free of COVID- 19 contamination. Conclusions: Overall, we found that COVID-19 contaminated narrowly the surfaces in hospital wards. These findings can be used to improve safety procedures. [ABSTRACT FROM AUTHOR]

The 1990 Rudbar earthquake (Mw 7.3) broke along three right‐stepping segments of the left‐lateral Rudbar fault, in the western Alborz mountains (Iran), producing ∼80 km of surface rupture. Previously reported horizontal (∼60 cm) field offsets were surprisingly low, and the vertical (∼95 cm) unexpected, given the relatively large moment release, shallow source depth, vertical fault geometry, and left‐lateral rake. We characterize the surface displacement from optical image correlation of satellite and aerial images. A maximum displacement of ∼6.5 m is observed in the eastern part of the rupture consistent with both a sharp pulse in the moment release rate ∼10 s after the rupture initiation, and the macroseismic isoseismal curves. We find ∼2.2 m mean surface slip, larger than field measurements, but consistent with empirical scaling laws based upon the seismological moment release. Estimates of fault zone width based on correlation of 1 m resolution aerial photos (and corrected for smoothing bias) are <200 m; these values increase artificially with lower resolution imagery, which is more affected by smoothing bias. The large mismatch between field and correlation displacements suggests the Rudbar earthquake probably featured significant off‐fault deformation, consistent with its low structural maturity. Finally, we document a surface rupture along a structural continuation of the Kabateh segment, east of the Sefid Rud river. Slip along this segment (1–2 m), is less than the neighboring Zard Geli segment (1.5–6 m). The two faults converge at Sefid Rud, which appears to represent a major structural feature controlling fault segmentation in this region.Plain Language Summary: The 1990 (Mw 7.3) Rudbar earthquake was one of the most destructive earthquakes to have affected Iran in recent history. However, despite the relatively large size of the earthquake, field surveys revealed surprisingly small (<1 m) left‐lateral offsets. We resolve this long‐standing problem using new optical correlation techniques, which allow us to fully document the earthquake surface displacement. Left‐lateral offsets reached up to 5‐6 m along the Zard Geli fault segment, while new surface ruptures are reported along a failed branch of the rupture east of the Sefid Rud river valley. Our results indicate that slip was relatively continuous between various fault segments, with slip becoming distributed in the fault linkage zones. We find that OFD is unusually high, and appears to vary as a function of the fault geometric roughness. This study highlights the power of optical image correlation for revisiting past earthquakes and providing valuable new constraints on surface ruptures in general. With this approach, we may thus expand the catalog of earthquakes that have robust measurements of on‐ vs off‐fault slip, which will be essential for characterizing the parameters that control the localization of coseismic slip, and how we engineer for future surface rupturing earthquakes.Key Points: We characterize the surface displacement field associated with the 1990 Rudbar earthquake using new optical image correlation techniquesWe find the average surface slip ∼2.2 m, with a maximum displacement of ∼6.5 m along Zard Geli eastern part of the fault ruptureWe find that off‐fault deformation is unusually high, and appears to vary as a function of the fault geometric roughness [ABSTRACT FROM AUTHOR]

Varying estimates of both present‐day strain accumulation and long‐term slip rate on the Doruneh left‐lateral strike‐slip fault, NE Iran, have led to suggestions that it exhibits large along‐strike and/or temporal changes in activity. In this study, we make and compare estimates of slip rate measured using both geodesy and geomorphology, and spanning time periods ranging from decadal to 100 ka. To image the present‐day accumulation of strain, we process 7 years (2003–2010) of data from six ENVISAT tracks covering the fault, with interferograms produced for 400‐km‐long strips of data to image the long‐wavelength signals associated with interseismic strain accumulation across the locked fault. Our analysis shows that less than 4 mm/yr—and likely only 1–3 mm/yr—of slip accumulates across the fault. Using high‐resolution optical satellite imagery, we make reconstructions of displacement across six alluvial fans whose surfaces cross the fault, in four separate river catchments. We determine the ages of these fans using infra‐red‐stimulated luminescence dating combined with U‐series dating of pedogenic carbonates. The six fans vary in age from ∼10– to 100 kyr, and a regression line fitted to four of these yields a slip rate of 2.5 ± 0.3 mm/yr. We conclude that within the uncertainty of our measurements, the slip rate has remained constant over the last ∼100 ka and is representative of the strain accumulation at the present‐day. The slip rate that we measure is consistent with the E‐W left‐lateral Doruneh fault accommodating N‐S right‐lateral faulting by "bookshelf" faulting, with clockwise rotation about a vertical axis. Key Points: We compare present‐day strain accumulation and late Quaternary slip on the Doruneh fault, IranWe conclude that the fault has slipped at a constant rate of 2.5 ± 0.3 mm/yr throughout the last ∼100 ka [ABSTRACT FROM AUTHOR]

Cucumber is one of the main vegetables in Iranian food basket. A wide range of pesticides are used for crops protection during the cultivation of vegetables such as cucumber due to heavy pest infestation. Analysis of pesticide residues in food and other environmental commodities have become essential requirement for consumers, producers, and food quality control authorities. This study was aimed at determination of pesticides residues in cucumber as a main vegetable in Iranian food basket. A reliable, rapid and accurate method based on spiked calibration curves and modified QuEChERS sample preparation was developed for determination of 12 pesticide residues in cucumber by gas chromatography-mass spectrometry (GC/MS). The use of spiked calibration standards for constructing the calibration curve substantially reduced adverse matrix-related effects. The recovery of pesticides at 5 concentration levels (n = 3) was in the range of 80.6-112.3. The method was proved to be repeatable with RSD lower than 20%. The limits of detection and quantification for all pesticides were <10 ng/g and <25 ng/g, respectively. The developed method was used for simultaneous determination of the selected pesticides in 60 greenhouse and garden cucumber samples. Among the 60 analyzed samples, 41.7% of them were contaminated with pesticide residues which 31.7% of samples had pesticide residues lower than maximum residue limit and 10% of samples had residue higher than maximum residue limit. [ABSTRACT FROM AUTHOR]

• Joint well-InSAR data for estimating storage and head in aquifer of large subsidence. • Spatial distribution map of a confined aquifer from InSAR. • Long-term and seasonal vertical land deformation maps in the Gorgan Plain by InSAR. • LOS land deformation is mostly related to the vertical components rather horizontal. In this study, Interferometric Synthetic Aperture Radar (InSAR) is applied to analyze the land deformation across the Gorgan Plain, Iran, where recent droughts and over-exploitation of groundwater leading to widespread subsidence. Having significant long-term and seasonal signals in head measurements, analysis of TOPS S1 month-scaled images from October 2014 to October 2016 exhibits significant inelastic (70 mm/yr on average) and seasonal elastic (ranging from about 20 to 132 mm) vertical land deformation over the Gorgan confined aquifer system (GCAS), according to the decomposed vertical displacement map. The investigations indicate that these significant deformations are due to both severe head decline (up to ~2 m/yr) and the presence of thick aquitards intervening aquifers. To obtain elastic land deformation (totally recoverable) and static head components, the inelastic (partially recoverable) and long-term head decline trends are removed by lines fitted to the land deformation and head time series, respectively. Having a high cross-correlation coefficient between the seasonal components of head and land deformation time series (ranging from 0.60 to 0.93; ~0.78 on average), we use a joint well-InSAR data analysis to estimate bulk aquifer parameters of the elastic skeletal storativity (0.0035 to 0.0142 ; 0.0085 on average), specific storage (1.54 × 10 - 5 to 7.68 × 10 - 5 m - 1 ; 4.35 × 10 - 5 m - 1 on average), and compressibility (1.50 × 10 - 10 to 7.40 × 10 - 10 N / m 2 ; 4.20 × 10 - 10 N / m 2 on average) at 14 piezometer locations. InSAR-derived aquifer storage properties are reasonably correlated with the hydrogeological setting of GCAS. Moreover, the elastic land deformation data are acceptably transformed to head fluctuations at 14 piezometers and several arbitrary point locations. It is observed that the heads reconstructed from InSAR and measured in piezometers are consistent over a broad portion of GCAS. Seasonal elastic land deformations occurred between wet and dry seasons in 2015 are also used to map the confining degree across GCAS. The higher confining degree has been observed in those areas of higher subsidence signatures, implying that the subsidence potential in confined aquifers is higher than that of unconfined aquifers. In this study, we have demonstrated more benefits of the InSAR observations in estimating aquifer storage properties and predicting head in confined aquifers of significant subsidence signatures with better temporal and spatial resolution than that can be retrieved from hydrogeological data alone. [ABSTRACT FROM AUTHOR]