Deterministic seismic hazard assessment for Sultanate of Oman

The Sultanate of Oman forms the southeastern part of the Arabian plate, which is surrounded by relatively high active tectonic zones. Studies of seismic risk assessment in Oman have been an important on-going socioeconomic concern. Using the results of the seismic hazard assessment to improve building design and construction is an effective way to reduce the seismic risk. In the current study, seismic hazard assessment for the Sultanate of Oman is performed through the deterministic approach with particular attention on the uncertainty analysis applying a recently developed method. The input data set contains a defined seismotectonic model consisting of 26 seismic zones, maximum magnitudes, and 6 alternative ground motion prediction equations that were used in four different tectonic environments: obduction zone earthquake (Zagros fold thrust belt), subduction zone earthquakes (Makran subduction zones), normal and strike-slip transform earthquakes (Owen and Gulf of Aden zones), and stable craton seismicity (Arabian stable craton). This input data set yielded a total of 76 scenarios at each point of interest. A 10 % probability that any of the 76 scenarios may exceed the largest median ground acceleration is selected. The deterministic seismic hazards in terms of PGA, 5 % damped spectral acceleration at 0.1, 0.2, 1.0 and 2.0 s are performed at 254 selected points. The ground motion was calculated at the 50th and 84th percentile levels for selected probability of exceeding the median value. The largest ground motion in the Sultanate of Oman is observed in the northeastern part of the country.Oman Ministerial Cabinet (Project 22409017

Probabilistic seismic hazard maps for the sultanate of Oman

This study presents the results of the first probabilistic seismic hazard assessment (PSHA) in the framework of logic tree for Oman. The earthquake catalogue was homogenized, declustered, and used to define seismotectonic source model that characterizes the seismicity of Oman. Two seismic source models were used in the current study; the first consists of 26 seismic source zones, while the second is expressing the alternative view that seismicity is uniform along the entire Makran and Zagros zones. The recurrence parameters for all the seismogenic zones were determined using the doubly bounded exponential distribution except the zones of Makran, which were modelled using the characteristic distribution. Maximum earthquakes were determined and the horizontal ground accelerations in terms of geometric mean were calculated using ground-motion prediction relationships developed based upon seismic data obtained from active tectonic environments similar to those surrounding Oman. The alternative seismotectonic source models, maximum magnitude, and ground-motion prediction relationships were weighted and used to account for the epistemic uncertainty. Hazard maps at rock sites were produced for 5 % damped spectral acceleration (SA) values at 0.1, 0.2, 0.3, 1.0 and 2.0 s spectral periods as well as peak ground acceleration (PGA) for return periods of 475 and 2,475 years. The highest hazard is found in Khasab City with maximum SA at 0.2 s spectral period reaching 243 and 397 cm/s[superscript 2] for return periods 475 and 2,475 years, respectively. The sensitivity analysis reveals that the choice of seismic source model and the ground-motion prediction equation influences the results most.Oman Ministerial Cabinet (project number 22409017

Seismic microzonation for Muscat region, Sultanate of Oman

Site characterization was carried out for Muscat region using the ambient noise measurements applying the horizontal-to-vertical spectral ratio (HVSR) technique and using active seismic survey utilizing the multichannel analysis of surface waves (MASW) of survey data. Microtremors measurements were carried out at 459 sites using short-period sensors. This extensive survey allowed the fundamental resonance frequency of the soft soil to be mapped and areas prone to site amplification to be identified. The results indicate a progressive decrease in the fundamental resonance frequencies from the southern and eastern parts, where the bedrock outcrops, toward the northern coast where a thickness of sedimentary cover is present. Shear wave velocity (Vs) was evaluated using the 2-D MASW at carefully selected 99 representative sites in Muscat. These 99 sites were investigated with survey lines of 52 m length. 1-D and interpolated 2-D profiles were generated up to a depth range 20–40 m. The vertical Vs soundings were used in the SHAKE91 software in combination with suitable seismic input strong motion records to obtain the soil effect. Most of the study area has amplification values less than 2.0 for all the considered spectral periods. The estimated fundamental frequencies obtained using the H/V spectral ratio method and using SHAKE91 are found to be in a relatively good agreement. Maps of spectral amplification, earthquake characteristics on the ground surface for peak ground and spectral accelerations at 0.1, 0.2, 0.3, 1.0, and 2.0 s, for 475 years return period are produced. The surface ground motion maps show that the hazard level is moderate with expected PGA in the range 0.059–0.145 g for 475 years return period.Oman Ministerial Cabinet (project # 22409017

Traditional knowledge of wild edible plants used in Palestine (Northern West Bank): A comparative study

<p>Abstract</p> <p>Background</p> <p>A comparative food ethnobotanical study was carried out in fifteen local communities distributed in five districts in the Palestinian Authority, PA (northern West Bank), six of which were located in Nablus, two in Jenin, two in Salfit, three in Qalqilia, and two in Tulkarm. These are among the areas in the PA whose rural inhabitants primarily subsisted on agriculture and therefore still preserve the traditional knowledge on wild edible plants.</p> <p>Methods</p> <p>Data on the use of wild edible plants were collected for one-year period, through informed consent semi-structured interviews with 190 local informants. A semi-quantitative approach was used to document use diversity, and relative importance of each species.</p> <p>Results and discussion</p> <p>The study recorded 100 wild edible plant species, seventy six of which were mentioned by three informants and above and were distributed across 70 genera and 26 families. The most significant species include <it>Majorana syriaca, Foeniculum vulgare, Malvasylvestris</it>, <it>Salvia fruticosa, Cyclamen persicum, Micromeria fruticosa, Arum palaestinum, Trigonella foenum-graecum</it>, <it>Gundelia tournefortii</it>, and <it>Matricaria aurea</it>. All the ten species with the highest mean cultural importance values (mCI), were cited in all five areas. Moreover, most were important in every region. A common cultural background may explain these similarities. One taxon (<it>Majoranasyriaca</it>) in particular was found to be among the most quoted species in almost all areas surveyed. CI values, as a measure of traditional botanical knowledge, for edible species in relatively remote and isolated areas (Qalqilia, and Salfit) were generally higher than for the same species in other areas. This can be attributed to the fact that local knowledge of wild edible plants and plant gathering are more spread in remote or isolated areas.</p> <p>Conclusion</p> <p>Gathering, processing and consuming wild edible plants are still practiced in all the studied Palestinian areas. About 26 % (26/100) of the recorded wild botanicals including the most quoted and with highest mCI values, are currently gathered and utilized in all the areas, demonstrating that there are ethnobotanical contact points among the various Palestinian regions. The habit of using wild edible plants is still alive in the PA, but is disappearing. Therefore, the recording, preserving, and infusing of this knowledge to future generations is pressing and fundamental.</p

Improved functionalization of oleic acid-coated iron oxide nanoparticles for biomedical applications

Superparamagnetic iron oxide nanoparticles can providemultiple benefits for biomedical applications in aqueous environments such asmagnetic separation or magnetic resonance imaging. To increase the colloidal stability and allow subsequent reactions, the introduction of hydrophilic functional groups onto the particles’ surface is essential. During this process, the original coating is exchanged by preferably covalently bonded ligands such as trialkoxysilanes. The duration of the silane exchange reaction, which commonly takes more than 24 h, is an important drawback for this approach. In this paper, we present a novel method, which introduces ultrasonication as an energy source to dramatically accelerate this process, resulting in high-quality waterdispersible nanoparticles around 10 nmin size. To prove the generic character, different functional groups were introduced on the surface including polyethylene glycol chains, carboxylic acid, amine, and thiol groups. Their colloidal stability in various aqueous buffer solutions as well as human plasma and serum was investigated to allow implementation in biomedical and sensing applications.status: publishe

Seroprevalence of Trypanosoma evansi infections among dromedary camels (Camelus dromedaries) in North Al-Sharqiya governorate, Sultanate of Oman

Trypanosoma evansi is a well-known hemoprotozoa that infects diverse domestic and wild animals worldwide and caused devastating disease called surra. This research aimed to investigate the seroprevalence of Trypanosoma evansi and its associated risk factors in dromedary camels in North Al-Sharqiya governorate in the Sultanate of Oman.  A total of 4364 serum samples was collected from three willayat in north governorates of Sultanate of Oman; Ibra (926, 21.2%), Qabil (1119, 25.6%) and Bidiyah (2319, 53.1%). Samples were examined for the presence of antibodies against T. evansi using card agglutination test (CATT/T. evansi). Binary logistic regression was used to study the association of T. evansi seroprevalence and risk factors such as location, gender, purpose and age of camels. The overall seroprevalence of T. evansi detected by CATT/T. evansi test was 38% (1659/4364, CI: 36.6-39.5%). There was a significant difference (p=0.001) between location and T. evansi seroprevalence, whereas highest seroprevalence was found in Ibra (49.9%, CI: 46.7-53.1%) followed by Bidiyah (35%, CI: 33-36.9%) and Qabil (34.5%, CI: 31.8-37%). Camels from Ibra were almost two times more likely to have circulating antibodies of T. evansi than camels from Bidiyah (OR=1.89, CI: 1.591-2.168). Also, the results showed a significant difference between seroprevalence and sex (p=0.023), whereas the age of camels was not (p&gt;0.05). To our knowledge, this is the first research that indicated that T. evansi antibodies were circulating among camels in Oman, and further research needs to be tackled to study the molecular characterization of T. evansi and its prevalence in other animal species. Furthermore, cross-sectional studies of T. evansi from different regions in Oman warrant further investigation