Crustal scattering and intrinsic attenuation of S-waves in southern Aegean derived using envelope inversion

2020 ◽  
Author(s):  
Pratul Ranjan ◽  
Konstantinos I. Konstantinou
Keyword(s):  
Eastern Mediterranean ◽  
Eastern Mediterranean Region ◽  
Eurasian Plate ◽  
Linear Inversion ◽  
African Plate ◽  
Frequency Bands ◽  
S Waves ◽  
High Q ◽  
Intrinsic Attenuation ◽  
Station Pair

<p>Southern Aegean is the major part of the Eurasian plate overriding the subduction of African plate in eastern Mediterranean region. In this study, shallow depth (< 40 km) events recorded by temporary and permanent seismic networks in southern Aegean are used to study the crustal scattering attenuation (Q<sub>s</sub><sup>-1</sup>) and intrinsic attenuation (Q<sub>i</sub><sup>-1</sup>) of S-waves. The 3 component S-waveforms are filtered in 1-2, 2-4, 4-8, and 8-16 Hz bands and envelopes are calculated by smoothing the root mean square of individual components. The envelopes are modeled using the approximate analytical solution of 3D isotropic radiative transfer equation. The fitting is performed using grid search approach to obtain Q<sub>s</sub><sup>-1 </sup>and then linear inversion is used to calculate Q<sub>i</sub><sup>-1 </sup>for each source station pair. The results obtained from each source-station pair are assigned to an ellipsoid region and robust mean technique is used to map the results in each 0.20<sup>o </sup>x 0.20<sup>o</sup> bin. The final results indicate consistently high Q<sub>s</sub><sup>-1</sup> in western Crete in all 4 frequency bands. Also, high Q<sub>s</sub><sup>-1</sup> is observed in western Peloponnese in 1-2 and 2-4 Hz frequency bands. High Q<sub>i</sub><sup>-1</sup> is observed along the volcanic arc in all 4 frequency bands. Our results compare well with the recent S-wave scattering study in the region. They are also consistent with the geodynamics of southern Aegean subduction zone. Our study provides useful insight about the attenuation in the southern Aegean crust which has implications for ground motion and seismic hazard.</p>

scholarly journals The eastern Mediterranean phosphorite giants: An interplay between tectonics and upwelling

GeoArabia ◽  
2013 ◽  
Vol 18 (2) ◽  
pp. 67-94 ◽  
Author(s):  
Abdulkader M. Abed
Keyword(s):  
Eastern Mediterranean ◽  
Eastern Mediterranean Region ◽  
Uranium Content ◽  
Late Eocene ◽  
Arabian Plate ◽  
African Plate ◽  
Northwestern Saudi Arabia ◽  
The North ◽  
Platform Margin ◽  
Tethys Ocean

ABSTRACT About 20 billion tonnes of world-class, high-grade phosphorite resources occur in a small area of the eastern Mediterranean region, including Jordan, northern Negev (Palestine), northwestern Saudi Arabia, western Iraq, and southeastern Syria. Major deposits were formed during Campanian to Eocene times and contribute significantly to the economic development of these countries, particularly Jordan and Syria. The phosphorite deposits consist mainly of reworked granular material. The phosphate particles are peloids, such as pellets, intraclasts, nodules, coated grains and coprolites, and vertebrate fragments (bone and teeth). The phosphorite sequences are associated with extensive bedded chert, porcelanite, and organic-rich marls. The main phosphate mineral is francolite, a carbonate-rich variety of fluorapatite that has a relatively enhanced uranium content as a result of substitution for calcium in its crystal structure. Two factors are deemed responsible for the deposition of the phosphorites and their associated chert, porcelanite, and marl within this relatively restricted area. The first was a compressional event associated with the initial collision of the oceanic forefront of the Afro-Arabian Plate with the subduction trench of Eurasia that began in Turonian times and continued into the Eocene. This event resulted in gentle folding that produced the Syrian Arc, the Ha’il, Rutba, and Sirhan paleohighs and the Ga’ara Dome, which were loci for the deposition of phosphorites. The second factor was the obstruction and consequent upwelling of oceanic currents by these tectonic highs, enhanced by winds blowing from east to west along the southern platform margin of the Neo-Tethys Ocean. The intense upwelling was associated with the Tethyan Circumglobal Current that flowed along the Afro-Arabian platform on the southern margin of the Neo-Tethys Ocean. In contrast, relatively minor phosphorite deposition took place to the north in southern Europe. The upwelling spread cold, nutrient-rich oceanic water from the deep Neo-Tethys Ocean to the surface, thereby enhancing bioproductivity to produce organic-rich sediments. The subsequent authigenesis of phosphorites, their diagenesis and the reworking and winnowing of the phosphorite-rich sediments, concentrated the materials into economic deposits. Phosphorite deposition ended in the Late Eocene following the final collision of the Afro-Arabian Plate with Eurasia. The sub-aerial exposure of this formerly productive shallow-marine platform was the result of the separation of the Arabian Plate from the African Plate during the mid-Miocene.

scholarly journals Global Prevalence Estimates of Toxascaris leonina Infection in Dogs and Cats

Pathogens ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 503
Author(s):  
Ali Rostami ◽  
Seyed Mohammad Riahi ◽  
Vahid Fallah Omrani ◽  
Tao Wang ◽  
Andreas Hofmann ◽  
...  
Keyword(s):  
Mediterranean Region ◽  
Eastern Mediterranean ◽  
Meta Analysis ◽  
Eastern Mediterranean Region ◽  
Global Prevalence ◽  
Stray Cats ◽  
Prevalence Estimates ◽  
Meta Regression ◽  
Paratenic Hosts ◽  
Toxascaris Leonina

Toxascaris leonina is an ascaridoid nematode of dogs and cats; this parasite affects the health of these animals. This study estimated the global prevalence of Ta. leonina infection in dogs and cats using random effects meta-analysis as well as subgroup, meta-regression and heterogeneity analyses. The data were stratified according to geographical region, the type of dogs and cats and environmental variables. A quantitative analysis of 135 published studies, involving 119,317 dogs and 25,364 cats, estimated prevalence rates of Ta. leonina in dogs and cats at 2.9% and 3.4%, respectively. Prevalence was highest in the Eastern Mediterranean region (7.2% for dogs and 10.0% for cats) and was significantly higher in stray dogs (7.0% vs. 1.5%) and stray cats (7.5% vs. 1.8%) than in pets. The findings indicate that, worldwide, ~26 million dogs and ~23 million cats are infected with Ta. leonina; these animals would shed substantial numbers of Ta. leonina eggs into the environment each year and might represent reservoirs of infection to other accidental or paratenic hosts. It is important that populations of dogs and cats as well as other canids and felids be monitored and dewormed for Ta. leonina and (other) zoonotic helminths.

scholarly journals Primary care healthcare policy implementation in the Eastern Mediterranean region; experiences of six countries: Part II

2019 ◽  
Vol 26 (1) ◽  
pp. 1-6
Author(s):  
Nagwa Nashat ◽  
Redouane Hadjij ◽  
Abdul Munem Al Dabbagh ◽  
Mohammed Rasoul Tarawneh ◽  
Huda Alduwaisan ◽  
...  
Keyword(s):  
Primary Care ◽  
Policy Implementation ◽  
Mediterranean Region ◽  
Eastern Mediterranean ◽  
Eastern Mediterranean Region ◽  
Healthcare Policy

scholarly journals Correction to: A systematic review on hospital inefficiency in the Eastern Mediterranean Region: sources and solutions

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Hamid Ravaghi ◽  
Mahnaz Afshari ◽  
Parvaneh Isfahani ◽  
Victoria D. Bélorgeot
Keyword(s):  
Systematic Review ◽  
Mediterranean Region ◽  
Eastern Mediterranean ◽  
Eastern Mediterranean Region ◽  
Original Publication

In the original publication of this article [1], one author’s name needs to be revised from Pavaneh Isfahani to Parvaneh Isfahani.

scholarly journals COVID-19 Pandemic Affects the Medical Students’ Learning Process and Assaults Their Psychological Wellbeing

2021 ◽  
Vol 18 (11) ◽  
pp. 5792
Author(s):  
Marium Aftab ◽  
Alsaleem Mohammed Abadi ◽  
Shamsun Nahar ◽  
Razia Aftab Ahmed ◽  
Syed Esam Mahmood ◽  
...  
Keyword(s):  
Medical Students ◽  
Psychiatric Illness ◽  
Eastern Mediterranean ◽  
Learning Difficulties ◽  
Eastern Mediterranean Region ◽  
Female Gender ◽  
Psychological Wellbeing ◽  
Post Traumatic Stress ◽  
African Region ◽  
Cross Sectional

Background: With the emergence of the COVID-19 pandemic, people are living within a milieu of stress, anxiety, and fear. Medical students are susceptible to these emotional injuries, but their psychological wellbeing and learning may further be assaulted by future uncertainties and altered teaching and training programs. Our objective was to find the extent of the psychological impact of the pandemic and the learning difficulties they are experiencing; Methodology: This cross-sectional study included 418 undergraduate and postgraduate medical students from all over the world. A questionnaire was uploaded in Google survey form. It included background characteristics, questions for psychiatric impact like PHQ-9, GAD-7, ZF-OCS, and questions for learning difficulties perceived in comparison to the pre-pandemic time. Results: Among participants, 34.9% of students were male and 65.1% female. Around 46.4% belonged to the WHO, Eastern Mediterranean region, 26.8% from South East Asia region, 17.5% from the region of America, 5.5% from the European region,2.2%from the Western Pacific region, and 1.7% from the African region. Symptoms due to psychiatric illness were noticed in 393 (93.1%); depression in 386 (92.3%), anxiety in 158 (37.8%), obsessive compulsion disorder in 225 (53.8%), and post-traumatic stress syndrome in 129 (39.9%). Female gender, geographical region, and history of previous psychiatric illness were significantly related to almost all the psychiatric illnesses. Regarding learning difficulty, 96% of students faced problems: trouble with memorizing in 54.0%, concentration problems in 67.0%, about 55.5% of students made more mistakes, while 44.5% noted an increase in reaction time for solving questions. In addition, 90% experienced greater difficulty in overall learning during the pandemic in comparison to the pre-pandemic time. Conclusion: Assault on psychological wellbeing, struggling to memorize, inattention and difficulty in concentration on studies, along with perceived overall trouble with learning, have emerged as collateral damage from the COVID-19 pandemic with respect to medical students.

scholarly journals Effectiveness of Community Nutrition-Specific Interventions on Improving Malnutrition of Children under 5 Years of Age in the Eastern Mediterranean Region: A Systematic Review and Meta-Analysis

2021 ◽  
Vol 18 (15) ◽  
pp. 7844
Author(s):  
Delaram Ghodsi ◽  
Nasrin Omidvar ◽  
Bahareh Nikooyeh ◽  
Roshanak Roustaee ◽  
Elham Shakibazadeh ◽  
...  
Keyword(s):  
Cost Effectiveness ◽  
Mediterranean Region ◽  
Eastern Mediterranean ◽  
Meta Analysis ◽  
Eastern Mediterranean Region ◽  
Child Malnutrition ◽  
Z Score ◽  
Community Based ◽  
Nutritional Status Of Children ◽  
Children Under 5

Childhood malnutrition remains an important public health and development problem in low- and middle-income countries. This study aimed to systematically review the community-based nutrition-specific interventions and their effectiveness and/or cost-effectiveness on the nutritional status of children under 5 years of age in the Eastern Mediterranean Region (EMR). A systematic literature search of the English electronic databases, including PubMed, Scopus, ISI Web of Knowledge, Ovid, EMBASE, as well as Persian databases (SID and Magiran) was performed up to May 2019. Studies regarding the effectiveness/cost-effectiveness of the community-based nutrition-specific programs and interventions targeted at under-five-year children in EMR countries were selected. The primary outcomes were mean of Weight-for-age z-score (WAZ), Height-for-Age z-score (HAZ), and Weight-for-Height z-score (WHZ) of children or prevalence of wasting, stunting, and/or underweight among the children. Meta-analysis was also performed on the selected articles and intervention effects (mean differences) were calculated for each outcome for each study and pooled using a weighted random effects model. Risk of bias (ROB) of each included study was assessed based on the Cochrane Handbook for Systematic Reviews. The study protocol was registered in PROSPERO (CRD42020172643). Of 1036 identified studies, eight met the inclusion criteria. Amongst these, seven were from Pakistan and one from Iran. Only one study conducted in Pakistan reported the cost-effectiveness of nutrition-specific interventions in the region. Nutrition education/consultation and cash-based interventions were the most common nutrition-specific strategies used for management of child malnutrition in the EMR countries. Out of these eight studies, four were included in the meta-analysis. When different interventions were pooled, they had resulted in a significant improvement in WHZ of children (MD: 0.26; 95% CI: 0.07 to 0.46, three studies, I2 82.40%). Considering the high prevalence of child malnutrition in a number of countries in the region, capacity building and investigation regarding the implementation of new approaches to improve nutritional status of children and their effect(s) and cost-effectiveness assessment are highly recommended.

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