168 research outputs found
Water Exchange through Canal İstanbul and Bosphorus Strait
The Turkish Straits System (TSS) regulates the transports of water, material and energy between the Black Sea and the Mediterranean Sea. Amidst existing environmental threats to the region surrounding İstanbul, the environmental footprint of the proposed Canal İstanbul project needs to be evaluated through methods of natural science. We take the elementary step to answer the particular problem of coupled strait dynamics by adding the Canal to an existing hydrodynamic model and estimate changes in their common response. Compared to the virtually unmodified exchange flow in the Bosphorus, the flow in the Canal has a weak lower layer current component, contrasted with intense currents at the exit controls at its junction with the Marmara Sea. The net flux through this simplest hypothetical TSS configuration is considerably increased for a given sea level difference across the system. The modified regime is expected to have climatological consequences
Modelling seasonal circulation and thermohaline structure of the Caspian Sea
Abstract. The wind- and buoyancy-driven seasonal circulation of the Caspian Sea is investigated for a better understanding of its basin-wide and mesoscale dynamics, mixing and transport. The model successfully reproduces the following basic elements of the circulation: the southward-flowing current systems along the eastern and western coasts, the upwelling along the eastern coast, the cyclonic circulation in the Middle Caspian Sea (MCS), especially in winter, and the cyclonic and anticyclonic cells of circulation in the South Caspian Sea (SCS). The observed seasonal variability of sea level and sea surface temperature (SST) is well reproduced. Mesoscale structures, not always evident from hydrographic observations, are identified.
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The Big Five and dark triad personality traits as predictors of emotional labour
Objective: Emotional labour is expected, especially from service sector employees, to ensure customer satisfaction and meet corporate expectations. Previous studies have mainly focused on the effects of emotional labour on employees. Few studies have examined its predictors in terms of personality traits. In the present study, the predictive levels of the Big Five and dark triad traits on emotional labour were examined possibly for the first time.
Method: Four hundred and seventy-three service sector employees participated in the research. Data were collected using an online survey comprising questions relating to the Big Five personality traits, dark triad personality traits, emotional labour and personal (demographic) information. Descriptive statistics, internal consistency test, Pearson’s correlation and hierarchical regression were used to analyse the data.
Results: According to the findings, Machiavellianism was the strongest predictor of surface acting, and agreeableness was the strongest predictor of deep acting and naturally felt emotions. Narcissism was found to be a predictor of surface acting.
Conclusions: As a result of examining the Big Five and dark triad traits in predicting emotional labour styles, the fact that agreeableness predicted deep acting and naturally felt emotions suggests that agreeableness should be given closer attention in recruitment and promotion decisions, especially in the service sector
Flow dynamics and mixing processes in hydraulic jump arrays: Implications for channel-lobe transition zones
A detailed field investigation of a saline gravity current in the southwest Black Sea has enabled the first complete analysis of three-dimensional flow structure and dynamics of a series of linked hydraulic jumps in stratified, density-driven, flows. These field observations were collected using an acoustic Doppler current profiler mounted on an autonomous underwater vehicle, and reveal that internal mixing processes in hydraulic jumps, including flow expansion and recirculation, provide a previously unrecognised mechanism for grain-size sorting and segregation in stratified density-driven flows. Field observations suggest a newly identified type of hydraulic jump, that is a stratified low Froude number (< 1.5–2) subaqueous hydraulic jump, with an enhanced ability to transport sediment downstream of the jump, in comparison to hydraulic jumps in other subaerial and submarine flows. These novel field data underpin a new process-based conceptual model of channel lobe transition zones (CLTZs) that explains the scattered offset nature of scours within such settings, the temporal variations in infill and erosion between adjacent scours, how bed shear stresses are maintained across the CLTZ, and why the locus of deposition is so far downstream of the scour zone
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Work addiction and its relation with dark personality traits: a cross-sectional study with private sector employees
Personality traits have been extensively studied to understand different behavioral addictions. However, less is known about the relationship of employees’ dark personality traits and work addiction. The purpose of the present study was to examine the associations between the Big Five personality traits (i.e., extroversion, neuroticism, agreeableness, openness, conscientiousness) and dark personality traits (i.e., narcissism, Machiavellianism, psychopathy, sadism, and spitefulness) with work addiction. A total of 514 private sector employees completed a survey that included psychometric assessment tools for the aforementioned variables. Hierarchical regression analysis indicated that lower extroversion, lower openness to experience, higher narcissism, and higher spitefulness were positively associated with work addiction among private sector employees. The findings of the present study suggest that dark personality traits should also be taken into account in order to better understand work addiction among employees
The biological activities and phytochemical content of Ferulago humulis Boiss.
Ferulago humulis Boiss. is an endemic species growing in Turkey. The aim of the study was to compare in vitro antioxidant and antimicrobial activities of the aerial parts (HFH) and rhizomes (RFH) of F. humulis. According to the results of antimicrobial and antioxidant activities of the extracts obtained from different parts of the plant, their phytochemical contents were evaluated. Petroleum ether (HFH-PE; RFH-PE), dichloromethane (HFH-DM; RFH-DM) and methanol (HFH-ME; RFH-ME) extracts from aerial parts (HFH) and rhizomes (RFH) of F. humulis were obtained for antimicrobial activity and examined by the agar hole diffusion and microdilution methods. Chromatographic and spectroscopic (1H NMR, LS-MS and UV) techniques were used for the isolation of coumarin compounds from petroleum ether (RFH-PE) and dichloromethane (RFH-DM) extracts. Furthermore, antioxidant activity were assayed by the 4 different methods in methanol extracts (HFH-ME; RFH-ME). HFH-PE (MIC=6.25 mg/mL), RFH-PE (MIC=12.5 mg/mL) and RFH-DM (MIC=11 mg/mL) extracts against Staphylococcus aureus, and RFH-PE (MIC= 3.125 mg/mL), HFH-PE (MIC=6.25 mg/mL) extracts showed antimicrobial activity against S. epidermidis. HFH-PE (MIC=1.56 mg/mL), RFH-PE (MIC= 6.25 mg/mL) extracts exhibited antifungal activity against Candida tropicalis. From the rhizomes of F. humulis isoimperatorin, bergapten, oxypeucedanin, marmesin senecioate and oxypeucedanin hydrate known as furanocoumarins derivatives were isolated
The biological activities and phytochemical content of Ferulago humulis Boiss.
728-735Ferulago humulis Boiss. is an endemic species growing in Turkey. The aim of the study was to compare in vitro antioxidant and antimicrobial activities of the aerial parts (HFH) and rhizomes (RFH) of F. humulis. According to the results of antimicrobial and antioxidant activities of the extracts obtained from different parts of the plant, their phytochemical contents were evaluated. Petroleum ether (HFH-PE; RFH-PE), dichloromethane (HFH-DM; RFH-DM) and methanol (HFH-ME; RFH-ME) extracts from aerial parts (HFH) and rhizomes (RFH) of F. humulis were obtained for antimicrobial activity and examined by the agar hole diffusion and microdilution methods. Chromatographic and spectroscopic (1H NMR, LS-MS and UV) techniques were used for the isolation of coumarin compounds from petroleum ether (RFH-PE) and dichloromethane (RFH-DM) extracts. Furthermore, antioxidant activity were assayed by the 4 different methods in methanol extracts (HFH-ME; RFH-ME). HFH-PE (MIC=6.25 mg/mL), RFH-PE (MIC=12.5 mg/mL) and RFH-DM (MIC=11 mg/mL) extracts against Staphylococcus aureus, and RFH-PE (MIC= 3.125 mg/mL), HFH-PE (MIC=6.25 mg/mL) extracts showed antimicrobial activity against S. epidermidis. HFH-PE (MIC=1.56 mg/mL), RFH-PE (MIC= 6.25 mg/mL) extracts exhibited antifungal activity against Candida tropicalis. From the rhizomes of F. humulis isoimperatorin, bergapten, oxypeucedanin, marmesin senecioate and oxypeucedanin hydrate known as furanocoumarins derivatives were isolated
Temporal nutrient dynamics in the Mediterranean Sea in response to anthropogenic inputs
The temporal dynamics of the concentrations of nitrate (N), phosphate (P), and the N:P ratio in the upper water column (200-600m) of the Mediterranean (MED) Sea were investigated using observational data (~123,100 data points) collected between 1985 and 2014. The studied variables were found to evolve similarly in the western and eastern MED Sea. In both basins, the N concentration increased during the first part of the observational period (1985-1998), and the temporal trend of N was broadly consistent with the history of riverine and atmospheric nitrogen input from populated areas in Europe, with a lag period of 20years. In subsequent years, the N concentration was high and relatively constant between 1998 and 2005, after which N decreased gradually, although the decreasing trend was indistinct in the western basin. In particular, the trend of constant then declining N after 1998 is consistent with the history of pollutant nitrogen emissions from the European continent, allowing a 20 year lag following the introduction of regulation of pollutant nitrogen in the 1970s. The three-phase temporal transition in P in both basins was more consistent with the riverine phosphorus input, with a lag period of 20years. Our analysis indicates that the recent dynamics of N and P in the upper MED Sea has been sensitive to the dynamics of anthropogenic nitrogen and phosphorus input from atmospheric deposition and river
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