Impartiality among UN Peacekeepers is key to ending communal violence in sub-Saharan Africa

Communal disputes over local issues such as land use, cattle herding, and access to scarce resources are a leading cause of conflict around the world. Despite abundant evidence that peacekeepers limit large-scale fighting between armed groups, we know little about their ability to prevent more localised forms of violence. William G. Nomikos explains the conditions under which UN peacekeeping operations promote peaceful interactions between civilian communities in fragile settings

Understanding the fundamentals of freight markets volatility

We analyse empirically the drivers of freight market volatility. We use several macroeconomic and shipping-related factors that are known to affect the supply and demand for shipping and examine their impact on the term structure of freight options implied volatilities (IV). We find that the level of IVs is affected by the level of the spot rate, the slope of the forward curve, as well as by both demand and supply factors, especially the former. We demonstrate that the relation between the volatility of futures prices and the slope of the forward curve is non-monotonic and convex, that is, it has a V-shape. In general, anticipation of economic growth and of a stronger freight market reduces IV whereas higher uncertainty and anticipation of excess shipping capacity may increase IV. Panel regressions as well as a series of robustness tests produce strong validation of the results

A meta-analysis of the efficacy of vortioxetine in patients with major depressive disorder (MDD) and high levels of anxiety symptoms

Background: Comorbid anxiety is common in major depressive disorder (MDD) and more difficult to treat than depression without anxiety. This analysis assessed the efficacy, safety, and tolerability of vortioxetine in MDD patients with high levels of anxiety (baseline Hamilton Anxiety Rating Scale [HAM-A] total score ?20).Methods: Efficacy was assessed using an aggregated, study-level meta-analysis of 10 randomized, placebo-controlled, 6/8-week trials of vortioxetine 5-20 mg/day in adults (18-75 years), with a study in elderly patients (?65 years) analyzed separately. Outcome measures included mean differences from placebo in change from baseline to endpoint (?) in the Montgomery-Åsberg Depression Rating Scale (MADRS), HAM-A total, and HAM-A subscales. Safety and tolerability were assessed by treatment-emergent adverse events (TEAEs).Results: A total of 1497 (48.6%) vortioxetine-treated and 860 (49.1%) placebo-treated patients had baseline HAM-A?20. There were significant differences from placebo in MADRS (vortioxetine 5 mg/day, n=415, ??2.68, P=0.005; 10 mg/day, n=373, ??3.59, P<0.001; 20 mg/day, n=207, ??4.30, P=0.005) and HAM-A total (5 mg/day, n=419, ??1.64, P=0.022; 10 mg/day, n=373, ??2.04, P=0.003; 20 mg/day, n=207, ??2.19, P=0.027). There were significantly greater improvements versus placebo on the HAM-A psychic subscale for all doses. The most common TEAEs (?5.0%) were nausea, headache, dizziness, dry mouth, diarrhea, nasopharyngitis, constipation, and vomiting. Incidence of serious TEAEs was 1.3% (placebo) and ?1.3% (vortioxetine, across doses).Limitations: Study heterogeneity limits this analysis. Patients with baseline HAM-A?20 were not directly compared to baseline HAM-A<20 or total MDD population.Conclusions: Vortioxetine was efficacious in reducing depressive and anxiety symptoms in patients with MDD and high levels of anxiety

Power system static and dynamic security studies for the 1st phase of Crete Island Interconnection

The island of Crete is currently served by an autonomous electrical system being fed by oil-fired (Heavy fuel or light Diesel oil) thermal power plants and renewables (wind and PVs). The peak load and annual electric energy consumption are approximately 600 MW and 3 TWh respectively; wind and photovoltaic parks contribute approximately 20% of the electricity needs of the island. Due to the expensive fuel used, the Cretan power system has very high electric energy generation cost compared to the Greek mainland. On the other side the limited size of the system poses severe limitations to the penetration of renewable energy sources, not allowing to further exploit the high wind and solar potential of the island. According to the Ten Year Network Development Plan (TYNDP) of the Greek TSO (Independent Power Transmission Operator S.A. IPTO S.A.), the interconnection of Crete to the mainland Transmission System of Greece will be realized through two links: A 150 kV HVAC link between the Peloponnese and the Crete (Phase I) and a HVDC link connecting the metropolitan area of Athens with Crete (Phase II). The total length of submarine and underground cable of the HVAC link will be approximately 174km; it is at the limits of the AC technology and the longest and deepest worldwide at 150 kV level. A number of studies have been conducted by a joint group of IPTO and Hellenic Electricity Distribution Network Operator (HEDNO) for the design of this interconnection. This paper presents briefly the power system static and dynamic studies conducted for the design of the AC link and its operation. Firstly, the paper presents the main results of the static security study regarding the calculation of the maximum power transfer capability of the link and the selection of the reactive power compensation scheme of the cable. Results from dynamic security analysis studies are also presented. The small-signal stability analysis concludes that a new (intra-area) electromechanical oscillation is introduced to the National System after the interconnection. The damping of the electromechanical oscillations is sufficient; however the operation of power system stabilizers at power plants located both at the mainland and at Crete power system can increase significantly the damping of important oscillation modes. Finally with respect to the risk of loss of synchronism after a significant disturbance in the system of Crete, such as a three-phase fault (“transient stability”)- enough safety margin is estimated by means of Critical Clearing Time calculations

Power system static and dynamic security studies for the 1st phase of Crete Island Interconnection

The island of Crete is currently served by an autonomous electrical system being fed by oil-fired (Heavy fuel or light Diesel oil) thermal power plants and renewables (wind and PVs). The peak load and annual electric energy consumption are approximately 600 MW and 3 TWh respectively; wind and photovoltaic parks contribute approximately 20% of the electricity needs of the island. Due to the expensive fuel used, the Cretan power system has very high electric energy generation cost compared to the Greek mainland. On the other side the limited size of the system poses severe limitations to the penetration of renewable energy sources, not allowing to further exploit the high wind and solar potential of the island. According to the Ten Year Network Development Plan (TYNDP) of the Greek TSO (Independent Power Transmission Operator S.A. IPTO S.A.), the interconnection of Crete to the mainland Transmission System of Greece will be realized through two links: A 150 kV HVAC link between the Peloponnese and the Crete (Phase I) and a HVDC link connecting the metropolitan area of Athens with Crete (Phase II). The total length of submarine and underground cable of the HVAC link will be approximately 174km; it is at the limits of the AC technology and the longest and deepest worldwide at 150 kV level. A number of studies have been conducted by a joint group of IPTO and Hellenic Electricity Distribution Network Operator (HEDNO) for the design of this interconnection. This paper presents briefly the power system static and dynamic studies conducted for the design of the AC link and its operation. Firstly, the paper presents the main results of the static security study regarding the calculation of the maximum power transfer capability of the link and the selection of the reactive power compensation scheme of the cable. Results from dynamic security analysis studies are also presented. The small-signal stability analysis concludes that a new (intra-area) electromechanical oscillation is introduced to the National System after the interconnection. The damping of the electromechanical oscillations is sufficient; however the operation of power system stabilizers at power plants located both at the mainland and at Crete power system can increase significantly the damping of important oscillation modes. Finally with respect to the risk of loss of synchronism after a significant disturbance in the system of Crete, such as a three-phase fault (“transient stability”)- enough safety margin is estimated by means of Critical Clearing Time calculations