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This work introduces a decentralized mechanism for the fair and efficient allocation of limited community-central renewable energy sources (RESs) among consumers with diverse energy demand and risk attitude levels in an energy community. In the proposed non-cooperative game, the self-interested community members independently decide whether to compete or not for access to RESs during peak hours and shift their loads analogously. In the peak hours, a proportional allocation (PA) policy is used to allocate the limited RESs among the competitors. Conditions for the existence of a Nash equilibrium (NE) or dominant strategies in this non-cooperative game are derived, and closed-form expressions of the renewable energy demand and social cost are calculated. Moreover, a decentralized algorithm for choosing consumers’ strategies that lie on NE states is designed. The work shows that the risk attitude of the consumers can have a significant impact on the deviation of the induced social cost from the optimal cost as the latter derives by a centralized minimization with full access to all consumers information. Besides, the proposed decentralized mechanism with the PA policy is shown to attain a much lower social cost than one using the naive equal sharing policy.

Pubic rami fractures in the geriatric population are usually osteoporotic fractures resulting from low energy trauma and are characterized as stable injuries. Established treatment of these injuries is conservative, including rest, analgesic medication, and progressive active mobilization. These injuries are life-threatened when pubic rami fractures are accompanied by acute bleeding, either from an injury to a vessel (corona mortis) or from medication (anticoagulant or antiplatelet) for comorbidities, then. In this case study, we present the unusual case of an 82-year-old woman admitted to the emergency department 24 hours after a simple fall, causing nondisplacement osteoporotic pubic rami fracture, who, after 48 hours, developed a hematoma on the contralateral side of the pelvis, with progressive anemia and acute abdominal pain. This study has 2 objectives: to increase awareness of this life-threatening injury in the emergency department and to describe diagnosis and treatment modalities.

In this work, the metabolic uncoupler para-nitrophenol (pNP) was applied to suppress excess sludge production and to investigate its effects on the system’s performance and activated sludge community structure. The COD removal efficiency decreased from 99.0% to 89.5% prior to and after pNP addition, respectively. Application of pNP transiently reduced NH4+-N, NO3−-N and NO2−-N removal efficiencies, suggesting partial inhibition of both nitrifying and denitrifying activity. However, no changes in the relative abundance of the nitrifying bacteria occurred. Phosphorus removal efficiency was sharply reduced after pNP addition, as the consequence of hydrolysis of stored cell reserves. Tetrasphaera, a key polyphosphate accumulating organism, was also affected by the addition of pNP, a fact that highly influenced system’s ability to remove phosphorus. A drastic drop in Soluble Microbial Products (SMP) and Extracellular Polymeric Substances (EPS) was also detected shortly after the introduction of the uncoupler. On the other hand, MBR’s physicochemical parameters were restored to initial values a week after the addition of pNP. Moreover, remarkable changes in beta-diversity were noted after pNP addition. An increase of Bacteroidetes, Gammaproteobacteria and Firmicutes over Actinobacteria and Alphaproteobacteria was also observed after pNP addition.

Sensor networks require a simple and efficient medium access control policy achieving high system throughput with no or limited control overhead in order to increase the network lifetime by minimizing the energy consumed during transmission attempts. Time-spread multiple-access (TSMA) policies that have been proposed for ad hoc network environments, can also be employed in sensor networks, since no control overhead is introduced. However, they do not take advantage of any cross-layer information in order to exploit the idiosyncrasies of the particular sensor network environment such as the presence of typically static nodes and a common destination for the forwarded data. An adaptive probabilistic TSMA-based policy, that is proposed and analyzed in this paper, exploits these idiosyncrasies and achieves higher system throughput than the existing TSMA-based policies without any need for extra control overhead. As it is analytically shown in this paper, the proposed policy always outperforms the existing TSMA-based policies, if certain parameter values are properly set; the analysis also provides for these proper values. It is also shown that the proposed policy is characterized by a certain convergence period and that high system throughput is achieved for long convergence periods. The claims and expectations of the provided analysis are supported by simulation results presented in this paper.