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With the advancement of the next generation of cellular systems, flexible mechanisms for Discontinuous Reception (DRX) are needed in order to save energy. 5G will bring heterogeneous packet sizes and traffic types, as well as an increasing need for energy efficiency. The current static DRX mechanism is inadequate to meet these needs. In this paper we exploit channel prediction to develop integer programming models. We aim to minimize the energy usage of user devices while streaming video, as well as to create extended sleep opportunities, while simultaneously preventing buffer underflows. We also develop an online algorithm to obtain an efficient solution robust to prediction errors. Our results show that using a variable DRX cycle length can reduce the energy usage by up to 60 percent and 40 percent, in the offline and online cases, respectively, compared with a static DRX configuration. Our proposed online algorithm can also reduce the number of buffer underflows by up to 97 percent compared to the offline case. Both our online and offline solutions can provide extended DRX opportunities, which is required in 5G scenarios. [ABSTRACT FROM AUTHOR]

Objectives: To characterize current practice in fluid administration and deresuscitation (removal of fluid using diuretics or renal replacement therapy), the relationship between fluid balance, deresuscitative measures, and outcomes and to identify risk factors for positive fluid balance in critical illness.Design: Retrospective cohort study.Setting: Ten ICUs in the United Kingdom and Canada.Patients: Adults receiving invasive mechanical ventilation for a minimum of 24 hours.Interventions: None.Measurements and Main Results: Four-hundred patients were included. Positive cumulative fluid balance (fluid input greater than output) occurred in 87.3%: the largest contributions to fluid input were from medications and maintenance fluids rather than resuscitative IV fluids. In a multivariate logistic regression model, fluid balance on day 3 was an independent risk factor for 30-day mortality (odds ratio 1.26/L [95% CI, 1.07-1.46]), whereas negative fluid balance achieved in the context of deresuscitative measures was associated with lower mortality. Independent predictors of greater fluid balance included treatment in a Canadian site.Conclusions: Fluid balance is a practice-dependent and potentially modifiable risk factor for adverse outcomes in critical illness. Negative fluid balance achieved with deresuscitation on day 3 of ICU stay is associated with improved patient outcomes. Minimization of day 3 fluid balance by limiting maintenance fluid intake and drug diluents, and using deresuscitative measures, represents a potentially beneficial therapeutic strategy which merits investigation in randomized trials. [ABSTRACT FROM AUTHOR]

Non-melanomatous skin cancers represent 80% of all newly diagnosed cancers in Australia with basal cell carcinoma ( BCC) and squamous cell carcinoma ( SCC) being the most common. A previously healthy 71-year-old woman presented with widespread and tender superficial skin cancers on the lower bilateral limbs. External beam radiation therapy through the use of intensity-modulated radiation therapy ( IMRT) was employed as the treatment modality of choice as this technique provides conformal dose distribution to a three-dimensional treatment volume while reducing toxicity to surrounding tissues. The patient was prescribed a dose of 60 Gy to the planning target volume ( PTV) with 1.0 cm bolus over the ventral surface of each limb. The beam arrangement consisted of six treatment fields that avoided entry and exit through the contralateral limb. The treatment plans met the International Commission on Radiation Units and Measurements ( ICRU) guidelines and produced highly conformal dosimetric results. Skin toxicity was measured against the National Cancer Institute: Common Terminology Criteria for Adverse Events ( NCI: CTCAE) version 3. A well-tolerated treatment was delivered with excellent results given the initial extent of the disease. This case study has demonstrated the feasibility and effectiveness of IMRT for skin cancers as an alternative to surgery and traditional superficial radiation therapy, utilising a complex PTV of the extremities for patients with similar presentations. [ABSTRACT FROM AUTHOR]

We investigate the trade-off between energy usage and (packet) throughput in wireless mesh networks performing machine-to-machine communication. For this we provide a novel mixed-integer programming formulation to maximise the throughput while maintaining minimal energy usage, together with an effective price-and-branch solution algorithm based on column generation. The resulting optimisation model is the main original contribution of the presented paper. We conducted a numerical study using network examples from 10 to 40 nodes, in which periodic sensor measurements are aggregated and disseminated to actuators. In almost all cases, we were able to achieve maximum throughput and minimum energy usage simultaneously, and in those cases where this was not possible, the costs incurred in one objective in order to achieve the other were typically low. The solution times for all network sizes were of the order of seconds, showing that our optimisation model is feasible to use in practice. [ABSTRACT FROM AUTHOR]