Energy transfer from the freshwater to the wastewater network using a PAT-equipped turbopump

A new strategy to increase the energy efficiency in a water network exists using turbo pumps, which are systems consisting of a pump and a turbine directly coupled on a same shaft. In a turbo pump, the pump is fed by a turbine that exploits a surplus head in a freshwater network in order to produce energy for one system (wastewater) and reduce the excess pressure in another (drinking water). A pump as turbine (PAT) may be preferred over a classic turbine here due to its lower cost. The result of such a coupling is a PAT-pump turbocharger (P&P). In this research, the theoretical performance of a P&P plant is employed using data from a real water distribution network to exploit the excess pressure of a freshwater stream and to feed a pump conveying wastewater toward a treatment plant. Therefore, the P&P plant is a mixed PAT-pump turbocharger, operating with both fresh and wastewater. A new method to perform a preliminary geometric selection of the machines constituting the P&P plant has been developed. Furthermore, the plant operation has been described by means of a new mathematical model under different boundary conditions. Moreover, the economic viability of the plant has been assessed by comparison with a conventional wastewater pumping system working in ON/OFF mode. Therefore, the net present value (NPV) of the investment has been evaluated in both situations for different time periods. According to the economical comparison, the PAT-pump turbocharger represents the most economically advantageous configuration, at least until the useful life of the plant. Such convenience amounts to 175% up to a time period equal to 20 years

Converging Role for REEP1/SPG31 in Oxidative Stress

Mutations in the receptor expression-enhancing protein 1 gene (REEP1) are associated with hereditary spastic paraplegia type 31 (SPG31), a neurological disorder characterized by lengthdependent degeneration of upper motor neuron axons. Mitochondrial dysfunctions have been observed in patients harboring pathogenic variants in REEP1, suggesting a key role of bioenergetics in disease-related manifestations. Nevertheless, the regulation of mitochondrial function in SPG31 remains unclear. To elucidate the pathophysiology underlying REEP1 deficiency, we analyzed in vitro the impact of two different mutations on mitochondrial metabolism. Together with mitochondrial morphology abnormalities, loss-of-REEP1 expression highlighted a reduced ATP production with increased susceptibility to oxidative stress. Furthermore, to translate these findings from in vitro to preclinical models, we knocked down REEP1 in zebrafish. Zebrafish larvae showed a significant defect in motor axon outgrowth leading to motor impairment, mitochondrial dysfunction, and reactive oxygen species accumulation. Protective antioxidant agents such as resveratrol rescued free radical overproduction and ameliorated the SPG31 phenotype both in vitro and in vivo. Together, our findings offer new opportunities to counteract neurodegeneration in SPG31

Stoics against stoics in Cudworth's "A Treatise of Freewill"

In his 'A Treatise of Freewill', Ralph Cudworth argues against Stoic determinism by drawing on what he takes to be other concepts found in Stoicism, notably the claim that some things are ‘up to us’ and that these things are the product of our choice. These concepts are central to the late Stoic Epictetus and it appears at first glance as if Cudworth is opposing late Stoic voluntarism against early Stoic determinism. This paper argues that in fact, despite his claim to be drawing on Stoic doctrine, Cudworth uses these terms with a meaning first articulated only later, by the Peripatetic commentator Alexander of Aphrodisias

How many leads through persistent left superior vein cava and coronary sinus?

In the modern implanting era with progressive expanding indications to resynchronization therapy, upgrading procedure is a relatively common event. Persistent left superior vena cava (PLSVC), the most common venous abnormality, may exacerbate technical difficulties. We describe the procedure of upgrading from a dual chamber pacemaker to resynchronization/defibrillation system with a total of 4 leads through a PLSVC entering a dilated coronary sinus (CS) never described before. The case report, in addition to the description of a unique technical approach, raises a lot of clinical questions about how many leads we can introduce in such a venous structure and inside CS without hemodynamic impact on venous drainage potentially leading to life-threatening situations

A new mixed integer non-linear programming model for optimal PAT and PRV location in water distributionnetworks

Water distribution network are energy-demanding systems affected by low efficiency. In such systems, the pressure is generally kept under control by regulation valves to reduce the waste of water due to the leakages. The employment of energy production devices may be an efficient strategy to both reduce waste of water and produce energy, whose feasibility basically depends on the amount of recoverable energy, though. In this study, the optimal location of both pumps as turbines (PATs) and pressure-reducing valves (PRVs) within a literature water distribution network is investigated to maximize the production of energy and water savings. A new mixed integer non-linear model has been developed and a global optimization solver has been employed to perform the optimization. According to the results, the new optimization ensures good solutions, in term of water and energy savings, when compared with other procedures in literature