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Introduction: Rheopheresis is an extracorporal selective double-filtration procedure with an initial separation of plasma from the whole blood and a further filtration of the plasma through a second filter in order to eliminate a certain number of high molecular weight proteins such LDL, Lp(a), fibrinogen, α2-macroglobulin, Factor von Willebrand, and IgM Immunoglobulin.Methods: In this narrative review we discuss the available data on the effects of Rheopheresis in various clinical conditions.Results: Rheopheresis is considerd to exert a rapid effect on clinical conditions associated with seriously affected microcirculation and rheologic parameters such as, the dry age-related macular degeneration (AMD), sudden sensorineural hearing loss (SSHS), peripheral artery disease (PAD), calciphylaxis, systemic sclerosis and diabetic foot.Conclusions: Rheopheresis is a promising technique for conditions associated with affected microcirculatory rheologic parameters

•Hybrid solar-biomass micro-CHP system to cover the energy demand of households.•Solar-biomass covers 97.10% and 25.85% of space heating and electricity demand.•Maximum exergy and total energy efficiency equal to 15.05% and 90.74%.•LCOE from 0.072 to 0.133 €/kWh, LCOH from 0.036 to 0.067 €/kWh.•31.22 kg CO2-eq. emissions reduction and 46.58 kWh primary energy savings per m2.

Currently, a noticeable lack of literature with respect to a wide-ranging comparison of the precision exhibited by automated and manual two-axis tracking solar systems, particularly within the context of adhering to the standard testing protocols delineated by ISO and IEC.

•Development of a robust and computationally-efficient thermodynamic model for the simulation of flashing in twin-screw expanders.•Low vapor qualities at the suction port of the two-phase expander lead to reduced isentropic efficiencies.•Selection between TFC and ORC must be based on performance optimization that takes into account the combination of operating conditions and expander characteristics.

Constipation in peritoneal dialysis (PD) is an infrequent but potentially serious condition affecting the mechanical properties of dialysis techniques and predisposing to bacterial intestinal translocation and eventual enteric peritonitis. Despite the importance of the problem, published literature is scarce, consisting mostly of uncontrolled single-center trials. This inconsistency may be attributed to the large number of clinical, radiological, and endoscopic tools that have been used in the studies with a lack of generally accepted core primary outcomes.The current narrative review discusses the pathophysiological associations between chronic kidney disease, PD, and constipation with related complication.

AbstractA major drawback of Reverse Osmosis (RO) desalination units is their poor performance at off-design conditions. On the other hand, they can operate with low specific energy consumption and produce high-quality fresh water when they are supplied with almost constant power, according to their design and nominal operating conditions. This aspect brings additional effort when there is the need to desalinate seawater or even brackish water using unsteady power sources, such as renewable energy systems powered by, for example, solar or wind energy. In order to overcome this issue, an alternative small-scale RO unit is investigated here, whose major advantage is that it can operate with almost constant specific energy consumption and produce high-quality fresh water with low Total Dissolved Solids (TDS) for a wide range of power input. Such unit is suitable to be combined with small-scale energy systems, which can have a very high variety on their power output, such as PV, wind turbines, or even solar Organic Rankine Cycle, for power production. The developed RO unit includes three identical sub-units, each placed on its own skid and with a fresh water capacity of 0.7 m3/h. An energy recovery unit of axial piston motor type is equipped at each sub-unit for decreasing its power consumption. These sub-units are switched on/off, according to the power availability, in order to operate them within a range, thus with high efficiency and acceptable fresh water quality. Such small-scale RO unit, capable of producing 2.1 m3/h of fresh water in total, is examined here, focusing on its operation, performance, and fresh water production. The main parameter adjusted is the power availability, ranging from almost zero up to the maximum value of 12 kW. The analysis first focuses on a single sub-unit, exploring its performance for variable power input, while afterwards all three sub-units are synthesized, in order to form the complete RO unit, concluding to the dependence of the fresh water production and specific energy consumption from the power supply. For the single RO sub-unit at low power input, the TDS level is very high, whereas the specific energy consumption is low, since the membrane pressure is much lower than the designed one and slightly above the osmotic pressure. For available power, more than around 1 kW, the TDS level holds acceptable values lower than 400–500 mg/l, which is achieved with the high pressurizing of the feed seawater, with specific energy consumption up to 4–5 kWh/m3. For power input higher than 3 kW, the second and third sub-units are successively switched on. In this case, the specific energy consumption is almost constant and equal to 4.5 kWh/m3, including the required power of the feed pump, while the produced fresh water TDS has small variations and is approximately equal to 200–250 mg/l.

A major drawback of Reverse Osmosis (RO) desalination units is their poor performance at off-design conditions. On the other hand, they can operate with low specific energy consumption and produce high-quality fresh water when they are supplied with almost constant power, according to their design and nominal operating conditions. This aspect brings additional effort when there is the need to desalinate seawater or even brackish water using unsteady power sources, such as renewable energy systems powered by, for example, solar or wind energy. In order to overcome this issue, an alternative small-scale RO unit is investigated here, whose major advantage is that it can operate with almost constant specific energy consumption and produce high-quality fresh water with low Total Dissolved Solids (TDS) for a wide range of power input. Such unit is suitable to be combined with small-scale energy systems, which can have a very high variety on their power output, such as PV, wind turbines, or even solar Organic Rankine Cycle, for power production. The developed RO unit includes three identical sub-units, each placed on its own skid and with a fresh water capacity of 0.7 m3/h. An energy recovery unit of axial piston motor type is equipped at each sub-unit for decreasing its power consumption. These sub-units are switched on/off, according to the power availability, in order to operate them within a range, thus with high efficiency and acceptable fresh water quality. Such small-scale RO unit, capable of producing 2.1 m3/h of fresh water in total, is examined here, focusing on its operation, performance, and fresh water production. The main parameter adjusted is the power availability, ranging from almost zero up to the maximum value of 12 kW. The analysis first focuses on a single sub-unit, exploring its performance for variable power input, while afterwards all three sub-units are synthesized, in order to form the complete RO unit, concluding to the dependence of the fresh water production and specific energy consumption from the power supply. For the single RO sub-unit at low power input, the TDS level is very high, whereas the specific energy consumption is low, since the membrane pressure is much lower than the designed one and slightly above the osmotic pressure. For available power, more than around 1 kW, the TDS level holds acceptable values lower than 400–500 mg/l, which is achieved with the high pressurizing of the feed seawater, with specific energy consumption up to 4–5 kWh/m3. For power input higher than 3 kW, the second and third sub-units are successively switched on. In this case, the specific energy consumption is almost constant and equal to 4.5 kWh/m3, including the required power of the feed pump, while the produced fresh water TDS has small variations and is approximately equal to 200–250 mg/l.

An integrated energy system for office buildings is examined, with the use of a numerical tool that has been developed for simulating renewable energy-based systems based on geothermal and solar energy. The main system components are the PV-Thermal (PVT) collectors, several boreholes that form a ground heat exchanger system and a multi-source heat pump supplied by heat either from the ambient air or water. The developed code in Python is used for the detailed investigation of the system performance over time, components’ sizing, as well as for analyzing various layouts. Different demand profiles have been considered according to the insulation level of the building, and the total PVT collector surface is varied from about 50 to 100 m². Focus is given here on the renewable energy share of the energy system for covering the heating and cooling demand of a typical office building in a warm climate (Athens, Greece) and in a cold one (Copenhagen, Denmark). Technical and environmental indicators are presented and compared with standard solutions. The results show that the heat pump can operate few moments during the day to charge the buffer tank, introducing high flexibility. Moreover, the annual COP in winter is over 4 in Athens and about 3.8 in Copenhagen. Self-consumption exceeds 30% in some cases in Athens, whereas is up to 11% in Copenhagen. Finally, considering rooftop limitations it is possible to reach 82% and 61% renewable share by adding standard PV panels in office buildings with moderate energy efficiency level in Athens and Copenhagen, respectively.

Background Regular or illegal drugs and toxins are the most frequent non-physical causes of rhabdomyolysis (RM) in peacetime. Acute Kidney Injury (AKI) is a serious and, sometimes, fatal complication of RM. It occurs in 8–20% of RM incidents.Methods In this prospective study we evaluated the severity of RM and AKI in narcotic drug users. From January 2001 to December 2007, 21 patients (17 males, mean age 27.8±4.8 years) with RM associated with AKI were classified into two groups: 11 heroin users (HU) and 10 non-heroin users (NHU). The severity of RM was evaluated by estimation, on admission, of serum creatine phosphokinase (CPK), serum glutamic oxaloacetic transaminase (SGOT), lactate dehydrogenase (LDH), phosphate (PO4) and calcium (Ca) and by the presence of paraplegia (PPL). The severity of AKI during hospitalization was evaluated by estimation of serum creatinine (CR), the presence of oligoanuria (OA), the days of hospitalization (DH), the total of hemodialysis treatments (THD) and the number of patients who received blood transfusions (BT).Results RM was much more severe in HU than in NHU. Mean SGOT, CPK, LDH, and P values on admission were higher in HU. Hypocalcemia was statistically more severe in HU. Nine HU were admitted with PPL vs. 1 NHU. Serum CR levels were higher and oligoanuria was much more common in HU. HU had a longer hospitalization period and underwent a bigger number of HT. More HU took BT.Conclusions The results of this study suggest that both RM and ARF are more severe in HU than in NHU possibly due to an additional myotoxic effect of heroin.

In this report we describe the case of a 65-year-old diabetic patient who developed hydronephrosis and irreversible end-stage renal disease nine years after the placement of an AMS 800™ artificial urinary sphincter. This was due to non-compliance with the voiding regime and lack of follow-up after the placement of the urinary sphincter.

•Detailed heat pump numerical model including the effect of nanoparticles.•Investigation of heat pump performance with different nanorefrigerants.•Heat transfer and pressure drop effects of nanorefrigerants.•COP increases up to 6% with nanorefrigerants at both heating and cooling modes.•The payback period can be as long as 6 years, having large uncertainty.