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Objectives: Readmission to intensive care unit (ICU) is associated with longer hospital stays, higher mortality, and increased health-care costs. In addition to the highly subjective nature of ICU discharge decisions, constraints in clinical resources and insufficient beds to admit all ICU patients may result in some patients being discharged from the ICU prematurely and readmitted. Methods: After obtaining approval from the local ethics committee of our hospital for our study, the files of ICU patients in 2019 and 2020 were retrospectively studied and data collected. Results: In 2020, the ICU bed rate was 43 (6.9%), 21 (3.4%) higher than in 2019. A total of 57 patients were readmitted per year. The readmission rate in 2019 was 40 (70.2%), 17 (29.8%) statistically significantly higher than in 2020. In 2019, mortality rate in readmitted patients (47.5%) was statistically significantly higher than ICU mortality rate (31.5%). No significant difference was found in 2020. Although mortality rates in readmissions in both years were higher than normal ICU mortality rate, there was no statistical difference between them. The most common reason for readmission in both years was acute respiratory failure and the most frequent readmissions were from general surgery and internal medicine wards. Conclusion: Overloading ICU capacity to treat critically ill patients can affect physician decision-making, leading to early discharge. Patients discharged from ICU always have the possibility for readmission. ICU readmissions are associated with much higher mortality rates than initial admission. Identifying high-risk patients and better ward care are key to reducing ICU readmission. [ABSTRACT FROM AUTHOR]

Selective targeting of transfected mesenchymal stem cells (MSCs) carrying specific antioncogenes to the tumor was suggested as a treatment option. Bone morphogenetic protein-2 (BMP2) was shown to inhibit the proliferation and aggressiveness of osteosarcoma (OS) cells. Here, we aimed to assess the homing efficiency of intraperitoneally administered hMSCs transfected with BMP2 to the tumoral site and their effects on OS using an orthotopic xenograft murine model. Orthotopic xenograft murine model of OS in six-week-old female NOD/SCID mice using 143B cells was established. hMSCs transfected with BMP2 (BMP2+hMSC) were used. In vivo experiments performed on four groups of mice that received no treatment, or intraperitoneally administered BMP2, hMSCs, and BMP2+hMSCs. Histopathological and immunohistochemical studies were used to evaluate the pathological identification and to assess the dimensions and necrotic foci of the tumor, the features of lung metastases, and immunostaining against p27, Ki-67, and caspase-3 antibodies. The osteogenic differentiation markers BMP2, BMP4, COL1A1, OPN, OCN and PF4 evaluated using RT-PCR. The tumor dimensions in the hMSCs group were significantly higher than those of the remaining groups (p < 0.01). The number of metastatic foci in the BMP2+hMSCs group was significantly lower than those of the other groups (p < 0.01). The current results showed that the intraperitoneal route could be efficiently used for targeting hMSCs to the tumoral tissues for effective BMP2 delivery. In this study, the effects of BMP2 transfected hMSCs on human OS and metastasis were promising for achieving osteogenic differentiation and reduced metastatic process. [ABSTRACT FROM AUTHOR]

Objective: The objectives of this study are to determine the problems of patients who underwent percutaneous tracheostomy opening in intensive care and then were discharged with a tracheostomy that had either spontaneous respiration or mechanical ventilation (MV) support, and decrease the morbidity and mortality of these patients by focusing on training their caregivers about potential problems. Materials and Methods: The files of 90 patients, who were admitted to the intensive care unit (ICU) between 2017 and 2018 with a tracheostomy, were analysed. Twenty-nine patients were discharged. Patients were grouped as cerebrovascular disease (CVD), respiratory failure (RF), neuromuscular diseases and others (Alzheimer’s, Parkinson’s). Patients and their caregivers were interviewed face-to-face or by telephone to obtain information about patients. The reasons for hospitalisation, Glasgow coma scale (GCS) score, feeding patterns, MV support, life expectancy and problems at home were recorded. Results: In 29 discharged patients, 14 of them were classified as CVD, five as RF, six as neuromuscular disease (NMD) and four as other. The mortality rates of patients with high GCS values (GCS-2) from ICU were found to be lower. The fatality rate for the NMD group (0%) was found to be significantly lower than that of CVD (64.3%) and RF (80%). Seven (50%) patients developed contracture or limited joint motion. Respiratory-related problems were the most common problems that patients experienced at home, and 12 (85.7%) had intense secretions. Constipation was the most common nutritional problem and was experienced by six patients (42.9%). Conclusion: The home care of patients with a tracheostomy requires specific procedures and may lead to the development of specific complications. In this study, we determined that the respiratory problems of home care patients, particularly those involving intense secretions, plugged the tracheostomy and required the need for MV. Another important problem is that patients have limited joint motion. Thus, before discharge, patients should be trained consistently. [ABSTRACT FROM AUTHOR]

Objective: This study aims to determine the changes of anxiety-depression-stress levels in ICU personnel working on COVID-19 patients at an early stage, to set precautions so that they can feel secure and mentally relaxed during their work. Method: One month after starting to admit COVID-19 patients into our ICU, we planned a survey to determine above-mentioned changes in healthcare personnel, using standard scales (perceived stress level, Beck Anxiety Inventory, Beck’s Depression Inventory). Survey forms were filled in by 102 people in our ICU. Results: The rates of depression [58.8% (n=60)], anxiety [67.6 % (n=69)] and average perceived stress scale score (29.92±6.86) were determined. Men’s perceived stress scale scores were statistically significantly lower than women’s. Compared to other groups, among the people who previously received psychiatric support, depression rate was higher in 5 of 6 patients (83.3%) and anxiety in 6 of 6 (100 %) patients. The rate of Beck Anxiety Inventory scores in men (51.4 %) were statistically significantly lower than in women (76.1 %). Similarly, prevalence of anxiety was at higher level (76.2 %) in healthcare personnel with children. Conclusion: These outbreaks can re-occur in future and create more challenging cases. Therefore, countries should prepare their health systems, especially healthcare professionals, against sudden work overloads to prevent serious psychological problems in these professionals and in society. Healthcare personnel should receive support against mental problems and undergo periodical training to prevent further trauma and impact in future cases. Furthermore, in epidemic settings, preventive diagnosis and treatment studies should be carried out to tackle psychological problems commonly encountered in female healthcare personnel. [ABSTRACT FROM AUTHOR]

Summary: Fatty acids have been broadly used as phase change materials (PCMs) for thermal energy storage. However, low thermal conductivity limits their performances. This paper investigates the influence of metal oxide nanoparticle addition on myristic acid (MA) as nano‐enhanced PCM (NEPCM). Stability, chemical, and thermal properties were considered. Four types of nanoaprticles, TiO2, CuO, Al2O3, and ZnO, were dispersed in MA at 0.1, 0.5, 1, and 2 wt%. Stability and dispersion were checked by sediment photograph capturing and scanning electron microscopy/energy‐dispersive spectroscopy. The Fourier‐transformed infrared (FTIR) and X‐ray diffraction analysis confirmed no chemical interaction between the nanoparticles and MA. The results revealed a ratio of thermal conductivity of 1.50, 1.49, 1.45, and 1.37, respectively, for 2 wt% of ZnO, Al2O3, CuO, and TiO2. The T‐history method confirmed this enhancement. The latent heat thermal energy storage (LHTES) properties of the nano‐enhanced MA were evaluated using differential scanning calorimetry. The latent heat capacities of nano‐enhanced MA samples have dropped between 9.64 and 5.01 % compared with pure MA, and phase change temperature range was not affected significantly. The NEPCM was subjected to 500 thermal cycling, it showed a good thermal reliability as LHTES properties remained unchanged, while FTIR analysis showed similar characteristics compared with uncycled samples, indicating a good chemical stability. Based on the results regarding with the LHTES properties, cycling thermal reliability, and higher thermal conductivity improvement, it can be achieved that the MA/Al2O3 (2.0 wt%) and MA/ZnO (2.0 wt%) composites could be better PCMs for solar TES applications. [ABSTRACT FROM AUTHOR]

Abstract: This study aimed to investigate the adsorption and desorption potential of raw kaolinite (Kaol) and manganese oxide (MnO2)-modified kaolinite (MnO-Kaol) for the removal of cadmium (Cd(II)) ions from aqueous solution and waste water. The chemical and morphological characterizations of kaol and MnO-Kaol were carried out by using Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FT-IR) analysis methods. The BET surface analysis results showed that the specific surface area of kaol increased by about 68% after MnO2 modification. The cadmium adsorption feasibility of MnO-Kaol was examined systemically by evaluating the effects of initial pH of solution, contact time, adsorbent concentration, and temperature of solution on the adsorption efficiency. From the Langmuir model, the adsorption capacities of kaol and MnO-Kaol were found to be 14.11 and 36.47mgg−1. The Dubinin–Radushkevich (D–R) model showed that the Cd(II) adsorption onto MnO-Kaol was progressed essentially by chemical ion-exchange. The recovery test demonstrated that the MnO-Kaol has good reusability performance after repeated ten times adsorption–desorption cycles. The thermodynamic studies revealed that the adsorption process of Cd(II) onto MnO-Kaol has exothermic nature and more feasible with increasing temperature of solution. The kinetic investigations also denoted that the adsorption process better fits the pseudo-second-order kinetic model. [Copyright &y& Elsevier]

Abstract: In this study, four kinds of mannitol–fatty acid esters were synthesized as novel organic phase change materials (PCMs) for thermal energy storage applications. The structural characterization of synthesized mannitol hexastearate (MHS), mannitol hexapalmitate (MHP), mannitol hexamyristate (MHM) and mannitol hexalaurate (MHL) were carried out using Fourier Transform Infrared (FT-IR), Proton Nuclear Magnetic Resonance (1H NMR), and 13C NMR spectroscopy methods. Thermal energy storage properties and thermal reliability of the synthesized PCMs were determined using differential scanning calorimetry (DSC) method at a heating rate of 1°C/min. DSC results showed that the melting temperatures of the PCMs were in the temperature range of 42–65°C and their latent heat values spanned between 145 and 202J/g. The latent heats of these PCMs are low compared to mannitol but they fall into the same range as fatty acids. The synthesized PCMs have much lower phase change temperatures and supercooling degree (about 1–8°C) and compared to the mannitol. They have also better odor, noncorrosivity and thermal durability properties as compared to the fatty acids. Thermal cycling test consisted of repeated 1000 melting/solidification cycles also revealed that the synthesized PCMs have good thermal reliability. In addition, thermal conductivity of the PCMs was increased significantly by addition of expanded graphite (EG) at 10wt%. Based on all results it can be concluded that the synthesized PCMs, MHS, MHP, MHM and MHL esters can be considered as promising solid–liquid PCMs for solar heating applications. [Copyright &y& Elsevier]

Abstract: The equilibrium, thermodynamics and kinetics of the biosorption of Hg(II) onto moss (Drepanocladus revolvens) biomass from aqueous solution were investigated. Optimum experimental parameters were determined to be pH 5.5, contact time 60min, biomass concentration 4gL−1 of solution, and temperature 20°C. From the Langmuir model the maximum biosorption capacity of the moss biomass was found to be 94.4mgg−1. The mean free energy value (10.2kJmol−1) evaluated by using the Dubinin–Radushkevich (D–R) model indicated that the biosorption of mercury ions onto D. revolvens was taken place by chemical ion-exchange. The kinetic studies indicated that the biosorption process of mercury ions followed well pseudo-second-order model. The calculated thermodynamic parameters (ΔG°, ΔS°, ΔH°) showed the biosorption to be exothermic and spontaneous with decreased randomness at the solid–solution interface. The recovery of the Hg(II) from D. revolvens biomass was found to be 99% using 1M HCl. It was concluded that the D. revolvens biomass can be used as biosorbent for the treatment of wastewaters containing Hg(II) ions. [Copyright &y& Elsevier]

Abstract: The potential use of the lichen biomass (Xanthoparmelia conspersa) to remove mercury(II) ions from aqueous solution by biosorption was evaluated using the batch method. Effects of pH, contact time, biomass concentration and temperature on the removal of Hg(II) ions were studied. The Langmuir isotherm models defined the equilibrium data precisely compared to Freundlich model and the maximum biosorption capacity obtained was 82.8mgg−1. From the D–R isotherm model, the mean free energy was calculated as 9.5kJmol−1. It shows that the biosorption of Hg(II) ions onto X. conspersa biomass was taken place by chemical ion-exchange. Experimental data were also performed to the pseudo-first-order and pseudo-second-order kinetic models. The results indicated that the biosorption of Hg(II) on the lichen biomass followed well the second-order kinetics. Thermodynamic parameters, ΔG o, ΔH o and ΔS o indicated the Hg(II) sorption to be exothermic and spontaneous with decreased randomness at the solid–solution interface. Furthermore, the lichen biomass could be regenerated using 1M HCl, with up to 85% recovery, which allowed the reuse of the biomass in ten biosorption–desorption cycles without any considerable loss of biosorptive removal capacity. [Copyright &y& Elsevier]

Abstract: The equilibrium, thermodynamics and kinetics of the biosorption of Pb(II) and Cd(II) onto (Lactarius scrobiculatus) macrofungus from aqueous solution were investigated at different experimental conditions. Optimum experimental parameters were determined to be pH 5.5, contact time 60min, biomass concentration 4g/L of solution, and temperature 20°C. The maximum biosorption capacity of L. scrobiculatus was found to be 56.2mg/g for Pb(II) and to be 53.1mg/g for Cd(II). The mean free energy values evaluated by using the Dubinin–Radushkevich (D–R) model indicated that the biosorption of the metal ions onto L. scrobiculatus biomass was taken place by chemical ion-exchange. The kinetic studies indicated that the biosorption process of the metal ions followed well pseudo-second order model. The calculated thermodynamic parameters (ΔG°, ΔH° and ΔS°) showed that the biosorption of Pb(II) and Cd(II) ions onto L. scrobiculatus biomass was feasible, spontaneous and exothermic in nature. The recovery of the metal ions from L. scrobiculatus biomass was found as higher than 95% using 1M HCl and 1M HNO3. Furthermore, the reusability of the biosorbent was determined after six consecutive sorption-desorption cycles. [Copyright &y& Elsevier]

The biosorption potential of Racomitrium lanuginosum as aquatic moss biosorbent for the removal of Pd(II) from aqueous solution was investigated. The effects of pH, biomass dosage, contact time, and temperature on the biosorption processes were systematically studied. Experimental data were modeled by Langmuir, Freundlich and Dubinin–Radushkevich (D–R) isotherms. Langmuir isotherm model (R 2 =0.994) fitted the equilibrium data better than the Freundlich isotherm model (R 2 =0.935). The monolayer biosorption capacity of R. lanuginosum biomass for Pd(II) was found to be 37.2mg/g at pH 5. The mean free energy was calculated as 9.2kJ/mol using the D–R isotherm model (R 2 =0.996). This result indicated that the biosorption of Pd(II) was taken place by chemical ion-exchange. The calculated thermodynamic parameters, ΔG°, ΔH° and ΔS° showed that the biosorption of Pd(II) on R. lanuginosum biomass was feasible, spontaneous and exothermic under examined conditions. Experimental data were also tested using the biosorption kinetic models. The results showed that the biosorption processes of Pd(II) on R. lanuginosum followed well pseudo-second-order kinetics at 20–50°C (R 2 =0.999). [Copyright &y& Elsevier]

Abstract: The biosorption characteristics of Cd(II) and Cr(III) ions from aqueous solution using the moss (Hylocomium splendens) biomass were investigated in terms of equilibrium, kinetics and thermodynamics. Optimum biosorption conditions were determined as a function of pH, biomass dosage, contact time, and temperature. Langmuir, Freundlich and Dubinin–Radushkevich (D–R) models were applied to describe the biosorption isotherm of the metal ions by H. splendens biomass. Langmuir model fitted the equilibrium data better than the Freundlich isotherm. The maximum biosorption capacity (q m) of H. splendens biomass was found to be 32.5mg/g for Cd(II) ion and 42.1mg/g for Cr(III) ion. The mean free energy values evaluated from the D–R model indicated that the biosorption of Cd(II) and Cr(III) onto H. splendens biomass was taken place by chemical ion-exchange. The calculated thermodynamic parameters, ΔG°, ΔH° and ΔS° showed that the biosorption of Cd(II) and Cr(III) ions onto H. splendens biomass was feasible, spontaneous and exothermic under examined conditions. Experimental data were also tested in terms of biosorption kinetics using pseudo-first-order and pseudo-second-order kinetic models. The results showed that the biosorption processes of both metal ions followed well pseudo-second-order kinetics. [Copyright &y& Elsevier]

The adsorption of Cr(VI) from aqueous solution by Turkish vermiculite were investigated in terms of equilibrium, kinetics, and thermodynamics. Experimental parameters affecting the removal process such as pH of solution, adsorbent dosage, contact time, and temperature were studied. Equilibrium adsorption data were evaluated by Langmuir, Freundlich and Dubinin-Radushkevich (D-R) isotherm models. Langmuir model fitted the equilibrium data better than the Freundlich model. The monolayer adsorption capacity of Turkish vermiculite for Cr(VI) was found to be 87.7 mg/g at pH 1.5, 10 g/L adsorbent dosage and 20°C. The mean free energy of adsorption (5.9 kJ/mol) obtained from the D-R isotherm indicated that the type of sorption was essentially physical. The calculated thermodynamic parameters (ΔGo, ΔHo and ΔSo) showed that the removal of Cr(VI) ions from aqueous solution by the vermiculite was feasible, spontaneous and exothermic at 20-50°C. Equilibrium data were also tested using the adsorption kinetic models and the results showed that the adsorption processes of Cr(VI) onto Turkish vermiculite followed well pseudo-second order kinetics. [ABSTRACT FROM AUTHOR]

Abstract: The biosorption characteristics of Pb(II) and Cr(III) ions from aqueous solution using the lichen (Parmelina tiliaceae) biomass were investigated. Optimum biosorption conditions were determined as a function of pH, biomass dosage, contact time, and temperature. Langmuir, Freundlich and Dubinin–Radushkevich (D–R) models were applied to describe the biosorption isotherm of the metal ions by P. tiliaceae biomass. Langmuir model fitted the equilibrium data better than the Freundlich isotherm. The monolayer biosorption capacity of P. tiliaceae biomass for Pb(II) and Cr(III) ions was found to be 75.8mg/g and 52.1mg/g, respectively. From the D–R isotherm model, the mean free energy was calculated as 12.7kJ/mol for Pb(II) biosorption and 10.5kJ/mol for Cr(III) biosorption, indicating that the biosorption of both metal ions was taken place by chemical ion-exchange. The calculated thermodynamic parameters (ΔG°, ΔH° and ΔS°) showed that the biosorption of Pb(II) and Cr(III) ions onto P. tiliaceae biomass was feasible, spontaneous and exothermic under examined conditions. Experimental data were also tested in terms of biosorption kinetics using pseudo-first-order and pseudo-second-order kinetic models. The results showed that the biosorption processes of both metal ions followed well pseudo-second-order kinetics. [Copyright &y& Elsevier]

Abstract: Fatty acids such as stearic acid (SA), palmitic acid (PA), myristic acid (MA), and lauric acid (LA) are promising phase change materials (PCMs) for latent heat thermal energy storage (LHTES) applications, but high cost is the most drawback which limits the utility area of them in thermal energy storage. The use of fatty acids as form-stable PCM will increase their feasibilities in practical LHTES applications due to reduced cost of the energy storage system. In this regard, a series of fatty acid/poly(methyl methacrylate) (PMMA) blends, SA/PMMA, PA/PMMA, MA/PMMA, and LA/PMMA were prepared as new kinds of form-stable PCMs by encapsulation of fatty acids into PMMA which acts as supporting material. The blends were prepared at different mass fractions of fatty acids (50, 60, 70, 80, and 90%w/w) to reach maximum encapsulation ratio. All blends were subjected to leakage test by heating the blends over the melting temperature of the PCM. The blends that do not allow leakage of melted PCM were identified as form-stable PCMs. The form-stable fatty acid/PMMA (80/20wt.%) blends were characterized using optic microscopy (OM), viscosimetry, and Fourier transform infrared (FT-IR) spectroscopy methods, and the results showed that the PMMA was compatible with the fatty acids. In addition, thermal characteristics such as melting and freezing temperatures and latent heats of the form-stable PCMs were measured by using differential scanning calorimetry (DSC) technique and indicated that they had good thermal properties. On the basis of all results, it was concluded that form-stable fatty acid/PMMA blends had important potential for some practical LHTES applications such as under floor space heating of buildings and passive solar space heating of buildings by using wallboard, plasterboard or floor impregnated with a form-stable PCM due to their satisfying thermal properties, easily preparing in desired dimensions, direct usability without needing an add encapsulation and eliminating the thermal resistance caused by shell and thus reducing cost of LHTES system. [Copyright &y& Elsevier]

The adsorption of Pb(II) onto Turkish (Bandırma region) kaolinite clay was examined in aqueous solution with respect to the pH, adsorbent dosage, contact time, and temperature. The linear Langmuir and Freundlich models were applied to describe equilibrium isotherms and both models fitted well. The monolayer adsorption capacity was found as 31.75mg/g at pH 5 and 20°C. Dubinin–Radushkevich (D–R) isotherm model was also applied to the equilibrium data. The mean free energy of adsorption (13.78kJ/mol) indicated that the adsorption of Pb(II) onto kaolinite clay may be carried out via chemical ion-exchange mechanism. Thermodynamic parameters, free energy (ΔG°), enthalpy (ΔH°) and entropy (ΔS°) of adsorption were also calculated. These parameters showed that the adsorption of Pb(II) onto kaolinite clay was feasible, spontaneous and exothermic process in nature. Furthermore, the Lagergren-first-order, pseudo-second-order and the intraparticle diffusion models were used to describe the kinetic data. The experimental data fitted well the pseudo-second-order kinetics. [Copyright &y& Elsevier]

This paper presents the equilibrium and thermodynamic parameters of the adsorption of stearic acid on Celtek clay as a function of temperature. It was found that the adsorption of stearic acid on Celtek clay decreased with increasing temperature from 293 to 313 K. The equilibrium modelled data fitted well with the linear forms of both the Langmuir and the Freundlich models (R² = 0.99 in both cases). The RL and 1/n values determined from the isotherm models proved that Celtek clay is a suitable adsorbent for stearic acid. The Dubinin-Radushkevich (D-R) isotherm was applied to describe the nature of the adsorption of stearic acid on Celtek clay and it was found that the adsorption occurred physically. Thermodynamic parameters of adsorption, such as Gibbs free energy change (ΔG0), enthalpy change (ΔH0) and enthropy change (ΔS0) were also calculated. These parameters showed that the adsorption of stearic acid on Celtek clay was feasible, spontaneous, and exothermic in nature. On the basis of the results, it can be concluded that Celtek clay has considerable potential for the removal of stearic acid from the main sources, such as raw and edible soybean, sunflower and olive oils. [ABSTRACT FROM AUTHOR]

Abstract: Built in storage solar water heaters (BSSWHs) have been recognized for their more compact constructions and faster solar gain than conventional solar water heaters, however, their water temperatures quickly go down during the cooling period. A trapezoidal BSSWH without PCM storage unit was used as the control heater (reference) to investigate the effect of two differently configured PCM storage units on the temperature distributions in water tanks. In the first design, myristic acid was filled into the PCM storage tank, which also served as an absorbing plate. In the second design, lauric acid was filled into the PCM storage tank, which also served as a baffle plate. The water temperature changes were followed by five thermocouples placed evenly and longitudinally into each of the three BSSWHs. The effects of the PCMs on the water temperature distributions depended on the configuration of the PCM storage unit and the longitudinal position in the water tanks. The use of lauric acid lowered the values of the peak temperatures by 15% compared to the control heater at the upper portion of the water tanks because of the low melting temperature of lauric acid, but it did not have any consistent effect on the retention of the water temperatures during the cooling period. The ability of the myristic acid storage unit to retain the water temperatures got more remarkable, especially at the middle portion of the water tank. The myristic acid storage increased the dip temperatures by approximately 8.8% compared to the control heater. In conclusion, lauric acid storage can be used to stabilize the water temperature during the day time, while the myristic acid storage unit can be used as a thermal barrier against heat loss during the night time because of its relatively high melting temperature and low heat conduction coefficient in its solid phase. The experimental results have also indicated that the thermal characteristics of the PCM and the configuration of the PCM storage unit can result in advantageous control of the water temperature rise and drop during both day and night time. [Copyright &y& Elsevier]

Abstract: Adsorption equilibrium of stearic acid onto natural bentonite with Turkish origin was studied at the temperatures of 298, 308 and 318K. SEM and XRD analysis show that the bentonite used as adsorbent is composed of microcrystal and porous structure. The specific surface area was determined by BET method as 38.6m2/g. The adsorption of stearic acid onto bentonite was conformed to the Langmiur and Freundlich isotherms. The equilibrium parameter, R L revealed that the bentonite is a good adsorbent for stearic acid. The sorption capacity of bentonite studied decreases with increasing temperature. However, it is concluded that the adsorption capacity of bentonite for the stearic acid under the same experimental conditions is in comparable level in terms of that of the rice husk ash given in literature. Thermodynamic parameters, , was calculated to be between −21.8 and −22.8kJmol−1. and were found to be −9.2kJmol−1 and 42.4Jmol−1 K−1, respectively. These parameters obtained as a function of temperature indicate that the adsorption of stearic acid onto bentonite was a spontaneous and an exothermic process. An FT-IR study on the adsorbed material was used to verify the interaction of the stearic molecule with bentonite after adsorption process. [Copyright &y& Elsevier]

Thermal energy storage performance of fatty acids and a eutectic mixture as phase change materials (PCMs) has been investigated experimentally. The selected PCMs for this study were palmitic acid, myristic acid, stearic acid, and a mixture of stearic and myristic acids in eutectic combination ratio of 65.7 wt% myristic acid and 34.3 wt% stearic acid. The PCMs have a melting temperature range of 50.0°C to 61.20°C and a latent heat range of 162.0 J/g to 204.5 J/g. The inlet temperature and the mass flow rate of heat transfer fluid (HTF) were selected as experimental parameters to test the thermal energy storage performance of the PCMs. The transition times, temperature range, propagation of the solid-liquid interface, as well as heat flow rate characteristics of the employed cylindrical tube storage system were studied at varied experimental parameters. The experimental results show that the melting front moves to inward in the radial directions as well as in the axial directions from the top toward to the bottom of the PCM tube. It was observed that the convection heat transfer in the liquid phase plays an important role in the melting process. The changes in the studied HTF parameters have more effect on the melting processes than the solidification processes of the PCMs. The average heat storage efficiency calculated from data for all the PCMs is 51.5%, meaning that 48.5% of the heat actually was lost somewhere. [ABSTRACT FROM AUTHOR]

Renewable energy is proving to be commercially viable for a growing list of consumers and uses. Renewable energy technologies provide many benefits that go well beyond energy alone. More and more, renewable energies are contributing to the three pillars of sustainable development not only in IEA countries, but globally. Turkey is an energy-importing country; more than half of the energy requirement has been supplied by imports. Domestic oil and lignite reserves are limited and lignites are characterized by high ash, sulfur, and moisture content. In this regard, renewable energy resources appear to be one of the most efficient and effective solutions for sustainable energy development in Turkey. Turkey's geographical location has several advantages for the extensive use of most of these renewable energy sources. Because of this and the fact that it has limited fossil fuel resources, a gradual shift from fossil fuels to renewables seems to be serious and the sole alternative for Turkey. This article presents the role of the renewables in future directions in IEA countries with Turkey. At present the share of hydropower and biomass is high as 30% in the primary energy production of Turkey. In the case of solar, geothermal, and wind energy, there is an important potential for domestic heating and electricity generation. [ABSTRACT FROM AUTHOR]

Palmitic acid (PA, 59.8°C) and lauric acid (LA, 42.6°C) are phase change materials (PCM) having quite high melting temperatures which can limit their use in low temperature solar applications such as solar space heating and greenhouse heating. However, their melting temperatures can be tailored to appropriate value by preparing a eutectic mixture of the lauric and the palmitic acids. In the present study, the thermal analysis based on differential scanning calorimetry (DSC) technique shows that the mixture of 69.0wt% LA and 31wt% PA forms a eutectic mixture having melting temperature of 35.2°C and the latent heat of fusion of 166.3Jg-1. This study also considers the experimental determination of the thermal characteristics of the eutectic mixture during the heat charging and discharging processes. Radial and axial temperature distribution, heat transfer coefficient between the heat transfer fluid (HTF) pipe and the PCM, heat recovery rate and heat charging and discharging fractions were experimentally established employing a vertical concentric pipe-in-pipe energy storage system. The changes of these characteristics were evaluated with respect to the effect of inlet HTF temperature and mass flow rate. The DSC thermal analysis and the experimental results indicate that the LA–PA eutectic mixture can be a potential material for low temperature thermal energy storage applications in terms of its thermo-physical and thermal characteristics. [Copyright &y& Elsevier]

The phase change and heat transfer characteristics of a eutectic mixture of palmitic and stearic acids as phase change material (PCM) during the melting and solidification processes were determined experimentally in a vertical two concentric pipes energy storage system. This study deals with three important subjects. First is determination of the eutectic composition ratio of the palmitic acid (PA) and stearic acid (SA) binary system and measurement of its thermophysical properties by differential scanning calorimetry (DSC). Second is establishment of the phase transition characteristics of the mixture, such as the total melting and solidification temperatures and times, the heat transfer modes in the melted and solidified PCM and the effect of Reynolds and Stefan numbers as initial heat transfer fluid (HTF) conditions on the phase transition behaviors. Third is calculation of the heat transfer coefficients between the outside wall of the HTF pipe and the PCM, the heat recovery rates and heat fractions during the phase change processes of the mixture and also discussion of the effect of the inlet HTF parameters on these characteristics. The DSC results showed that the PA–SA binary system in the mixture ratio of 64.2:35.8 wt% forms a eutectic, which melts at 52.3 °C and has a latent heat of 181.7 J g−1, and thus, these properties make it a suitable PCM for passive solar space heating and domestic water heating applications with respect to climate conditions. The experimental results also indicated that the eutectic mixture of PA–SA encapsulated in the annulus of concentric double pipes has good phase change and heat transfer characteristics during the melting and solidification processes, and it is an attractive candidate as a potential PCM for heat storage in latent heat thermal energy storage systems. [Copyright &y& Elsevier]

Thermal performance characteristics of a eutectic mixture of lauric and stearic acids as phase change material (PCM) during the melting and solidification processes were determined experimentally in a vertical two concentric pipe-energy storage system. This study deals with three important subjects: The first one is to determine the eutectic composition ratio of the lauric acid (LA) and stearic acid (SA) binary system, and to measure its thermophysical properties by DSC. The second one is to establish the thermal characteristics of the mixture such as total melting and solidification times, the heat transfer modes in melted and solidified PCM, and the effect of Reynolds and Stefan numbers as inlet heat transfer fluid (HTF) conditions on the phase transition behaviors. The final one includes the calculations of the heat transfer coefficients between the outside wall of the HTF pipe and the PCM, and heat fractions during the melting and solidification processes of the mixture, and also the discussion of the effect of inlet HTF parameters on these characteristics. The LA–SA binary system in the mixture ratio of 75.5:24.5 wt % forms a eutectic, which melts at 37°C and has a latent heat of 182.7 J g−1, and, thus, these properties make it an attractive phase change material used for passive solar space heating applications such as building and greenhouse heating with respect to the climate conditions. The experimental results indicated that the mixture encapsulated in the annulus of two concentric pipes has good thermal and heat transfer characteristics during the melting and solidification processes, and it has potential for heat storage in passive solar space heating systems. [ABSTRACT FROM AUTHOR]

Experimental investigation of palmitic acid as a phase change material (PCM) for energy storage has been conducted in this study. The performance and heat transfer characteristics of a simple tube-in-tube heat exchanger system were studied, and the obtained results were compared with other studies given in the literature. The present study included some parameters, such as transition times, temperature range and propagation of the solid–liquid interface, as well as the heat flow rate characteristics of the employed cylindrical tube storage system. The experimental results show that the melting front moves in the radial direction inward, as well as in the axial direction from the top toward the bottom of the PCM tube. It was observed that the convection heat transfer in the liquid phase plays an important role in the melting process. The flow rate and inlet temperature of the heat transfer fluid to the PCM tube in the experimented range has an insignificant effect on the phase change processes. On the other hand, the melting and solidification times of the PCM can be reduced significantly by placing the tube containing the PCM in a horizontal position rather than a vertical one. The heat storage capacity of the PCM tube is not as good as we expected in this study, and the average heat storage efficiency (or heat exchanger effectiveness) is 53.3. It means that 46.7% of the heat actually is lost somewhere. [Copyright &y& Elsevier]

Focuses on a study that evaluated the thermal performance and phase change stability of stearic acid as a latent energy storage material. Background on several ways of storing thermal energy; Methodology; Results and discussion.

In this manuscript, the innovative design of a hybrid system is investigated for distilled water and hot water production using the heat pipe-equipped vacuum tube collector system assimilated with solar still (HTP-ETCS-SS). The proposed hybrid system is compared with traditional solar still (SS) in context of energy, exergy and financial analysis with two different depths, i.e., 40%, and 60%, and varying flow rate (4, 8, and 12 LPH). The results show a rise in distilled water productivity by 152.9%, 108%, and 51.9% with 40% depth and 162%, 152.5%, and 92.3% with 60% depth with a varying flow rate of 4, 8, and 12 LPH, respectively, in contrast to traditional solar still. The improvement in energy and exergy efficiency for distilled water output is gained between 40–22.2% and 0.7–4.1%, respectively, with the designed system. However, the system's energy and exergy efficiency lie between 64.8–42.4% and 28.4–16.4%, respectively, for both distilled water and hot water productivity. The 8 LPH flow rate is found optimum in terms of distilled productivity and hot water production. The designed system's distilled water and hot water unit costs are 0.1037$ and 0.0276$, respectively. [ABSTRACT FROM AUTHOR]

Background/aim: The main purpose of our study was to determine the efficacy of chemical shift imaging (CSI) for differentiating diffuse red bone marrow reconversion (RBMR) and hematological malignancies. We also aimed to calculate the cut-off value for these entities with similar imaging features in routine magnetic resonance (MR) sequences. Materials and methods: A total of 54 patients were included: 17 patients (31.4%) with hematological malignancies (group 1), 16 patients (29.6%) with RBMR (group 2), and 21 patients (38.0%) with no clinical and hematological malignancies (control group). Patients with no pathological data or completed two-year follow-up and children were excluded from the study. An experienced radiologist on MRI evaluated the images blindly for final diagnosis. Pathologic results were determined as gold standard. Regions of interests (ROI) were placed on the vertebrae in CSI and signal intensity ratios (SIR) were calculated. The cut-off value was calculated using receiver operating characteristic (ROC) analysis. Results: SIR values were 0.97 ± 0.16, 0.69 ± 0.31 and 0.28 ± 0.35 (P < 0.001) for GI, G2, and G3, respectively. The cut-off value was 0.82 (P < 0.001). The sensitivity rate was 83.3% (AUC: 58%-96%), specificity was 87% (AUC: 58-98). Conclusion: CSI may be a valuable diagnostic tool for differentiating diffuse RBMR and hematological malignancies. [ABSTRACT FROM AUTHOR]

The overheating of heat pipes, poor transfer of heat across the absorber and finned heat pipes, and inability to provide hot water in the late evening hours are major problems associated with conventional heat pipe vacuum collector systems. The amalgamation of highly conductive storage material between the absorber tube (heat collecting surface) and the heat pipe is an effective way to overcome these problems. In this study, a stearic acid amalgamated vacuum tube solar collector system was designed and fabricated and its thermal output compared with a conventional vacuum tube system without storage material under the same environmental conditions. The experimental results showed that the amalgamation of stearic acid as storage material enhanced the thermal output of the solar system compared to the conventional one. The desired heat gain of the solar system with storage material increased by 31.30, 23.34, and 18.78% for Test 1_40 °C, Test 2_45 °C, and Test 3_50 °C, respectively. The technoeconomic analysis showed that almost 118.80 USD in revenue could be earned by the proposed solar system at the end of 15 years. The total running cost of ELG and the developed solar system was observed to be 202.62 and 86.70 USD, respectively. On average, the cost of hot water production using the solar system and ELG was found to be 0.0016 and 0.004 USD/L, respectively. The value of LEC was found to be 0.062 USD/electricity unit, which was much lower than the LEC value of ELG (0.116 USD/electricity unit). The value of NPW (73.73 USD) indicated high acceptability of the proposed system. The payback time is lower than the life of the system, indicating its suitability for use in the commercial sector. Therefore, the proposed solar system is highly recommended over conventional water heating systems in urban and rural areas. [ABSTRACT FROM AUTHOR]

The world's annual powder traders expected to reach a figure of 13.20 MT by the end of 2024; expanding at a growth rate higher than 4% during the period 2019–2024. Also, skim / whole milk powder production recorded a steep rise of 50% in last three decades. In view of energy-intensive operations associated with milk powder production activity; it's imperative to perform economic assessment of milk powder production units on qualitative basis. In this paper, the thorough exergoeconomic examination of single stage, two stages, and three stages spray drying has been performed so as to present the outcomes in the form of cost rate associated with exergy destruction, exergoeconomic factor for each of the subunits, total operational cost rate and specific manufacturing costs etc. The cost rate associated with exergy destruction (Rs. hr−1) for each of the above-mentioned drying techniques were ascertained as 13,662.69, 26,244.46 and 3552.84respectively. Similarly, total operational cost rate (Rs. hr−1) were computed as 14,020.18, 26,835.88 and 3681.87 respectively. Further, specific manufacturing cost (Rs. kg−1) pertaining to skim milk powder production was found out to be 7.23, 13.80 and 29.22 respectively. Additionally, a comparative assessment of exergy and exergoeconomic entities is also presented in this paper. [ABSTRACT FROM AUTHOR]

Fossil fuels are sharing a large portion of energy demand. Conventional energy sources emit a huge amount of greenhouse gas into the atmosphere, which creates energy and environmental challenges for the ecosystem. To fulfill the world energy demand and to support environmental as well as economic development in a sustainable way, with the utilization of technological advancement of renewable energy resources, algae are presently believed as most adaptable feedstock materials for bioenergy production. Algae has a high fixation rate of atmospheric carbon dioxide which supports to fast growth rate with high productivity per unit area in the form of renewable algal biomass. The present article aims to elaborate on the three generations of biofuels, sustainable microalgae biomass production, cultivation systems, and a wide range of growth parameters. The microalgae harvesting methods and their challenges are also discussed, with a special focus on lipid extraction methods and future r recommendations. The upstream and downstream processes of microalgae could help to harness the microalgae energy in an eco-friendly manner and will help in achieving overall sustainable development. • Microalgal biomass is a sustainable feedstock for biofuel and bioproducts. • Optimization of upstream and downstream processes enhance produces of microalgae. • Important biotic and abiotic factors of microalgae cultivation are summarized. • Critical steps of harvesting and transesterification of microalgal are discussed. • The key challenges with future recommendations of algal cultivation are briefed. [ABSTRACT FROM AUTHOR]

The foremost challenges in heat pipe ETC are low heat transfer rate between absorber tube & heat pipe, overheating of heat pipes, and its inability to supply hot water during off-pick hours. The incorporation of latent heat storage material (LHSM) between absorber tube and heat pipe is the efficient solution to overcome these challenges. Also, along with energy and exergy analysis, economic & environmental analysis to be done to ensure whether utilization of LHSM with ETC system is viable for the commercial utility. Thereby, in this study, energy, exergy, economic & environmental analysis of stearic acid integrated ETC for two different modes (ETC/Mode-I & II) have been done and distinctly in comparison to the reference system. The daily energy efficiency of ETC/SA for ETC/Mode-I and ETC/Mode-II improved by 37–45 and 65–81% respectively, whereas, improvement in exergy efficiency was observed by 21–29 and 57–73% respectively. The positive value of NPV shows that investment in ETC/SA will be highly profitable. The ETC/SA mitigated CO 2 emission in the range of 26–37 and 8–12 tCO 2 /lifetime based on energy and exergy approach respectively. Thus, ETC/SA working for ETC/Mode-II system was found to be more economical, highly energetic & exergetic efficient, and more environmentally friendly. [ABSTRACT FROM AUTHOR]

The integration of phase change materials (PCM) into architectural elements is an emerging strategy to enhance thermal energy storage in modern buildings. This research examines 3D-printed polylactic acid structures incorporated with microencapsulated PCM, targeting a more efficient thermoregulation in foundational architectural sections such as walls, floors, and ceilings. Through rigorous evaluations, the polylactic acid-PCM composite revealed promising thermoregulatory properties. Notably, latent heat values stood at 198.4 J/g for melting and 197.9 J/g for freezing. Real-world experiments demonstrated a distinct advantage, maintaining temperatures 3.2°C–3.3 °C higher than standard polylactic acid at night and exhibiting a cooler range of 10.4 °C–13.3 °C during daylight. Within specific geographical contexts, like the Mediterranean and Aegean Seas coastline, 0.026 m thick polylactic acid-PCM panels stood out, registering 100 % energy savings. The findings consistently showed that an increase in panel thickness correlated with a decrease in building heating needs. Further analysis explored the carbon emissions landscape. Coal, when utilized with 0.05 m-thick polylactic acid-PCM panels, was identified as particularly effective, yielding a reduction of 34 kg/m2 in annual CO 2 emissions. Collectively, the findings underscore the transformative potential of polylactic acid-PCM composites, positioning them as pivotal tools for advancing architectural energy efficiency and fostering sustainable building innovations. [Display omitted] • MPCM successfully embedded into 3DP polylactic acid structures for enhanced thermoregulation. • PLA-PCM composites outperform pure PLA in temperature regulation. • Composite's performance varies with regional climate conditions. • Different heating needs suggest thickness customization per region. • PLA-PCM panels, combined with fuels like coal, resulted in significant CO2 savings. [ABSTRACT FROM AUTHOR]

Open sewage contaminated channel wastewater (OSCCW) has high pollutant loads, responsible for eutrophication, when mixed with various channels of urban communities. But, these pollutants can be converted and recovered into useful end products with the help of algal species. In this study, two species of Chlorella (C. vulgaris and C. pyrenoidosa) were selected and investigated for the production of algal biomass and nutrient removal efficiencies with 50% concentration of OSCCW, in a comparative way at lab-scale. Chlorella sp. cultivated in OSCCW have removed nitrate (76.9–78.8%) and phosphate (67.6–79.7%) whereas COD (72.4–76.2%) and BOD (62.3–72.4%) respectively. Correlation analysis was investigated between physico-chemical parameters and biochemical profile of both species to analyze the positive and negative correlation between two variables. The bio-chemical profile and biomass productivity of both species of Chlorella were observed well on the basis of productivity of biomass (60.1, 56.5 mg/l/d), carbohydrate (15.71, 8.82 mg/l/d), protein (11.21, 15.82 mg/l/d), lipid (20.8, 17.5 mg/l/d) and chlorophyll (0.78, 0.67 mg/l/d) in OSCCW. The maximum lipid content (34.6%) was obtained with C. pyrenoidosa as compared to C. vulgaris. Findings also support that OSCCW is well-off with nutrient resources, which can be suitable alternative for algal biomass production and remediated wastewater can be used for animal and fish farming type activities. [Display omitted] • Chlorella sp. are used to treat open sewage contaminated channel wastewater (OSCCW). • Nutrients and pollutants in OSCCW have been investigated for dual benefits. • Maximum resource recovery is observed from OSCCW. • C. pyrenoidosa produced the highest 34.6% lipid in 50% of OSCCW. • Correlation analyzed between biochemical profile of algae and parameter of OSCCW. [ABSTRACT FROM AUTHOR]

Corn drying is an energy-intensive process. Thus, the management of energy use is critical for economical corn drying. The Central Black Sea Region covering Amasya, Çorum, Ordu, Samsun and Tokat provinces has climatic and agronomic conditions suitable for corn production. However, the drying of newly harvested wet corn stays as a major problem lot farmers since it is traditionally dried by spreading it on the ground in open atmosphere. Low temperature drying was selected in this computational study to dry corn safely. Fan power, heating power, total electric energy need of fan and total heating energy needed and to dry 1 ton corn from 25% (wb) initial moisture content to 13% (wb) final moisture content were estimated in September, October and November for each province. The airflow requirements (i.e., 159.1 m³·ton-1·h-1 for Amasya) and overall electric energy needs of selected fans (i.e., 27245 kJ·ton-1 for Amasya) in September are more than in November (68.3 m³·ton-1·h-1 and 10221 kJ·ton-1, respectively) because of quick deterioration of wet corn associated with high air temperatures in September. On the other hand, heating power requirements showed a mixed trend while the total heating energy needs consistently increased for all provinces when the drying operation was moved from September to November. In conclusion, the estimated total heating need increased while the estimated total electric energy need of fan decreased since the heating process increased the adiabatic drying potential of air, which in turn reduced the amount of air volume having to he flown through corn in the drying bin. [ABSTRACT FROM AUTHOR]

Background/aim: To evaluate diagnostic efficacy of the apparent diffusion coefficient measurements from tumor (ADCt) and tumor circumference hyperintensities (ADCtch) in different types of malignant intra-axial brain tumors. Materials and methods: Between April 2013 and June 2017, 125 patients (52 females (41.6%) and 73 males (58.4%); mean age: 53 years, age range: 14-81 years), who underwent diffusion-weighted imaging (DWI) with intracranial mass, were retrospectively evaluated. The mean ADCt and ADCtch values and ratios were measured. Results: Of the 125 patients, 22 (17.6%) had a low-grade glioma (LGG), 55 (44%) had a high-grade glioma (HGG), 32 (25.6%) had metastasis, and 16 (12.8%) had lymphoma diagnosis. There was a statistically significant difference in LGG and HGG in terms of mean ADCt and mean ADCtch values, and ratios. ADCtch values and ratios showed a statistically significant difference in the differentiation of HGG and metastasis and in the differentiation of HGG and lymphoma. According to ROC curve analysis, a cut-off value of 1.49 x 10--3 mm2/s for the mean ADCtch value generated the best combination of 70% sensitivity and 71% specificity for differentiation of HGGs and metastasis. The mean ADCtch value had the highest statistical predictive value for differentiation of HGGs and lymphoma with a sensitivity of 78% and a specificity of 76% for the optimal cut-off value of 0.82 x 10--3 mm²/s. Conclusion: The mean ADCt ratio allowed reliable differentiation of LGG and high grade brain tumors, including HGGs, metastases, and lymphoma. The mean ADCtch might be a better imaging biomarker in the differentiation of HHG from metastasis and lymphoma. [ABSTRACT FROM AUTHOR]

Objective: In this retrospective study, we assessed if the admission levels of interleukin (IL)-6 and other inflammatory parameters corralate with the extension of lung involvement on computed tomography (CT) in severe-critical COVID patients. Materials and Methods: Ninety patients with a diagnosis of COVID-19 in the intensive care unit were included; however, 30 of these patients who were diagnosed as COVID-19 [polymerase chain reaction (PCR), CT, or history-clinical presentation-laboratory] and whose CT and IL-6 inflamatory parameter results could be obtained were finally analyzed. Admission CT scan findings were analyzed according to a 40-point system, and compared to the admission levels of plasma IL-6 as well as c-reactive protein, procalcitonin, lymphocyte, and neutrophyl/lymphocyte ratios. Results: No correlation was found between the IL-6 levels and CT scores taken in the same time period. IL-6 levels were corraleted with procalcitonin levels and mortality rate ssuggesting that bacterial infections were supervened on the clinical scene of these patients. Conclusion: In our study, we could not show any correlation between CT scores and an elevation of IL-6 levels. The role of the cytokine storm in COVID-19 pneumonia that manifests with cell death, thrombotic sequences, and alveolar edema might be explained by ongoing studies. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to determine the differences and consistencies in the morphological and angular interpretations of standard USG images. Therefore, it was aimed to show the correlations of orthopaedic doctors with different periods of experience in hip ultrasound measurements taken with the Graf method. Materials and methods: The study included 210 infants randomly selected from those who presented at our hospital for DDH screening. A total of 6 ultrasound images were taken for each hip. These images were evaluated by two paediatric orthopaedic professors, two orthopaedic specialists and two orthopaedic residents. The correlations of these measurements between all the doctors were evaluated statistically. Results: In beta angle evaluation, agreement between all the evaluators was at the level of 0.054. No agreement was seen between the two residents or between the two specialists (p = 0.003, p = 0.998, p = 0.998, respectively). Agreement between the two professors was determined at the level of 0.508 (p < 0.001). Agreement was determined at the level of 0.066 between the specialists and the residents. No agreement was observed between the specialists and the professors or between the professors and the residents (p = 0.014, p = 0.098, p = 0.737, respectively). Conclusions: It can be concluded that greater emphasis on the beta angle, the cartilage labrum, and more detailed explanations of this subject in the resident training program will achieve standardisation on this subject, and this is in direct proportion to clinical experience. Level of evidence: IV [ABSTRACT FROM AUTHOR]

Highlights • ETC and ETC-HP system is discussed with possible applications. • Performance of heat pipe ETC is higher compared to direct flow ETC. • PCMs application in ETC system proves it more efficient as compared to without PCM. • Heat Pipe ETC found more suitable for industrial/domestic applications. • Thermal Analysis of ETC-HP and direct flow ETC is discussed. Abstract Sun is the prime source of energy. There are two types of technologies available for the harnessing of solar energy i.e. Solar Thermal and Solar photovoltaic. Solar thermal energy having a potential to provide the domestic and industrial energy demand for hot water, air heating, solar cooling, solar drying etc. Among multiple applications of solar energy, water heating, space heating, and cooling are consuming more energy. The energy consumption in production of hot water represents a large contribution of total building energy consumption. The Collector is the important aspect for efficient energy needs for these applications. Among all thermal collectors specifically for low/medium temperature applications, evacuated tube collector is found to have the best efficiency. This paper addresses the advancement, different types of evacuated tube collectors and its low/medium temperature applications. The use of heat pipe in evacuated tube has been studied by many researchers around the globe to overcome the lower performance issue in direct flow evacuated tube collector. This turns out to be one of the most important advancement in this area. Another, important advancements in this research have been found to be integration of phase change materials with evacuated tube collector which has the great impact on its performance. This makes the evacuated tube technology more efficient, reliable and user-friendly. This review covers the recent research areas of the direct flow and heat pipe evacuated tube collector with different applications and comprehensive knowledge of the theoretical analysis. This paper also provides financial advantages, classification with and without thermal energy storage, advantages and drawbacks of evacuated technology and future recommendation for future improvement and recent research trend have also incorporated in this manuscript for researchers and practice engineers. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) can be applied to several different solar energy systems for the extended heat energy storage which is quite useful as the solar energy is intermittent in nature and is unavailable during the night period. Application of PCMs in solar energy systems allows the solar energy to be used at any time even in the absence of the natural solar radiation. Thus, the use of PCMs in the solar energy systems can bridge the demand and supply gap of the normal electrical energy. This paper deals with the recent advances in PCMs application in different solar energy systems and presents almost all of the emerging areas where the applications of PCM in solar energy systems are urgently required. The novel and most recent developments of PCMs in solar thermal energy systems, such as, solar thermal power plants, solar air heater, solar water heater and solar cooker have been duly covered. Furthermore, the application of PCMs in heating and cooling of buildings have been presented as well as the investigation of the PCM application in the solar photovoltaic systems for the performance enhancement of PCMs. Intrinsically important, from the study it has been found that PCMs have been in use in almost all of the solar energy systems even though their uses are still limited and commercially not available due to several economic and environmental constraints. Thus, the paper attempts to present recent and novel approaches by the authors around the world on PCMs applications in the solar energy in well documented forms. Based on the findings, future recommendations have also been given to provide the idea and pragmatic concepts for the researcher to work on the areas of research for further improvements in the systems. [ABSTRACT FROM AUTHOR]

Giant cell tumors (GCTs) are usually found in the epiphysis of the long bones, and represent ~5% of all bone tumors. Only <1% of GCTs are localized in the cranium. When localized in the cranium, GCTs are commonly observed in the sphenoid or temporal bones, and rarely in the parietal or frontal bones. Occipital bone posterior fossa involvement is an extremely rare occurrence. The current study presents a 22-year-old female patient was admitted to the Department of Radiation Oncology (Karadeniz Technical University, Faculty of Medicine, Trabzon, Turkey) with complaints of neck pain and headache. The patients cranial magnetic resonance images showed a 2.5 6-cm mass in the occipital bone, which was subtotally excised. The patient was treated with radiotherapy following the surgery. At present, the patient has shown no progression after 20 months of follow-up. [ABSTRACT FROM AUTHOR]

Giriş: Yüzyıl önce Kraepelin, şizofreninin ayırt edici özelliğinin, ilerleyici olarakkötüleşme göstermesi olduğunu belirtmiştir. Şizofrenide Kraepelin ölçütleribeş yıl boyunca (i) sürekli hastane yatış hikâyesi, yatmayanlarda günlük yaşamaktivitelerinde başkasına tam bağımlılık, (ii) gerçek bir iş edineme ve (iii) tamdüzelmenin yakalanamaması olarak tanımlanmıştır. Bu araştırmada Kraepelinölçütlerini karşılayan şizofreni hastalarının klinik görünümleri ve yapısal biyolojiközelliklerinin Kraepelin ölçütlerini karşılamayan şizofreni hastaları ve sağlıklıkontrollerle karşılaştırılması amaçlanmıştır.Yöntemler:Kraepelin ölçütlerini karşılayan 17 ve bu ölçütlerin dışında kalan 30şizofreni hastası ile 43 sağlıklı birey örneklemi oluşturdu. Klinik özellikler KlinikGlobal İzlenim (KGİ) Ölçeği, Pozitif ve Negatif Sendrom Ölçeği (PANSS) ile bilişselişlevler Frontal Değerlendirme Bataryası (FDB), Sözel Akıcılık (SA) ve Renk İzlemeTestleri (RİT) ile değerlendirildi. Yapısal özelliklerin değerlendirilmesinde beyninmanyetik rezonans (MR) görüntülemesi ve dermatoglifik değerlendirilmesi yapıldı.Bulgular:Şizofreni grupları arasında hastalık süresi, yatış öyküsü, intihar öyküsü,geliş şekli, stresör varlığı, tedavi açısından farklılık yoktu. Kraepelin ölçütlerinikarşılayan şizofreni hastalarında aile öyküsü ve ilaca yanıtsızlık daha yüksek orandasaptandı. Kraepelin ölçütlerini karşılayan şizofreni hastalarında PANSS’ın tüm altölçekleri ve KGİ puanları daha yüksekti. Kraepelin ölçütlerini karşılayan grubundiğer şizofreni hastalarına göre bilişsel işlevlerden yalnızca kategori akıcılığında veRİT-I’de farklılık gösterdiği saptandı. Üç grup arasında MR ve dermatoglifik ölçümdeğerleri açısından istatistiksel olarak anlamlı fark belirlenmedi.Sonuç:Kraepelin ölçütlerini karşılayan şizofreni grubunda performansın düşüksaptandığı kategori akıcılığı, dejeneratif süreçlerde önemli bir gösterge kabuledilmektedir. Şiddetli klinik belirtiler, ailesel özellik ve tedaviye yanıtsızlığın bu gruptatoplanması gelecekte küme analizini içeren bir yöntem ile çalışmalar yapılmasıgereğine işaret etmektedir. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electric geyser waste material deposit (EGWMD) was used for flocculation of microalgae. • Poultry excreta leachate used as nutrient medium for biomass growth. • Flocculation efficiency was optimized at 98.21%. • The reusability of spent medium is obtained at 70.2% and 32.5%. • Waste valorization with reutilization is a sustainable harvesting process. The aim of this work was to study the flocculation efficiency of algal biomass (Chlorella pyrenoidosa) in coupling with waste materials i.e. poultry excreta leachate by using other waste material which was obtained from deposition of scaling in electric geyser. Utilization of electric geyser waste material deposit (EGWMD) for flocculation is a novel approach because of various elements which are replica of chemical flocculants responsible for flocculation mechanism in culture medium. Flocculation process was optimized by response surface methodology and 98.21% flocculation efficiency was achieved with designed process parameters as temperature 32.5 °C, flocculant dose 275 mgL-1, pH 5 and time 30 min. The reusability of spent medium was also analyzed at 70.2% and 32.5% flocculation efficiency with two successive steps. The cellular morphology of pre-harvested and post-harvested Chlorella pyrenoidosa was also observed. EGWMD is abundant and freely available that has no application till now and can alternate of chemical flocculants. [ABSTRACT FROM AUTHOR]

One of the feared complications during detachable coil embolization of cerebral aneurysms is herniation of a coil loop into the parent artery. Although coil protrusion of one or two loops into the parent vessel may not cause adverse events and in some instances can be ignored, the authors believe that coil retrieval is indicated if a free end is seen pulsating along the blood flow stream to prevent migration of the entire coil mass. In one patient, a microballoon was inflated across the neck of the aneurysm during retrieval of a herniated coil to prevent further coil herniation from the aneurysm sac. We present two cases in which prolapsed coils were successfully retrieved either using a microsnare and balloon combination or a microsnare alone. This report focuses on the efficacy of the Amplatz microsnare for such retrievals and the circumstances in which a herniated coil needs to be retrieved. We report two cases in which embolization coils partially migrated into the parent artery during endovascular treatment of cerebral aneurysm and were retrieved using the Amplatz Nitinol microsnare. [ABSTRACT FROM AUTHOR]

A case of pilocytic astrocytoma of neurohypophysis is presented. The clinical, pathological and MRI features of a rare tumor of the neurohypophysis are described. A 5-year-old girl presented with a 3 month history of lethargy, im-balance and visual disturbances. A MRI revealed a large suprasellar mass. Histopathological examination demonstrated a pilocytic astrocytoma. Its astrocytic nature was confirmed by positive immunostaining for GFAP and the findings of an electron microscopy. [ABSTRACT FROM AUTHOR]

In present work, techno-economic and thermodynamic analysis of an ETC with/without PCM has been undertaken. The results approved that for all selected flow rates, ETC/S obtained higher energy and exergy efficiencies in comparison to the ETC/WS design. The maximum attained value of average daily energy efficiency for ETC/S and ETC/WS was 78.36% and 54.10% respectively with a high flow rate (24 L/h). Also, at this flow rate, ETC/S and ETC/WS attained peak value of average daily exergy efficiency of 23.15% and 20.06% respectively. The average daily energy efficiency of ETC/S was found to be 53.46%, 30.87%, and 44.85% higher in comparison to ETC/WS for low (8 L/h), medium (16 L/h) and high (24 L/h) flow rate respectively. Hence, the integration of SA (stearic acid) as energy storage material with HP-ETC not only stored the thermal energy but also enhanced the system performance. Furthermore, the techno-economic study revealed that the cost of production of hot water by ETC/S has been found to be lowest compared with ETC/WS and electric geyser. This analysis showed that ETC/S system has a promising potential in terms of supply of hot water from low to medium temperature range at a cheaper rate at lower payback period. • Thermal performance of the developed systems is influenced by the flow rates. • Performance of evacuated tube collector with/without storage was investigated. • Economic viability of developed systems is done by techno-economic analysis. • HP-ETC with phase change material having good performance. [ABSTRACT FROM AUTHOR]

• The performance of evacuated tube collector with/without storage was investigated. • Evacuated tube collector with phase change material showed better performance. • Designed system is suitable for day/night time utilization of hot water. • Thermal cycle test of SA-67 has been studied for long term stability. This manuscript presents an experimental investigation of heat pipe evacuated tube solar collector with and without phase change material for water heating application under the same weather conditions. In this study, a comparative analysis of two systems has been done in the same weather condition. Where evacuated tubes of the first system (evacuated tube collector-A) were left without phase change material and second system (evacuated tube collector-B) was integrated with SA-67 as phase change material. In order to ensure the thermal and chemical stability of the selected phase change material, thermal cycling treatment was carried out. The results showed that SA-67 has excellent chemical and thermal stability even after 1500 thermal cycling treatment. In order to analyze the thermal performance of the designed systems, the experiment was conducted with five different water flow rates (8, 12, 16, 20 and 24 L per hour). The daily thermal efficiency of evacuated tube solar collector with and without phase change material was varied in the range of 42–55% and 79–87% respectively. Although, the daily energy efficiency of evacuated tube collector integrated with phase change material was 37.56%, 35.31%, 36.69%, 32.34%, and 32.73% higher than evacuated tube collector without phase change material for water flow rates of 8, 12, 16, 20 and 24 L per hour respectively. The daily thermal efficiency for both systems was maximum at the flow rate of 20 L per hour. The heat transfer parameters for the designed systems have also been evaluated and compared. [ABSTRACT FROM AUTHOR]

Summary Haemangiopericytoma (HPC) is a rare tumour of the cental nervous system. Previously, HPCs were thought to originate from meninges and ventricular walls. Currently, they are accepted as distinctive mesenchymal neoplasms unrelated to meningiomas. Imaging appearances, clinical progression and haemorrhage into a cystic tumour is documented in an 18-year-old man where the final diagnosis, with histopathological verification, proved to be a cystic HPC. This interesting and illustrative case is discussed with the relevant literature. [ABSTRACT FROM AUTHOR]