Daily Output Research Articles

On the performance of solar humidification-dehumidification desalination system with subsurface condenser

The solar humidification-dehumidification desalination system with a subsurface condenser is a promising and sustainable approach to providing a sustainable water supply. In this study, a comprehensive three-dimensional transient computational fluid dynamics model of the system is developed. Due to the lack of an experimental study on the thermal performance of the subsurface condenser, an experimental setup of the subsurface condenser is built, and the obtained experimental results are used to validate the developed model of the subsurface condenser. The developed numerical model is used to evaluate the effect of several involving parameters on the system performance. The optimum system parameters are determined, and the annual simulation of the optimum system is performed. The results show that condenser inlet velocity is the most influential parameter on daily water yield and Gain Output Ratio (GOR). The GOR of the system with the maximum daily water yield is very low. However, despite having 60% less daily water yield, the proposed optimum system has a 1120 % higher GOR. Moreover, it is demonstrated that about 40% of vapor produced in the humidifier leaves the condenser without being condensed into freshwater. Therefore, it is recommended that the system be designed as a closed cycle.

Novel techniques to enhance the performance of Stirling engines integrated with solar systems

In this paper, we present three novel techniques for enhancing Stirling engines (SE). Conventional SE regenerators are replaced with Phase-Change material (PCM) regenerators to increase regenerator and engine performance. The plate receiver of a Solar-Dish Stirling engine (SDSE) is replaced with a glass receiver to increase direct radiation absorption and reduce losses. An SDSE system is coupled with a PCM Thermal Storage Reservoir PCMTSR)) to store the rejected heat during daylight and extract stored energy to produce power during the night. Either ambient air or geothermal water is used to cool down the engine during night operation. Theoretical models were constructed to determine the effects of the proposed modifications on SE performance. Installing a PCM regenerator with 0.6 porosity and 10 mm length increased the regenerator effectiveness by 3.8% and the SE efficiency by 4.2%. However, high-porosity PCM regenerators suffered from engine frequency limitations: PCM regenerators with 0.9 porosity limited the SE to 12Hz. Installing a glass receiver in SDSE systems caused a 10% SE efficiency and a 37.9% system efficiency gain at 700 W/m2 solar radiation. An air-cooled SDSE-PCMTSR system produced 22.6% of the daily energy output during the night, while its geothermal-cooled counterpart produced 73% during the night.

Three-Dimensional Nanopillar Arrays-Based Efficient and Flexible Perovskite Solar Cells with Enhanced Stability.

Perovskite nanopillars (PNPs) are propitious candidates for solar irradiation harvesting and are potential alternatives to thin films in flexible photovoltaics. To realize efficient daily energy output, photovoltaics must absorb sunlight over a broad range of incident angles and wavelengths congruent with the solar spectrum. Herein, we report highly periodic three-dimensional (3D) PNP-based flexible photovoltaics possessing a core-shell structure. The vertically aligned PNP arrays demonstrate up to 95.70% and 75.10% absorption at peak and under an incident angle of 60°. The efficient absorption and the orthogonal carrier collection facilitate an external quantum efficiency of 84.0%-89.18% for broadband wavelength. PNPs have been successfully implemented in flexible solar cells. The porous alumina membrane protects PNPs against water and oxygen intrusion and thereby imparts robustness to photovoltaic devices. Meanwhile, the excellent tolerance to mechanical stress/strain enables our unique PNP-based device to provide efficient solar-to-electricity conversion while undergoing mechanical bending.

Design and implementation of an extensive-process method for improving the processing efficiency and capacity of the production logistics system

ABSTRACT Aiming at the low processing efficiency, low daily output, and long processing time of production logistics systems in small and medium-sized automobile enterprises, this study designed a novel production logistics system based on an extensive process. After improving the processing procedures, an extensive process method is adopted to classify product materials and number the process flow. Next, an automatic identification method for single and multi-process process changes is designed, and real-time control and feedback of the production process are realized. Finally, the design and implementation of the system structure and function are completed. The problem of chaotic and disorderly production in the workshop is solved, and the processing efficiency and daily output are improved. The efficiencies of the SVW Limit Arm (SVW) and FAW Limit Arm (FAW) increased by 37.33% and 39.85%, respectively. The daily output of the two products increased by 55.65% and 32.04%.

Hematopoietic Flt3+ Multipotent Progenitors Are Organized in Discrete Functionally and Hierarchically Distinct Populations

Blood production in the bone marrow (BM) is classically viewed as a constant hematopoietic flux originating from a small pool of self-renewing hematopoietic stem cells (HSCs). In this model, quiescent HSCs regularly differentiate and give rise to a complex set of transient multipotent progenitors (MPPs) that serve as compartments of amplification through division, while undergoing progressive lineage specification Recent studies exploiting sophisticated genetic marking for in vivo cell-fate tracking have challenged this paradigm and suggested that HSCs have a limited contribution to steady state blood production (Sun, Nature 2014, Busch, Nature 2015; Rodriguez-Fraticelli, Nature 2018). The interpretation of these results and the extent of the HSC contribution to native hematopoiesis remains a matter of debate (Pucella, Annu Rev Cell Dev Biol 2020; Rodriguez-Fraticelli, Curr. Opin. Hematol 2021). Beyond this debate, these studies have highlighted the underestimated contribution of the MPP compartment to the daily hematopoietic output in unperturbed conditions. This new understanding raises questions about the functional properties of the MPP compartment in steady state condition and its ability to independently sustain prolonged hematopoietic cell production. Here we revisited the early hematopoietic hierarchy present in the Lin- Kit+ Sca1+ (LSK) fraction that includes all HSC and MPP (MPP1-5) compartments. Highly-multiplexed CITE-Seq single cell analyses with over 60 antibodies identified a novel LSK CD62L- Flt3+ population (CD62L- MPP4) that clusters within the MPP compartments but displays a cell cycle gene signature similar to the one found in quiescent HSCs. Analysis of the Mki67 reporter mouse model and nucleotide analogue incorporation assays directly confirmed the existence of this unexpected cell cycle diversity in MPP4 during unperturbed hematopoiesis. Consistent with the molecular data, these analyses characterized a resting CD62L- and a proliferative CD62L+ MPP4 compartments. These two populations showed similar cloning efficiency in methylcellulose assays indicating that both populations behave as intermediary MPP compartments. When assessed in short-term culture, both populations were responsive to Flt3L stimulation but displayed specific kinetics of division. They also showed distinct short-term reconstitution ability upon transplantation in correlation with their cell cycle activity. Analysis of these populations in native condition using the H2B-GFP label-retaining system further confirmed the specific properties of the resting CD62L- MPP4 cells, distinct from the other proliferative MPP2, MPP3 and CD62L+ MPP4 compartments. Finally, these studies uncovered a novel early path of differentiation that involves the MPP5 cells (LSK Flt3+ CD48- CD150-) sequentially acquiring Flk2 and CD48 expression to generate the resting CD62L- MPP4 compartment, which in turn gives rise to cycling CD62L+ MPP4 cells. Altogether, these results challenge the accepted dichotomy between quiescent HSCs and dividing progenitors. While difference in lineage potential has been historically a major criterium to classify MPP populations, we established a new dimension at the MPP diversity, based on their proliferative activity at steady state. These results particularly highlight a new path of differentiation directly linking MPP5, a quiescent compartment with residual self-renewal capacity, to the resting CD62L- Flt3+ MPP cells. Based on these results, we proposed that slow-dividing Flt3+ MPPs act as a key transitional compartment that can buffer the hematopoietic cell production and therefore regulate hematopoietic homeostasis at steady state. We envision that this novel compartment could be a key intermediary for hematopoietic malignancies driven by the acquisition of Flt3 mutations and a cellular target for intervention.

Abstract 13972: Intermittent Occlusion of the Superior Vena Cava Improves Urine Sodium Excretion in Patients With Acutely Decompensated Heart Failure

BACKGROUND: Urine sodium excretion identifies risk for short and long-term adverse events in acutely decompensated heart failure (ADHF). The VENUS HF Early Feasibility Study is testing whether intermittent occlusion of the superior vena cava (SVC) with the preCARDIA system, a catheter mounted balloon and pump console, improves decongestion in ADHF. We hypothesized that preCARDIA therapy increases natriuresis in ADHF. Methods: In a multicenter, prospective, single-arm exploratory safety and feasibility trial, 32 patients with ADHF were assigned to preCARDIA therapy for 24 hours. Urine output and urine electrolytes were measured from a spot urine sample before, immediately after, and for 24 hours after preCARDIA treatment in 13 patients. Results: 32 patients were enrolled and received the preCARDIA system. Thirteen patients had complete urine electrolytes available for analysis. Compared to pre-treatment values, total daily urine output increased (1.9±0.8 vs. 4.2±1.5 L/day, p<0.001) and net fluid balance improved (-1.2±0.8 vs. -2.6±1.4 L/day, p=0.01) with treatment. Compared to pre-treatment, urine sodium (U-Na: 64±26 vs 97±24 mEq/L, p=0.0008) and U-Na/urine creatinine (U-Na/U-Cr: 1.7±1.3 vs 5.3±3.9 mmol/mg p=0.024) increased with treatment (Figure). Improved daily urine output and net fluid balance persisted 24 hours after treatment (1.9±0.8 vs 4.4±1.5 L p=0.0001; -1.2±0.8 vs -3.2±1.5 L/24h p=0.0003, respectively). Both U-Na and U-Na/U-Cr remained increased 24 hours after device removal (90 mEq/L, p=0.01; 3.93±2.8 p=0.026). Treatment increased fractional excretion of U-Na (2.08±1.87% vs. 4.22±2.72% p=0.05). No change in potassium excretion was observed. Conclusions: We report for the first time that intermittent SVC occlusion using the preCARDIA system to reduce congestion may increase urinary sodium excretion in ADHF. Future studies will further test the clinical utility of the preCARDIA system.

Abstract 14026: Intermittent Occlusion of the Superior Vena Cava Reduces Estimated Stressed Blood Volume in Patients With Acutely Decompensated Heart Failure

BACKGROUND: Stressed blood volume (SBV) refers to intravascular volume that produces hydrostatic pressure and contributes to congestion in acutely decompensated heart failure (ADHF). The VENUS HF Early Feasibility Study (EFS) is the first clinical trial testing intermittent occlusion of the superior vena cava (SVC) with the preCARDIA system, a catheter mounted balloon and pump console, to improve decongestion in ADHF. We hypothesized that preCARDIA therapy reduces SBV in ADHF. Methods: In a multicenter, prospective, single-arm exploratory safety and feasibility trial, 32 patients with ADHF were assigned to preCARDIA therapy for 24 hours. Invasive hemodynamics were measured before, immediately after, and for 3 hours after preCARDIA treatment. SBV was estimated (eSBV) using the hemodynamic simulator, Harvi, with heart rate (HR), cardiac output (CO), central venous pressure (CVP), pulmonary capillary wedge pressure (PCWP), systolic and diastolic systemic arterial and pulmonary artery (PA) pressures, and left ventricular ejection fraction (LVEF) from 27 enrolled subjects. Results: Mean LVEF was 28±13%. Freedom from device or procedure related major adverse events was observed in 96% (n=26/27) of patients. Compared to pre-treatment values, CVP, PCWP, and PA pressures were significantly reduced, while systemic mean arterial pressures, HR and CO remained unchanged (Table 1). Daily urine output (2.6±1.9 vs 5.2±3.8 L, p=0.0072) and net fluid balance (-1.7±1.4 vs -3.4±2.6 L/24hr, p=0.0098) improved with 24-hours of treatment. Compared to pre-treatment values, eSBV decreased by 22% or -709±551 mL/70kg from baseline to 3 hours after treatment completion (3217±426 vs 2507±694 mL/70kg, p<0.000001). Conclusions: We report for the first time that intermittent SVC occlusion using the preCARDIA system reduced estimated stressed blood volume in patients with ADHF. These results support future studies characterizing the clinical utility of the preCARDIA system.

LBMON140 Central Diabetes Insipidus Manifesting After Vasopressin Withdrawal In A Critically Ill Patient

Abstract Introduction Central diabetes insipidus is a rare clinical entity characterized by a lack of vasopressin secretion from the posterior pituitary. We present a case of central diabetes insipidus manifesting after the withdrawal of vasopressin in a critically ill patient. Case presentation A 19 year old female with a history of Hodgkin's Lymphoma treated with chemotherapy was transferred from another medical facility while intubated and sedated for management of severe ARDS. She had undergone extensive infectious workup and the etiology was attributed to COVID-19 pneumonia and or bleomycin toxicity. She was started on Methylprednisolone for management of bleomycin toxicity and suspected organizing pneumonia. During her hospitalization, she developed septic shock for which she received broad spectrum antibiotics and pressor support. On day 12 of her hospitalization, vasopressin was discontinued and within 12 hours, there was a rise in serum sodium from 134 to 146 along with polyuria with dilute urine (daily urine output of ∼6-7 liters, urine osmolality decreased from 771 to 279 and urine specific gravity decreased from 1. 037 to 1. 026). No diuretics were administered and serum glucose was without excursions. With administration of 2 mcg DDAVP, urine osmolality increased by more than 50% from 279 to 497, serum sodium decreased from 146 to 141 and urine specific gravity increased from 1. 004 to 1. 026 confirming the diagnosis of central DI. CT head was negative. MRI brain could not be done due to hemodynamic instability. Endocrinology was consulted and concomitant adrenal insufficiency testing was not sought due to chronic steroid therapy. The dose of DDAVP was titrated to ∼1-2 mcg per day based on serum sodium levels and daily urine output. Approximately 10 days later, Vasopressin was restarted due to hemodynamic instability and with ongoing DDAVP therapy, hyponatremia was noted. Thus, DDAVP was discontinued while on vasopressin. She was continued on vasopressin for the remainder of her hospitalization ∼ 11 more days until she unfortunately passed away. Discussion Our patient developed central diabetes insipidus after withdrawal of vasopressin. She continued to require DDAVP for ∼10 days before Vasopressin had to be restarted due to hemodynamic instability, after which DDAVP had to be discontinued due to concern of SIADH. Central diabetes has been linked to critical illness in a transient state driven by depletion of endogenous stores, negative feedback repression and posterior pituitary hypoperfusion. However, our patient continued to require exogenous supplementation. More research is needed in this regard to elucidate the differing etiologies and characteristics of transient versus permanent DI. Critical illness is a rare but extremely important cause of central DI and can quickly prove to be life threatening without timely diagnosis and treatment. Presentation: Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.

Biorefinery-oriented full utilization of food waste and sewage sludge by integrating anaerobic digestion and combustion: Synergistic enhancement and energy evaluation

Biorefinery-oriented full utilization of organic wastes by integrating anaerobic digestion and combustion is a promising approach. The objectives of this study were to investigate the effect of the co-treatment of food waste and sewage sludge on the performance of the combined system in terms of methane production, combustion characteristics and total energy output. The anaerobic co-digestion of food waste with sewage sludge showed a clear synergistic enhancement at the optimal food waste/sewage sludge ratio of 2:2, where the methane yield increased by 99 mL/g VSadded compared with the theoretical value. The analysis of aqueous products suggested that the synergistic effect was attributed to reduced volatile fatty acids accumulation and ammonia inhibition. Furthermore, the digestate at a ratio of 2:2 showed the best combustion characteristics with the highest comprehensive combustion index and combustion stability index of 4.87 × 10−7%2 min−2 °C−3 and 4.80 × 103%2 min−2 °C−3, respectively, which could be resulted from the more stable organic components and the catalytic effects of inorganic minerals. Finally, the energy evaluation showed that the co-treatment would increase the daily energy output and specific energy output of 100 t/d full-scale plant by 14.3 GJ/day-33.7 GJ/day and 0.3 GJ/t-0.6 GJ/t, respectively. These findings could provide some valuable information for anaerobic digestion-combustion-based biorefinery of organic wastes.

Feasibility of condensate water recycle of split air handling unit in Chinese University buildings

Recycling the condensate water of the air conditioner could be explored as an alternative water source to contribute to building the green campus. This paper explored the condensate water production through actual measurement based on a split air handling unit (SAHU) in a university building. Then, the statistical analysis was used to analyze the recycling feasibility and the impact factors of the condensate water production in 31 Chinese provincial capital cities to obtain the recycling potential map of the condensate water generated from a SAHU. Results showed that: (1) In the measurement, the amount of condensate water produced by a single split air conditioner was 1.6 kg from 12:40 to 13:40. Therefore, the daily output of condensate water of the air conditioner with the university operation schedule could reach 52.99 kg during the main air-conditioning season. (2) Among the 31 provincial capital cities in China, the largest condensate water outputs could be found in the Hot Summer and Warm Winter zone and the Hot Summer and Cold Winter zone, with an average monthly output of 1600 kg and 1100 kg, respectively. (3) Regression analysis showed that the dry-bulb temperature and dew point temperature of outdoor air had the highest positive and significant influence on condensate water production. The objective of this study is to provide theoretical guidance for the design and energy conservation evaluation of the feasibility of SAHU condensate water recycling in universities.

ВЛИЯНИЕ ТОРАСЕМИДА И ИНДАПАМИДА НА ЭКСКРЕЦИЮ МАГНИЯ, КАЛИЯ, КАЛЬЦИЯ И НАТРИЯ У ЖЕНЩИН ПОСТМЕНОПАУЗАЛЬНОГО ВОЗРАСТА С АРТЕРИАЛЬНОЙ ГИПЕРТЕНЗИЕЙ И ХРОНИЧЕСКОЙ СЕРДЕЧНОЙ НЕДОСТАТОЧНОСТЬЮ В ЗАВИСИМОСТИ ОТ НАЛИЧИЯ ДЕФИЦИТА МАГНИЯ

The aim of study was to assess torasemide and indapamide effects on magnesium (Mg), potassium (K), calcium (Ca), and sodium (Na) excretion in postmenopausal women with hypertension and heart failure with preserved ejection fraction (HFpEF) depending on Mg exchange. Material and methods. 140 postmenopausal women with hypertension and HFpEF were examined. Based on Mg-tolerance test results, patients were divided into 2 groups: with (n = 72) and without Mg deficiency (n = 68) with randomization into 4 subgroups: 1a, 1b – 36 patients and 2a, 2b - 34 women in each. Subgroups 1a and 2a received torasemide 5 mg, 1b and 2b – indapamide 2.5 mg. Daily diuresis, Na, K, Ca and Mg excretion were determined before and after diuretics use. Results. Diuretics caused equal (p>0.05) increase (p<0.001) in daily urine output and natriuresis by 561 (95%CI: 556–571) ml and 71.0 (95%CI: 68.9– 73.1) mmol/24h. K excretion increased (p<0.0001) only with indapamide use by 21.1 (95% CI: 18.4-23.8) mmol / 24h and 22.3 (95% CI: 19.5-25.0) mmol / 24h in groups 1b and 2b. Mg excretion increase was not detected (p>0.05) only in patients with Mg deficiency torasemide subgroup, but Ca loss remained unchanged (p>0.05) in indapamide subgroups. K/Na and Ca/Na ratio decreased in all groups, while Mg/Na increased with indapamide use and decreased with torasemide use. Torasemide decreased (p<0.001) Mg/Ca excretion ratio, but indapamide decreased (p<0,0001) the one. Conclusion. Indapamide caused significant increase in K, Mg excretion and Mg/Ca, while torasemide increased Ca loss, decreased Mg/Ca, and did not affect K loss in postmenopausal women with hypertension, HFpEF regardless to Mg deficiency. Torasemide did not lead to Mg losses increase in macronutrient-deficiency patients.

Inverted Solar Stills: A Comprehensive Review of Designs, Mathematical Models, Performance, and Modern Combinations

Fresh water is scarce, making it a worldwide issue. In order to address global freshwater demand, a filtration technique is needed. Solar distillation (SD) that purifies brackish and subterranean water has been proven to be a promising green technology. It produces distilled water which can be used as potable water for drinking and other purposes. The designs, operations, and configurations of several inverted solar stills are thoroughly examined in this article. All techniques for solar water distillation to separate saltwater from freshwater have the same fundamental idea. It has been demonstrated that for a specified mass of water in the top basin, the daily output of an inverted absorber double-basin solar still (IASS) grows with increasing water depth in the bottom basin. Nevertheless, as the water depth in the bottom basin rises from 1 cm to 5 cm, the output of an inverted absorber double-basin solar system falls by about 27%. At water depths of 4, 6, and 8 cm, the daily yields from inverted absorber solar stills paired with a refrigeration cycle (RIASS) were 6.4, 10.08, and 9.5 L/day, respectively. The results also showed a substantial rise in water temperature in the inverted absorber solar still as a result of lower bottom heat loss and larger absorptivity. In this study, the emphasis on energy, efficiency, and environmental concerns remains with the modified multi-wick basin-type inverted absorber solar panel. The performance of the inverted trickling solar still was assessed with a 60 ppm average salinity under various sun radiation, feed water flow rate, and existence conditions for natural convection. It was found that the still could produce 2.55 L/day m2 of fresh water, a 15% increase. Brackish water with a salinity of 6000 ppm was used to test the still in November at tilt angles of 47° and 32°. Condensate production at the specified angles was 2.8 and 2 L/d, respectively. A total output of 6.907, 5.681, and 4.650 kg/m2/day was also generated using the modified multi-wick basin-type inverted absorber solar still (MMWBIASS) at water depths of 1, 2, and 3 cm, respectively. With black cotton wicks, the MMWBIASS had a total thermal efficiency of 34.04%, 28.17%, and 23.61%.

Multi-objective coordinated optimization of power system with wind power accommodation

To decrease wind curtailment rate and increase wind power accommodation, power purchase area should increase wind power purchase. However, the current electricity price of wind power is higher than that of thermal power, which makes wind power accommodation difficult to quantify. It is not practical to optimize these two objectives of the wind power accommodation and power purchase cost. Based on this contradiction, this paper describes this contradiction by constructing a multi-objective optimization model (MOOM) that considers the above two objectives. Firstly, the model is resolved by hybrid particle swarm optimization and gravity search algorithm (HPSO-GSA) to obtain Pareto optimal solution set. Then, according to fuzzy satisfaction function, Pareto optimal solution is selected from Pareto optimal frontier. Finally, the typical daily load and wind farm output value in spring of a certain region are taken as examples for simulation verification. It is verified that the proposed method can indeed provide a scientific power purchase scheme for regional power purchase.

Parametric study of a novel air-based photovoltaic-thermal collector with a transverse triangular-shaped block

This study discusses the effects of various parameters on the energy output and efficiency of a novel air-based photovoltaic-thermal collector with a transverse triangular-shaped block using numerical analysis. The transverse triangular-shaped block, designed by the authors, enhances heat transfer in the collector by accelerating the air velocity and mixing hot and relatively cold air in an air duct. Using energy balance equations, a mathematical model for the collector with a transverse triangular-shaped block was developed and validated with experimental data obtained from a previous study. The selected parameters were height, air mass flow rate, length, solar intensity, and wind velocity. The highest energy output was achieved at a height of 0.03 m for a solar intensity of 1000 W/m2 and an air mass flow rate of 0.13 kg/s. This study also compared the daily energy output of a previously experimented photovoltaic-thermal collector with that of a collector at a height of 0.03 m. The results showed that daily thermal, electrical, and thermally equivalent net energy outputs were increased by 36.97%, 2.59%, and 8.64%, respectively, and confirmed that the proper selection of design and operating parameters can provide improved performance of the collector.

Investigation and performance analysis of active solar still in colder Indian Himalayan region

Traditional basin-type solar stills are not as popular due to their lower productivity, but a number of ways have been developed globally to increase their production capacity. This article demonstrates an overview of the recent studies aimed at improving the productivities and the effective functioning of conventional solar stills. In order to have a better insight of the thermal performance, the studies focused on evaluating the thermodynamic efficiencies of solar stills have also been reviewed and found that active solar distillation has strong potential in enhancing the performance characteristics of basin type systems. It was observed that, enormous efforts made by various researchers in understanding and improving the thermal characteristics of solar stills for better output have been majorly examined in hotter and arid regions, and solar stills for colder regions need an attention too. In this context, the proposed work attempts to carry out an experimental study to assess the effect of lower ambient conditions on performance characteristics of an active solar in an Indian cold hilly location. The observations from the study showed that the effective daily output of the active solar still was as high as twice the daily distillate output produced by the conventional passive still. The thermodynamic efficiencies of the active system were also evaluated. Further, during different sunny days, the variation in average exergy and energy efficiencies of the active system ranged from 14.86 to 16.18% and 1.95–2.41%, respectively. Due to the prevailing storing effect, the nocturnal productivity of solar still was increased at deeper water levels. The study also helped to conclude that the exergy destruction in solar still is highly influenced by low ambient temperatures and in future, effective design optimization studies can be carried out to gain the benefits through minimized energy/exergy losses.

Cortisol, cognition and Alzheimer’s disease biomarkers among memory clinic patients

ObjectiveThis study aims to investigate the relationship between diurnal cortisol patterns, cognition and Alzheimer’s disease (AD) biomarkers in memory clinic patients.MethodMemory clinic patients were recruited from Karolinska University Hospital in...

An Assessment of Biomedical Waste (BMW) Production and Management and its Impact on the Environment and Disease Transmission Amidst the COVID-19 Pandemic in the Philippines

The study aimed to analyze the impact of pandemic-related BMW production and management in the Philippines and its potential role in transmitting the COVID-19 virus via a mixed-methods analysis of data from surveys of different sectors (consumers of medical waste, deliverymen, and medical workers) and using secondary sources. The results revealed that the most common types of PPE used in the country are disposable face masks and face shields, wherein all respondents reported an increase in the consumption of medical materials. An improper disposal of an estimated 85 million disposable face masks and 50 million face shields in the Philippines poses a serious threat to the environment and health in the Philippines, a biodiversity hot spot. There was a strong correlation between the increased exposure to BMW and laxer degrees of implementation of proper BMW disposal practices. The paper also established an estimated consumption of ≈ 120.5 million face masks, ≈ 71.4 million face shields, ≈ 38 million disposable gloves, and ≈ 4.1 million full-body suits per day in the Philippines. The actual output of biomedical waste in the country drastically increased in a year, comprising an average daily output of 3,390 tons of BMW (≈ 482 tons for face masks, ≈ 2,544 tons for face shields, ≈ 198 tons for disposable gloves, and ≈ 167 tons for full-body suits which is an important discovery regarding the biomedical waste in the country. These estimates were found to be higher than those reported by the Asian Development Bank in 2020. All sectors reported low awareness levels and confidence in the country's effectiveness in implementing current BMW management practices.

Effects of Magnetic Field on the Performance of Solar Distillers: A Review Study

Due to the rising demand for treated water, the enhancement of potable water yield technologies, such as traditional solar distillers, is a pressing concern. Solar desalination is one of the easiest techniques for producing fresh water from salt water. It has several benefits, not the least. It utilizes free solar energy. Moreover, it is a simple and inexpensive technique compared to other alternatives. They are, nevertheless, relatively inefficient devices. Many studies have been done to boost the daily output of solar stills by using many active strategies to produce a large amount of evaporation and condensation compared to a basic standard type distiller. The magnetic field (MF) is one of the most important and recent techniques affecting the productivity of the solar still due to its positive impact on the water evaporation rate. The primary focus of the current study is to review the effects of magnetic field approaches on the distillate production, performance, and thermal efficiency of several types of solar distillers. Based on previous studies, the magnetic field is responsible for increasing the partial pressure difference between water and glass cover. The change occurs in the hydration shells of the saltwater, which should enhance the evaporation rate and improve the performance of solar still. Besides, the magnetic field significantly reduces the surface tension of salty water, which leads to increased evaporation. Furthermore, the intensity, direction, position, and magnet sizes of magnetic have a strong effect on the rate of water evaporation as well as the rate of heat transfer.

Hybrid cooling techniques to improve the performance of solar photovoltaic modules

Photovoltaic (PV) module efficiency is often impeded by concomitant temperature elevations, which may lead to cell degeneration and decreased electrical efficiency. Cooling techniques are commonly used to avoid this problem; however, current techniques, such as water-sprayer and active cooling systems, still have limitations, including the scattering and reflection of photons. In this study, we present a new active dual-cooling system design using two thermoelectric cooling (TEC) units fixed to the back of a PV module to provide rear-end cooling, which were experimentally and numerically studied. A water-thin film cooling system (WFCS) was maintained at the top surface of the module using a small affixed 72-W DC pump, for improving efficiency. For testing, the system was installed on the roof of an agricultural building in South Korea, and its performance efficiency was compared with that of a reference cooling-free PV module. The results showed that the innovation led to a decrease in the module temperature to 21 °C, which led to an efficiency improvement of 11.23 % with an increase in the daily output energy of 8.3 %. Additionally, a numerical simulation model based on the Finite Element Method (FEM) was used to evaluate the temperature profile of the PV module owing to the cooling technique and temperature distribution on the module’s top surface. The maximum temperature reductions were 17.27 and 12 °C in the experimental and simulation results, respectively.

Octreotide Dosing in the Medical Management of Chyle Leak Following Otolaryngologic, Thoracic, and Trauma Surgery: A 9-Year Evaluation

Background: Chyle leak is a rare complication following otolaryngologic, thoracic, and trauma surgery wherein the thoracic duct is transected. Case reports and small case series describe octreotide for the medical management of chyle leak, but limited data exist to determine the ideal dose. Objective: To evaluate octreotide dosing in patients with acute chyle leak. Methods: This retrospective, single center, cohort study evaluated adult patients admitted to the otolaryngology, cardiothoracic, and trauma surgery teams over a 9-year period. Patients diagnosed with a chyle leak who received octreotide were eligible for inclusion. Groups were defined as successful medical management or failure requiring definitive surgery. The primary endpoint was daily octreotide dose between groups. Results: Forty-seven patients were included with 29 (61.7%) admitted to the otolaryngology service and 44 (93.6%) with surgical complication as the chyle leak cause. Thirty-two (68.1%) patients had successful medical management while 15 (31.9%) patients failed and required surgical intervention. There was no difference in median daily octreotide dose (250 [IQR, 170-288] µg vs 253 [IQR, 200-282] µg, P = .9). Octreotide weight-based dose, treatment duration, and route of administration were similar between groups. Daily drain output and complete bowel rest were significantly higher in the failure group. Daily drain output was identified as an independent risk factor for failure. Conclusion: Octreotide dose was similar in patients with and without successful medical management of chyle leak. Future studies are needed to determine optimal octreotide dosing and elucidate the relationship between octreotide, drain output, and surgical intervention need.