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Regular water quality monitoring is becoming desirable due to the increase in water pollution caused by both climate change and the generation of industrial chemicals. Unmanned vehicles have emerged as key technologies for remote data acquisition, providing fast and accurate methods for water quality monitoring. However, current research on unmanned vehicles has not systematically examined their features and limitations, which are crucial for identifying future research directions and applications of unmanned vehicle technologies. Therefore, this study extensively reviews the advancements in remote data acquisition and processing using unmanned vehicle technologies for water quality monitoring to provide valuable insights for future research. First, the types of unmanned vehicles and their application ranges for water quality monitoring are summarized. Among the unmanned vehicle technologies, unmanned aerial vehicles are considered primary platforms for water quality monitoring due to their wide data acquisition range and their ability to accommodate diverse sensors and samplers. Also, the types of samplers and sensors mounted on the unmanned vehicles are analyzed based on their characteristics. It is concluded that spectral sensors offer the most cost-effective approach for acquiring real-time water quality data. Furthermore, algorithms that convert image data into water quality data are examined, focusing on data preprocessing, analysis, and validation. The findings reveal a close relationship between the analysis of spectral characteristics of each water quality parameter and the wavelength ranges of red and red-edge. Lastly, future research directions for unmanned vehicle technologies are further suggested based on the summarized technological limitations. [Display omitted] • Unmanned vehicle-based remote water quality monitoring technologies were reviewed. • Types of the unmanned vehicles and their application ranges were investigated. • Unmanned vehicle mountable water samplers and sensors were categorized. • Processing algorithms were analyzed to convert the image data to water quality data. • Future research directions were suggested by analyzing current development status. [ABSTRACT FROM AUTHOR]

While single-stage is the general configuration for seawater reverse osmosis (SWRO), the two-stage design can increase the overall recovery of an SWRO system. Due to its high-recovery operation, the specific energy consumption (SEC) of two-stage SWRO is higher than that of single-stage. Thus, the two-stage configuration has not been extensively applied in the current desalination market. In contrast, recent studies have reported that the two-stage design can lower the SEC of SWRO compared to that of single-stage. However, the analyses were biased towards SEC, and the practical design aspects (e.g., permeate quality, water flux, and design ratios) were not systemically considered. Thus, this study examines the applicability of a two-stage SWRO system with a capacity of 100,000 m3/d that employs 1200 pressure vessels (PVs). Two-stage SWRO actually consumed a greater amount of energy than that of single-stage for typical SWRO recovery with the same number of PVs. In contrast, single- and two-stage SWRO produced permeate similar in quality, while the two-stage exhibited superior water-flux distribution along the PVs. Additionally, optimal ratios of permeate flow rate and number of PVs were determined by energy recovery devices type, where the ratio of 1:2 was selected for the reverse osmosis system with a pressure exchanger and 2:1 for that with a Pelton turbine. Considering SEC and other operational aspects, the use of two-stage SWRO was feasible at a 50–70% recovery rate. Image 1 • Two-stage SWRO is fundamentally analyzed and optimized for seawater desalination. • SEC of two-stage SWRO is higher than that of single-stage in typical recovery. • Water quality of single- and two-stage SWRO is similar at the same average flux. • Optimal ratios of permeate flow rate and number of PVs vary depending on ERD types. • Two-stage SWRO is more energy-efficient at a high recovery rate (e.g., 50–70%). [ABSTRACT FROM AUTHOR]

Seawater is receiving consideration as an infinite water source in the current era of water shortage. The application of seawater reverse osmosis (SWRO) to prepare seawater for human use is increasing exponentially owing to its high energy efficiency among desalination technologies. However, SWRO is still energy-intensive, and thus needs to be improved further to become more environmentally sound (i.e., producing less CO 2). To tackle such a challenge, this study was conducted to propose strategies to lower the specific energy consumption (SEC) of the SWRO process. From the results of extensive review and theoretical analysis, three directions were proposed for improving the energy efficiency of the SWRO process: i) minimize the irreversible work of the high-pressure pump, ii) decrease the osmotic pressure of the feed, and iii) recover osmotic energy from reverse osmosis (RO) concentrate. After the feasibility of each approach was identified by assessing the theoretical minimum energy and the maximum available margin, strategies for each direction were presented with a technical description, then critically evaluated by considering their practical application. Because this paper includes theoretical perspectives for energy savings in SWRO, it provides comprehensive ideas for lowering the SEC of SWRO desalination plants in the future. Image 1 • Three improvement axes for low-energy reverse osmosis were analyzed theoretically. • Maximum margin and obtainable energy reduction in each axis were calculated. • Minimizing irreversibility is effective, but operating issues are challenging. • Decreasing osmotic pressure can be effective only with additional low-saline water. • Recovering osmotic energy may be effective, but needs to be further developed. [ABSTRACT FROM AUTHOR]

• Critical review of energy consumption of seawater reverse osmosis plants. • Collection of more than 70 datasets for large-size seawater reverse osmosis plants. • Investigation of trends in the application of seawater reverse osmosis plants. • Analysis of factors associated with energy consumption of seawater reverse osmosis. • Future directions to reduce energy consumption of seawater reverse osmosis plants. High specific energy consumption (SEC) is the main barrier for the expansion of seawater reverse osmosis (SWRO). Therefore, the main objective of current SWRO research is to lower the SEC of SWRO plants. However, SEC of SWRO plants has not been systemically explored or analyzed, despite the need for information to develop appropriate strategies to reduce SEC. Therefore, this study aims to review and analyze SWRO plants for a comprehensive understanding of their SEC. First, trends in SWRO application are investigated using more than 70 datasets on large-scale SWRO. The analysis explains the increasing number of large-size SWRO plants, the SEC reduction by isobaric energy recovery devices (ERDs), and the use of different SWRO configurations to meet the energy and quality requirements. Factors associated with SEC (i.e. , feed conditions, target conditions, and equipment efficiency) are also analyzed. High salinity increases energy demand, whereas the temperature effect on energy consumption is not entirely clear. High-efficiency ERDs and pumps can reduce SEC, but overall SEC cannot be explained by these factors alone. SEC is also affected by target water quality and quantity. Moreover, specific SWRO designs can improve the system to efficiently achieve the established goals. Furthermore, future directions to develop low-energy SWRO plants are discussed. [ABSTRACT FROM AUTHOR]

Ultrapure water (UPW) is essential in the semiconductor industry for rinsing and cleaning products. With the growing demand for UPW, various feed water sources such as tap water, surface water, and wastewater are utilized to produce UPW. However, these feed water sources contain various low molecular weight organic matters (LMWOMs), which can adversely affect the quality of semiconductors when present in treated UPW. Therefore, achieving the complete removal of LMWOMs is crucial in the UPW production process. However, the current reverse osmosis (RO) and vacuum ultraviolet (VUV) processes employed for UPW production have limitations in achieving complete LMWOM removal. Therefore, this study is conducted to investigate the mechanisms of LMWOM removal in RO and the performance of VUV for high-quality UPW production. Six LMWOMs found in the semiconductor industry were tested for lab- and pilot-scale experiments. The result showed that size exclusion is the main mechanism of LMWOM removal in the RO process. However, methanol, ethanol, and urea were not efficiently removed by RO membranes. In addition, a lab-scale VUV experiment was performed under accelerated conditions to examine the oxidation mechanism of LMWOM. The LMWOM with low reactivity to hydroxyl radicals, such as tetramethylammonium hydroxide (TMAH) and urea, were not removed perfectly within 60 min and 180 min, respectively. Furthermore, a pilot-scale VUV experiment was performed to examine the oxidation of LMWOM under real UPW production conditions. Despite observing a correlation in the pseudo-first-order rate constants between the lab-scale and pilot-scale experiments, the removal of TMAH and urea was still not achieved even with a lamp power of 320 W. As urea was not completely removed by either RO or VUV, strategies for UPW production using current water sources are discussed to develop future UPW technologies. [Display omitted] • The fate of six LMWOMs was analyzed in RO and VUV processes for UPW production. • Size exclusion is the most dominant mechanism for the removal of LMWOMs in RO. • High reactivity with hydroxyl radicals is key to the removal of LMWOMs through VUV. • Pilot-scale VUV results correlate with lab-scale VUV experiments in real UPW conditions. • Urea is the most problematic LMWOM in the UPW process for the semiconductor industry. [ABSTRACT FROM AUTHOR]

The overall goal is to study the effect of low-level laser therapy (LLLT) on membrane distribution of major water channel protein aquaporin 5 (AQP5) in salivary gland during hyperglycemia. Par C10 cells treated with high glucose (50 mM) showed a reduced membrane distribution of AQP5. The functional expression of AQP5 was downregulated due to intracellular Ca 2+ overload and ER stress. This reduction in AQP5 expression impairs water permeability and therefore results in hypo-salivation. A reduced salivary flow was also observed in streptozotocin (STZ)-induced diabetic mice model and the expression of AQP5 and phospho-AQP5 was downregulated. Low-level laser treatment with 850 nm (30 mW, 10 min = 18 J/cm 2 ) reduced ER stress and recovered AQP5 membrane distribution via serine phosphorylation in the cells. In the STZ-induced diabetic mouse, LLLT with 850 nm (60 J/cm 2 ) increased salivary flow and upregulated of AQP5 and p-AQP5. ER stress was also reduced via downregulation of caspase 12 and CHOP. In silico analysis confirmed that the serine 156 is one of the most favorable phosphorylation sites of AQP5 and may contribute to the stability of the protein. Therefore, this study suggests high glucose inhibits phosphorylation-dependent AQP5 membrane distribution. High glucose induces intracellular Ca 2+ overload and ER stress that disrupt AQP5 functional expression. Low-level laser therapy with 850 nm improves salivary function by increasing AQP5 membrane distribution in hyperglycemia-induced hyposalivation. [ABSTRACT FROM AUTHOR]

Abstract: IL-6 is a multifunctional cytokine that is important for immune responses, cell survival, apoptosis, and proliferation. However, little is known about the correlation between the IL-6 signaling pathway and DNA damage in human tumors. The present study demonstrates the role of the IL-6/STAT3 signaling pathway in human tumor cells exposed to DNA damage. Tumor cells exposed to DNA damage increase the expression and secretion of IL-6 and the phosphorylation of JAK1 and STAT3. The activation of the JAK1–STAT3 signaling pathway is inhibited by knockdown of gp130 or neutralization of soluble IL-6, implying that DNA damage induces the phosphorylation of JAK1 and STAT3 by autocrine IL-6. Interestingly, inhibition of the IL-6/STAT3 signaling pathway impairs the growth of tumor cells exposed to DNA damage and results in the induction of senescence. Therefore, the present study suggests that IL-6 inhibits senescence but promotes the survival and proliferation of tumor cells exposed to DNA damage through the activation of the JAK1–STAT3 signaling pathway. [Copyright &y& Elsevier]