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In micro-irrigation systems, distinct media filters and filtering materials are employed to remove suspended solids from irrigation water and thereby avoid emitter obstruction. Turbidity is related to suspended solids and dissolved oxygen depends on organic matter load. At this time, no models exist that are trustworthy enough to forecast the dissolved oxygen and turbidity at the outlet when utilising various media configurations and filter types. The objective of this investigation was to construct a model that can identify turbidity and dissolved oxygen at the filter outlet in advance. This study presents an algorithm for meta-heuristic optimisation inspired by populations termed Differential Evolution (DE) in conjunction with Support Vector Regression (SVR) (DE /SVR-relied model). This is an effective machine learning method, with seven kernel types for calculating the output turbidity (Turb o) and the output dissolved oxygen (DO o) from a dataset comprising 1,016 samples of various reclaimed water-using filter types. The type of media and filter, the height of the filter bed, the cycle duration, and the filtration velocity, as well as the electrical conductivity at the filter inlet, pH, inlet dissolved oxygen, water temperature, and the input turbidity are all tracked and analysed in order to achieve this. The best-fitted DE/SVR-relied model was constructed to predict the Turb o and DO o as well as the input variables' relative importance. Determination coefficients for the best-fitted DE/SVR-relied model for the testing dataset were 0.89 and 0.92 for outlet turbidity (Turb o) and outlet dissolved oxygen (DO o), respectively, showing a good predictive performance which are of great importance for the management of drip irrigation systems. [Display omitted] • Predictive DE/SVR models of the Turb o and DO o in granular filters are built. • The relative importance of the input variables in this process are determined. • The DE/SVR results for the Turb o and DO o are compared with the experimental values. • The correlation coefficients of the best SVR model are 0.95 and 0.96, respectively. [ABSTRACT FROM AUTHOR]

Animals often moderate behaviours based on environmental and social cues to enhance their chances of survival and reproductive success. This requires reliable cues that reflect changes in ambient conditions. Environmental pollutants can increase communication costs and distort the accuracy of received information, leading to negative effects on the outcome of behavioural adjustments. Consequently, selection may reduce behavioural plasticity to avoid errors or promote more prudent decision making when certain cues become unreliable. In aquatic ecosystems, water turbidity shows high levels of natural variation, but human activities amplify its magnitude and extent by increasing algae and suspended solids in the water. Here, we investigated how elevated levels of water turbidity affected mating decisions made by female guppies in a laboratory setting. Guppies are a widespread species with a broad tolerance of polluted environments, and females rely heavily on visual cues when making mate choice decisions. We manipulated turbidity by adding suspended solids to water and tested how this affected female preference for males with more orange coloration. We found that females spent more time near males with a greater area of orange coloration in low turbidity water, but that this preference disappeared in both the mid and high turbidity water treatments. Moreover, female preferences were repeatable in low turbidity water and high turbidity water but not in mid turbidity water. Together, our results suggest that water turbidity impairs the ability of females to discern male coloration and affects the consistency of mate preferences. This could have consequences for the evolution of male coloration in turbid waters. • Male guppies have vibrant colour patterns indicating quality. • We investigated how water turbidity affects mating decisions by female guppies. • Females preferred to associate with more colourful males in low turbidity water. • Increased turbidity resulted in no preference for more colourful males. • Female mate preference was not repeatable in mid turbidity water. [ABSTRACT FROM AUTHOR]

Water turbidity alters prey detectability and prey selection by a predator. In dimorphic mesopredators, the effect of water turbidity on foraging success may be sex specific, primarily due to sex differences in reproductive allotment, body size and vulnerability to predation. To experimentally test the effect of turbidity on prey consumption with respect to sex, we used turquoise killifish (Nothobranchius furzeri), a small fish from ephemeral savanna pools in southeast Africa that vary widely in turbidity. Large males possess conspicuous nuptial coloration while females are smaller and drab. Vision is assumed to be a fundamental sense for turquoise killifish, despite often living in very turbid water. As mesopredators, killifish regulate the invertebrate community in ephemeral pools. We tested the consumption of bloodworms (benthic and red‐coloured) and glassworms (pelagic and transparent) under clear (<1NTU) and turbid (320 NTU) water conditions. We found that turquoise killifish maintained their overall foraging success irrespective of turbidity. In both the clear and turbid water, the females consumed three times more food than males relative to their body mass. This likely stems from the females' high nutritional demands due to daily reproduction. It also suggests that females are not risk‐aversive in clear water despite their smaller size. Water turbidity affected the type of prey consumed by turquoise killifish and demonstrated its potential to affect the community structure of invertebrate species in ephemeral pools. [ABSTRACT FROM AUTHOR]

The effects of turbidity and sedimentation stress on early life stages of corals are poorly understood, particularly in Atlantic species. Dredging operations, beach nourishment, and other coastal construction activities can increase sedimentation and turbidity in nearby coral reef habitats and have the potential to negatively affect coral larval development and metamorphosis, reducing sexual reproduction success. In this study, we investigated the performance of larvae of the threatened Caribbean coral species Orbicella faveolata exposed to suspended sediments collected from a reef site in southeast Florida recently impacted by dredging (Port of Miami), and compared it to the performance of larvae exposed to sediments collected from the offshore, natal reef of the parent colonies. In a laboratory experiment, we tested whether low and high doses of each of these sediment types affected the survival, settlement, and respiration of coral larvae compared to a no-sediment control treatment. In addition, we analyzed the sediments used in the experiments with 16S rRNA gene amplicon sequencing to assess differences in the microbial communities present in the Port versus Reef sediments, and their potential impact on coral performance. Overall, only O. faveolata larvae exposed to the high-dose Port sediment treatment had significantly lower survival rates compared to the control treatment, suggesting an initial tolerance to elevated suspended sediments. However, significantly lower settlement rates were observed in both Port treatments (low- and high-dose) compared to the control treatment one week after exposure, suggesting strong latent effects. Sediments collected near the Port also contained different microbial communities than Reef sediments, and higher relative abundances of the bacteria Desulfobacterales, which has been associated with coral disease. We hypothesize that differences in microbial communities between the two sediments may be a contributing factor in explaining the observed differences in larval performance. Together, these results suggest that the settlement success and survival of O. faveolata larvae are more readily compromised by encountering port inlet sediments compared to reef sediments, with potentially important consequences for the recruitment success of this species in affected areas. [ABSTRACT FROM AUTHOR]

Downward long-wave irradiance (DnLWI) is a variable that directly influences the surface net radiation, which in turn affects weather and climate. Due to the lack of abundant DnLWI observations, numerical weather prediction (NWP) models provide a very effective way to yield the DnLWI. Nevertheless, the reliability of the DnLWI predicted by the NWP models needs the evaluation based on the observations or accurate radiative transfer models. In this study, the DnLWI product of the China Meteorological Administration mesoscale model (CMA-MESO) was extensively validated using long-term high time-resolution (1 min) DnLWI measurements carried out at 42 sites in China. The results showed that the DnLWIs predicted by the CMA-MESO model generally agreed well with the observations, i.e., with a relative mean bias error (rMBE) of –2.0 %, but overestimated them under overcast (3.1 %) and underestimated them under dry (–5.3 %) and cloudless (–5.2 %) conditions. It is also found that the discrepancies in the DnLWI predicted by the CMA-MESO model exhibited spatial and diurnal variations, e.g., the discrepancies were significantly smaller at night than those during the day due to the stable nocturnal boundary layer. According to the results of the partial least squares analysis, the high cloud cover, medium cloud cover, planetary boundary layer height, and integrated cloud ice were the most important factors affecting the accuracy of the DnLWIs predicted by the CMA-MESO model under all sky conditions. By comparing the outputs of the CMA-MESO model and the MODerate resolution atmospheric TRANsmission (MODTRAN) model, it was found that the uncertainties in the DnLWI predicted by the CMA-MESO model mainly arose from an inappropriate consideration of the high and medium clouds under all sky conditions as well as shortcomings in the radiation scheme under cold dry cloudless conditions. [ABSTRACT FROM AUTHOR]

Turbidity stands as a crucial indicator for assessing water quality, and while turbidity sensors exist, their high cost prohibits their extensive use. In this paper, we introduce an innovative turbidity sensor, and it is the first low-cost turbidity sensor that is designed specifically for long-term stormwater in-field monitoring. Its low cost (USD 23.50) enables the implementation of high spatial resolution monitoring schemes. The sensor design is available under open hardware and open-source licences, and the 3D-printed sensor housing is free to modify based on different monitoring purposes and ambient conditions. The sensor was tested both in the laboratory and in the field. By testing the sensor in the lab with standard turbidity solutions, the proposed low-cost turbidity sensor demonstrated a strong linear correlation between a low-cost sensor and a commercial hand-held turbidimeter. In the field, the low-cost sensor measurements were statistically significantly correlated to a standard high-cost commercial turbidity sensor. Biofouling and drifting issues were also analysed after the sensors were deployed in the field for more than 6 months, showing that both biofouling and drift occur during monitoring. Nonetheless, in terms of maintenance requirements, the low-cost sensor exhibited similar needs compared to the GreenSpan sensor. [ABSTRACT FROM AUTHOR]

The hydrosilylation reaction is a suitable route to prepare efficient, transparent, and low‐viscose silicone surfactants with low surface tension. Initial materials, the catalyst used, and experimental conditions are highly effective variables to achieve the maximum efficiency of the reaction, reduce the consumption of the catalyst, and prevent side reactions. To draw a comprehensive conclusion on the effect of these variables, a series of trimethylsiloxy‐terminated poly (methylhydro‐dimethyl)siloxanes copolymer (abbreviated as RSiH with different preceding numbers) and two unsaturated polyethylene glycols (UPEG200 and UPEG400) were selected, and the reactions in the presence of two platinum‐based catalysts, namely, hexachloroplatinic acid and ammonium hexachloroplatinate, were statistically studied by Design of Experiment. After initial pre‐investigations, the amounts of reactant and catalyst were subjected to analysis of variance using response surface methodology (RSM). Based on the results, low‐viscose and low‐surface tension silicone surfactants were obtained using UPEG400, RSiH105, and (NH4)2PtCl6 as catalysts, at temperatures over 170 °C. The best results were obtained with a relatively low concentration of the catalyst between 2.57 × 10−6 and 2.72 × 10−6 equivalent catalyst per UPEG. The relative equivalent ratio of [UPEG]/[RSiH] at the optimum condition was 1.6, which provided a surface tension below 21 mN/m together with a minimum amount of unreacted RSiH (less than 3%). The silicone surfactant was characterized as a pure product by a series of spectroscopic methods, such as FT‐IR and 1H NMR spectroscopies, as well as bromine number index. These excellent properties make this compound a new alternative in various industries. [ABSTRACT FROM AUTHOR]

The presence of impurities, microorganisms, enzymes, suspended solids, and impurities in unclarified pomelo juice negatively affected the quality and shelf-life of the product in the food industry. The objective of this study focuses on the clarification of fresh pomelo juice using an ultrafiltration (UF) process. The study examined the influence of the operating pressure (OP) on the various quality attributes of pomelo juice, such as pH, total soluble solids (TSS), turbidity, color, total phenolic content (TPC), ascorbic acid content (AAC) and fouling mechanisms and permeate flux (J) behavior. To perform the clarification of pomelo juice, a 100 kDa membrane (polymeric) was used in a dead-end system, and the process was carried out in batch mode at OP values of 1.0, 1.5, 2.0, 2.5 and 3.0 bar. The findings revealed that increasing OP led to higher flux during ultrafiltration with limiting pressure (Plim). The limiting pressure (Plim) was anticipated to be beyond 3.0 bar due to the enzymatic pretreatment. The primary fouling mechanism during the clarification process was total pore blocking. After filtration, the resulting juice showed a significant reduction in turbidity of over 97%, while TSS was lowered by 7–17% compared to fresh juice. The pomelo juice was efficiently clarified while the pH remained stable at ∼3.8. The clarified juice showed a minor decline of 10.1–13.9% in TPC and a 10.8–16.7% reduction in AAC compared to the fresh unclarified juice. In conclusion, a pressure of 3.0 bar is recommended for conducting the ultrafiltration process in order to attain desirable flux behavior and optimum properties of the juice. [ABSTRACT FROM AUTHOR]

Although blossom and honeydew honeys are produced from different nectar sources, it is very difficult to distinguish them. In this study, physicochemical and biochemical properties were compared to distinguish honeydew and blossom honeys obtained from different botanical sources. The honeys of pine (Pinus spp.) and oak (Quercus, spp.) were used as honeydew honey, and chestnut (Castania sativa L.) and highland honey were used as blossom honey. Turbidity, specific optical rotation (SOR) [α]20, electrical conductivity (EC), CIEL* a*b color parameters, and moisture and pH were assessed as physical parameters. Proline, invertase activity, sugar composition, total phenolic and flavonoid contents, and antioxidant capacity were used as biochemical properties. It was determined that SOR values were the most important parameters in distinguishing honeydew and blossom honeys. Turbidity stands out as a crucial factor in differentiating between pine and oak honeys. Except for chestnut honey, electrical conductivity, CIE color Lab values, and sugar profiles were identified as additional distinguishing factors among the tested honeys. [ABSTRACT FROM AUTHOR]

This study aims to improve COD, NH3‐N, and turbidity removal from Bingöl's leachate using a single‐reactor integrated electrocoagulation (EC)–coal‐based powdered activated carbon (CBPAC) process under various experimental conditions. In the EC‐CBPAC process, three stainless‐steel cathodes and three aluminum electrodes were connected to the negative and positive terminals of the power supply, respectively. The initial concentrations in the leachate were 1044 mg O2/L for COD, 204 mg/L for NH3‐N, and 57 NTU (or 71.25‐mg (NH2)2H2SO4/L) for turbidity, respectively. After a 40‐min EC‐CBPAC process, with a CBPAC dosage of 5 g/L and pH of 5 for COD and turbidity, and 9.5 for NH3‐N, the optimum removal efficiencies for COD, NH3‐N, and turbidity were achieved at 92%, 40%, and 91%, respectively. When the EC process was applied without CBPAC under the same experimental conditions, the removal efficiencies of COD, NH3‐N, and turbidity were 87%, 28%, and 54%, respectively. Before and after the EC‐CBPAC process, the Brunauer–Emmett–Teller (BET) surface area, pore volume, and mean pore diameter of the CBPAC were found to be (888 m2/g, 0.498 cm3/g, and 22.28 Å) and (173 m2/g, 0.18 cm3/g, and 42.8 Å), respectively. The optimum pseudo‐first‐order (PFO) rate constants for COD, turbidity, and NH3‐N were determined to be 3.15 × 10−2, 4.77 × 10−2, and 8.8 × 10−3 min−1, respectively. With the current density increasing from 15 to 25 mA/cm2, energy consumption, unit energy consumption, and total cost increased from 68.7 to 122.4 kWh/m3, 6.948 to 15.226 kWh/kg COD, and 0.85 to 1.838 $/kg COD, respectively. Practitioner points: EC‐CBPAC process has greater COD, NH3‐N, and turbidity removal efficiency than EC process.COD and turbidity achieved their optimum disposal efficiencies at 92% and 91%, respectively, at pH 5The most efficient disposal efficiency for NH3‐N was observed to be 40% at pH 9.5.EC‐CBPAC process increased removal efficiencies for COD, NH3‐N, and turbidity by 20%, 19%, and 38%, respectively, compared with EC alone.The turbidity, NH3‐N, and COD disposal fitted PSO model due to high correlation values (R2 0.94–0.99). [ABSTRACT FROM AUTHOR]

Anthropogenic stressors such as agriculture and urbanization can increase river turbidity, which can negatively impact fish gill morphology and growth due to reduced oxygen in the benthic environment. We assessed the gill morphology, field metabolic rate (FMR), and two hypoxia tolerance metrics (oxygen partial pressure at loss of equilibrium, PO2 at LOE, and critical oxygen tension, Pcrit) of eastern sand darter (Ammocrypta pellucida), a small benthic fish listed as threatened under the Species at Risk Act in Canada, from rivers in southern Ontario. Field trials were conducted streamside in the Grand River (August 2019; mean NTU 8) and in the comparatively more turbid Thames River (August 2020; mean NTU 94) to test the effect of turbidity on each physiological endpoint. Gills were collected from incidental mortalities and museum specimens, and were assessed using hematoxylin and eosin and immunofluorescent staining. The between‐river comparison indicated that turbidity significantly increased interlamellar space and filament width but had no significant influence on other gill morphometrics or FMR. Turbidity significantly increased PO2 at LOE (i.e., fish had a lower hypoxia tolerance) but did not significantly impact Pcrit. Therefore, although turbidity influences hypoxia tolerance through LOE, turbidity levels were not sufficiently high in the study rivers to contribute to measurable changes in gill morphology or metabolism in the wild. Determining whether changes in gill morphology or metabolism occur under higherturbidity levels would help resolve the ecological importance of turbidity on species physiology in urban and agricultural ecosystems. [ABSTRACT FROM AUTHOR]

Optical Wireless Communications (OWCs) are capable of handling large data rates in the Internet of Underwater Things (IoUT) at low latency to be suitable for real-time image and video applications. This paper presents communication link feasibility via link budget to determine the link communication range for three types of line-of-sight link configurations: point-to-point, diffused, and modulating retro-reflector link. The main aim of this paper is to present a more realistic power link budget which is developed to take into account the following: LED Photo Source Lambertian radiation model, Beer-Lambert pass loss model that includes absorption and scattering effects of water types, Spherical wave propagation model, photodetector which is modeled by active area model, transmitter projection optics (PO) gain and receiver collection optics (CO) gain. Moreover, this paper considers the effects of aquatic channels 'scattering and absorption by using intensity modulation direct detection IM-DD OOK, LED and LD–PS based transmitter, and SiPM-PD based receiver. The impact of different underwater environments, transmitter, and receiver parameters will be investigated on the communication link range. Its communication range on the order of tens of meters could be achieved by the three-link configurations. It is concluded from the analysis; that the line-of-sight point-to-point provides more communication range than a diffused line of sight. A diffused line of sight is used when it is required to multicast from a node to several nodes. Modulating retro-reflector provides moderate communication range and it is used when one party has more resources than the other one on the communication link. Medium distances are achieved by up to a hundred meters by placing multiple relay nodes between the source node and the destination node. The communication range is increased as increasing the active physical area of the photodetector and the transmitted power of the photo source. The communication range in both clear sea water and clear ocean water is higher than turbid water which is less since optical water suffers from higher attenuation. By using the multi-hop concept, an extended communication link range can be achieved. [ABSTRACT FROM AUTHOR]

Several climate-driven processes take place in the Arctic fjords. These include ice-ocean interactions, changes in biodiversity and ocean circulation patterns, as well as coastal erosion phenomena. Conducting long-term oceanographic monitoring in the Arctic fjords is, therefore, essential for better understanding and predicting global environmental shifts. Here we address this issue by introducing a new hydrographic dataset from Hornsund, a fjord located in south-western part of Svalbard archipelago. Hydrographic properties have been monitored with vertical temperature, salinity and depth profiles in several lo- cations across the Hornsund fjord from 2015 to 2023. From 2016 onward dissolved oxygen and turbidity data are available for the majority of casts. The dataset contributes to the so far infrequent observations especially in spring and autumn and extends the observations typically concentrated in the central fjord to the areas adjacent to the tidewater glaciers. Because sediment discharge from glaciers and land is an inseparable part of the glacier-ocean interactions, the suspended sediment concentration in the water column as well as the daily sedimentation rate adjacent to the tidewater glaciers are monitored with regular water sampling and bottom-moored sediment traps. Here we present the planning and execution of the monitoring campaign from the collection of the data to the post-processing methods. All datasets are publicly available at the repositories referred to in the Data availability section of this manuscript. [ABSTRACT FROM AUTHOR]

This study explored the synthesis of potash alum from disposed aluminum cans for water purification. The effect of the labels on the cans on the yield of alum was also investigated as it is economically beneficial for industry. Single crystals of potash alum were obtained and characterized by powder X-ray diffraction (P-XRD) and Fourier transform infrared (FTIR) spectroscopy. Through a series of jar test experiments, the characterized alum samples were used to purify river water samples. Some of the parameters investigated include; pH, turbidity, total suspended solids (TSS), total dissolved solids (TDS), electrical conductivity (EC) and chemical oxygen demand (COD). The results show that the alum samples were able to reduce the turbidity by 100 % and substantially decrease the TSS, TDS and COD over the five-hour period of study. However, there were slight increases in acidity and EC which could be corrected by other methods [ABSTRACT FROM AUTHOR]

AlMashan, N.; Al-Attar, I., and Neelamani, S., 2024. Assessment of annual sedimentation into Failaka Marina (Kuwait) and possible solutions for reduction of siltation. Journal of Coastal Research, 40(3), 527–553. Charlotte (North Carolina), ISSN 0749-0208. Sedimentation is critical for ports, harbors, and marinas, requiring accurate assessment. Failaka Marina in Kuwait is experiencing a severe noncohesive sedimentation problem. The samples collected at the seven locations along the beach showed that the beach has a uniform grain-size diameter, meaning it is poorly graded sand. The sampling at the tip of the southern breakwater showed that the shoaling is mainly sand. The suspended-sediment concentration varies from 0.025 kg m–3 to 1.2 kg m–3, whereas the mean concentration at the marina entrance is 0.85 kg m–3. The time series of the suspended solids over a year in the seawater surrounding Failaka Island shows a range of 8 to 48,069 ppm. Such a considerable variation in suspended load is due to the massive amounts of dredging and spoil disposal at Boubyan Island and Basra Port (Iraq) when a high sediment load moves around Failaka Island with a concentration of more than 40,000 mg L–1. Annual sedimentation is about 2.35 m y–1, which is responsible for blocking the main entrance for navigation. Kuwait's Ministry of Communication allocates $4 to $6 million annually for dredging and disposal activities. This study evaluates the six marina entrance modification scenarios to determine the best scenario that achieves a measurable reduction in sedimentation rate in the Marina. Six marina breakwater modifications were studied, and annual sedimentation rates were numerically computed. The study use Coupled MIKE 21/3 to simulate hydrodynamic conditions for cohesive sediment transport in a problem area. Field data from 2015 calibrated and validated the model. The primary sediment-moving force is SE wind and sea-swell waves. Littoral drift along Failaka Island's southern coastline and high suspended-sediment concentration result in littoral drift and settling. The best scenario showed a 28% sedimentation reduction and a 26% reduction in maintenance dredging costs from the six studied scenarios. [ABSTRACT FROM AUTHOR]

The aim of this study was to develop a stable palm carotene-based emulsion using the rice protein isolate-flaxseed gum complex (RPI-FG) with different ratios (3:1, 5:1, 7:1, 9:1, 11:1). RPI achieved highest solubility at pH 12. Meanwhile, RPI-FG complex shows low turbidity value from pH 6 to 12 for all ratios. Emulsion with ratio 7:1 exhibited 33 % droplet size increment throughout 7 days storage and evenly distributed based on the microstructure images. For creaming index (CI), all emulsion shows 0 % separation on day zero except emulsion with ratio 11:1 (1.90 %) and lowest CI on day 7 was 9.05 % in ratio 3:1. Furthermore, emulsion activity index and emulsion stability index of the emulsions decreased significantly with the reduced of FG in the formulation. These results suggested that carotene-based emulsion fabricated using RPI-FG complex with ratio of 7:1 exhibited the highest emulsion stability and could be further applied in aqueous food systems. [ABSTRACT FROM AUTHOR]

The remote sensing of turbidity and suspended particulate matter (SPM) relies on atmospheric corrections and bio-optical algorithms, but there is no one method that has better accuracy than the others for all satellites, bands, study areas, and purposes. Here, we evaluated different combinations of satellites (Landsat-8, Sentinel-2, and Sentinel-3), atmospheric corrections (ACOLITE and POLYMER), algorithms (single- and multiband; empirical and semi-analytical), and bands (665 and 865 nm) to estimate turbidity and SPM in Patos Lagoon (Brazil). The region is suitable for a case study of the regionality of remote-sensing algorithms, which we addressed by regionally recalibrating the coefficients of the algorithms using a method for geophysical observation models (GeoCalVal). Additionally, we examined the results associated with the use of different statistical parameters for classifying algorithms and introduced a new metric (GoF) that reflects performance. The best performance was achieved via POLYMER atmospheric correction and the use of single-band algorithms. Regarding SPM, the recalibrated coefficients yielded a better performance, but, for turbidity, a tradeoff between two statistical parameters occurred. Therefore, the uncertainties in the atmospheric corrections and algorithms used were analyzed based on previous studies. In the future, we suggest the use of in situ radiometric data to better evaluate atmospheric corrections, radiative transfer modeling to bridge data gaps, and multisensor data merging for compiling climate records. [ABSTRACT FROM AUTHOR]

Total phosphorus (TP, a non-optical sensitivity parameter) has become the primary pollutant in the Yangtze River, the third largest river in the world. It is strongly correlated with turbidity (an optical sensitivity parameter) in rivers. In this study, we constructed a turbidity-mediated TP retrieval model using Sentinel-2 observations and field-measured daily-scale water quality. The model was successfully applied to estimate the temporal and spatial variations of TP concentration in the middle reaches of the Yangtze River (MYR) from 2020 to 2023. Our results show: (1) the model accuracy of TP concentration retrieval with turbidity is significantly higher (R2 = 0.71, MAPE = 15.78%) than that for the model without turbidity (R2 = 0.62, MAPE = 16.38%); (2) the turbidity and TP concentration in the MYR is higher in summer and autumn than in winter and spring; and (3) the turbidity and total phosphorus (TP) concentration of the Yangtze River showed a significant increase after passing through Dongting Lake (p < 0.05). [ABSTRACT FROM AUTHOR]

The water quality index (WQI) is a practical and comprehensive technique to evaluate water quality. It is often employed to assess water quality in simple terms and determine its suitability for various uses. The current study aimed to assess the temporal and spatial variation of the Al-Dujaila River. Three sites were selected for surveying from January to December 2021. The studied area starts after the AL-Kut dam and goes to the point where the river exits in the city of AL-Kut. Several physico-chemical parameters were addressed to calculate the IQ-WQI based on the Iraqi rivers maintaining limits; namely, dissolved oxygen (DO mg/ l), biological oxygen demand (BOD5 mg/l), hydrogen ion (pH), phosphate (PO4 mg/ l), nitrate (NO3 mg/ l), chloride (Cl mg/ l), sulfate (SO4-2 mg/ l), total dissolved solid (TDS mg/ l), and turbidity (Turb NTU). The concentrations of most parameters were within the standard limits, except for SO4-2, TDS, and Turb, where the highest concentrations reached 390mg/ l, 920mg/ l, and 70 NTU, respectively. The rating of the water quality index in these three sites falls under very poor water quality, where values of the IQ-WQI ranged between 83.41-89.48 in the wet season, and in the dry season, the value was 85.24-91.13. The shift of the index toward the worst conditions is related to the high concentration of TDS and SO4-2, where the standard limits for them are 500 and 200mg/ l according to the Iraqi rivers maintaining limits, respectively, which indicates pollution conditions of the river caused by the increased levels of salts. The principal component analysis (PCA) was used to visualize the data obtained to know how they interrelate in addition to extracting the most affecting parameters on water quality. [ABSTRACT FROM AUTHOR]

Microbial pollution of recreational waters leads to millions of skin, respiratory, and gastrointestinal illnesses globally. Fecal indicator bacteria (FIB) are monitored to assess recreational waters but may not reflect the presence of Staphylococcus aureus, a global leader in bacterial fatalities. Since many community‐acquired S. aureus skin infections are associated with high recreational water usage, this study measured and modeled S. aureus, methicillin‐resistant S. aureus (MRSA), and FIB (Enterococcus spp., Clostridium perfringens) concentrations in seawater and sand at six beaches in Hilo, Hawai'i, USA, over 37 sample dates from July 2016 to February 2019 using culturing techniques. Generalized linear models predicted bacterial concentrations with physicochemical and environmental data. Beach visitors were also surveyed on their preferred activities. S. aureus and FIB concentrations were roughly 6–78 times higher at beaches with freshwater discharge than at those without. Seawater concentrations of Enterococcus spp. were positively associated with MRSA but not S. aureus. Elevated S. aureus was associated with lower tidal heights, higher freshwater discharge, onsite sewage disposal system density, and turbidity. Regular monitoring of beaches with freshwater input, utilizing real‐time water quality measurements with robust modeling techniques, and raising awareness among recreational water users may mitigate exposure to S. aureus, MRSA, and FIB. Practitioner Points: Staphylococcus aureus and fecal bacteria concentrations were higher in seawater and sand at beaches with freshwater discharge.In seawater, Enterococcus spp. positively correlated with MRSA, but not S. aureus.Freshwater discharge, OSDS density, water turbidity, and tides significantly predicted bacterial concentrations in seawater and sand.Predictive bacterial models based upon physicochemical and environmental data developed in this study are readily available for user‐friendly application. [ABSTRACT FROM AUTHOR]

This study explores the visibility of phosphorescent-netting pots to snow crab (Chionoecetes opilio) using visual modeling techniques. Light emitted from such pots increases catch per unit effort, yet little is understood about the factors driving these higher catch rates. In this study, we measure pot light emission and snow crab visual acuity. Combining these data with estimates obtained in the literature for other biotic and abiotic factors, we model snow crab vision in relation to the pots. Utilizing these factors and environmental conditions, we derive a contrast ratio between the pot light and the ambient light. Findings reveal that the visibility of pot lights at 200-m depth depends primarily on solar angle (time of day) and time elapsed post-deployment. Additional factors influencing the vision of the pots include water column quality and benthic boundary layer turbidity. This study is the first to model the visual ecology of snow crab and the first to estimate snow crab visual acuity. These insights into snow crab visual ecology can potentially enhance fishing techniques, promote catch efficiency and sustainability, and help provide a path forward for visual ecology research in the fisheries science field. [ABSTRACT FROM AUTHOR]

Imaging spectroscopy allows us to identify surface materials by analyzing the spectra resulting from the light–material interaction. In this preliminary study, we analyze a pair of hyperspectral cubes acquired by PRISMA (on 20 April 2021) and EO1- Hyperion (on 4 July 2015) over the Indonesian Lusi mud eruption. We show the potential suitability of using the two sensors for characterizing the mineralogical features in demanding "wet and muddy" environments such as Lusi. We use spectral library reflectance spectra like Illite Chlorite from the USGS spectral library, which are known to be associated with Lusi volcanic products, to identify minerals. In addition, we have measured the reflectance spectra and composition of Lusi sampled mud collected in November 2014. Finally, we compare them with reflectance spectra from EO1-Hyperion and PRISMA. The use of hyperspectral sensors at improved SNR, such as PRISMA, has shown the potential to determine the mineral composition of Lusi PRISMA data, which allowed the distinction of areas with different turbidities as well. Artifacts in the VNIR spectral region of the L2 PRISMA reflectance product were found, suggesting that future work needs to take into account an independent atmospheric correction rather than using the L2D PRISMA product. [ABSTRACT FROM AUTHOR]

In this study a biobased polyurethane (PU) thermoset is investigated due to its turbidity. In contrary to the expectations, the turbidity increases with a higher amount of a low molecular weight crosslinker. Morphological aspects are investigated with SEM imaging and measurement of the effective scattering coefficient μ's. FTIR spectroscopy is applied to study the influence of the chemical structure. This is combined with multivariate data analysis to identify the relevant peaks. SEM images show spherical precipitations with increasing turbidity and a simultaneous increase in the μ's values. FTIR analysis shows a significant amount of unreacted isocyanate‐(NCO)groups and a low level of hydrogen bonding. No formation of typical hard and soft segments is detectable. Therefore, it can be concluded that the increase in polarity differences with increasing crosslinker amount disabled the mixture of the polyol and isocyanate components, resulting in the precipitation of the isocyanate. At the same time, the low molecular weight crosslinker (~200 g mol−1) can react with the NCO quickly, reducing the mobility of the polymer chain, with remaining, non‐reacted isocyanate. A proof for the correlation of the differences in the FTIR and the μ's values was found by a regression analysis with an R2 of 0.94. [ABSTRACT FROM AUTHOR]

Biodegradable solid-phase poly(vinyl alcohol)/carboxymethyl cellulose composites, which are promising to be used in pharmaceutics, agriculture, and chemical industry, have been obtained by an environmentally friendly method of "mild" mechanochemical activation without solvents and crosslinking agents. Air-dry mixtures of poly(vinyl alcohol) and carboxymethyl cellulose taken in mass ratios of 2 : 1, 1 : 1, and 1 : 2 have been subjected to a shock–shear action for 3 and 5 min (mechanical energy doses of 0.74 and 1.24 kJ/g) using an IVS-4 vibrating grinder (1500 rpm; 23.4 Hz; 0.55 kW; sample weight, 50 g; grinding bodies-to-sample mass ratio, 44 : 1). The mechanically activated samples in the form of medium powders (bulk density within a range of 600–1000 kg/m3) have been studied by the methods of scanning electron microscopy, differential scanning calorimetry, thermogravimetry, IR spectroscopy, optical microscopy, pycnometry, turbidimetry, and gravimetry. It has been found that the mechanochemical activation of an equimass mixture of poly(vinyl alcohol) and carboxymethyl cellulose at a mechanical energy dose of 1.24 kJ/g yields polymer solutions with a concentration of 1 g/dL that are rather transparent in the visible region (turbidity of 0.14 cm–1) and stable for 96 h. It has been revealed that, when being dried at 25°C, poly(vinyl alcohol) crystallizes from aqueous 1 and 2 g/dL solutions to form dendrites or crystallites after treatment at mechanical energy doses of 0.74 and 1.24 kJ/g, respectively. Polymer films of the composites have a complex morphology that includes dendritic and axialite crystalline forms. It has been found that the mechanochemical treatment stimulates the formation of crystalline forms of polymers, changes their intermolecular interaction, and affects the hydroxyl and ether groups of carboxymethyl cellulose, as well as the hydroxyl groups of poly(vinyl alcohol). [ABSTRACT FROM AUTHOR]

A novel and highly sensitive flow injection method was developed for the determination of Mebeverine. The method is based on the formation of an ion pair compound between Mebeverine hydrochloride and calcium hexacyanoferrate in an ammonium chloride medium, resulting in the formation of a whitish-yellow precipitate complex. The analysis was performed using a homemade NAG-4SX3-3D triple flow cell CFIA Analyzer. The experimental parameters were studied to optimize both the chemical and physical aspects of the method. The linear working range was obtained to be 0.01-40 mM, with an impressive correlation coefficient (r) of 0.9907. The limit of detection (LOD) was determined to be 0.349 µg/150 µl, and the repeatability of the method (RSD%) was demonstrated to be less than 1.5%. To further evaluate the performance of the newly proposed method, a comparison was conducted using the standard addition method in conjunction with a classical method. Overall, the developed flow injection method offers simplicity, sensitivity, and reliable analytical performance for the determination of Mebeverine, making it a promising alternative to the classical method. [ABSTRACT FROM AUTHOR]

Stoneworts (Charales) are green algae that represent an important food resource for many waterbird species in Europe and elsewhere. Browsing avian herbivores (e.g. swan, goose, duck and coot species) consume Charales plant vegetative parts, by head‐dipping, up‐ending or diving. A lower fibre content and longer growing season may make Charales as attractive to such herbivores as sympatric submerged higher plant species in some circumstances. Charales respond to environmental stress (e.g. drought) by producing abundant diaspores, in the form of oospores (sexual) and bulbils (asexual), both rich in starch, generating abundant food for waterbirds at critical stages in their annual migratory cycles. Waterbirds feed on these by diving (e.g. common pochard Aythya ferina and red‐crested pochard Netta rufina) or by filtering from the water column (e.g. dabbling duck species), ensuring dispersal of sexually produced and vegetative diaspores locally (because of predator swamping) and remotely (through endo‐ and ectozoochorous dispersal by long‐distance migratory waterbirds). Greater invertebrate density and diversity associated with Charales canopies enhances their attractiveness over other submerged macrophyte beds to diving predators [e.g. tufted duck Aythya fuligula, common pochard and Eurasian coot Fulica atra (hereafter coot)]. Fish fry preying on these invertebrates use such vegetation as predator cover, in turn providing prey for avian piscivores such as grebes and cormorants. Abundant Charales contribute to maintaining a transparent water column due to canopy density, nutrient effects, dampening of sedimentation/remobilisation of suspended matter and nutrients and allelopathic effects on other plants (especially phytoplankton). Shallow, relatively eutrophic waters can flip between clear‐water high‐biodiversity (where Charales thrive) and turbid species‐poor depauperate stable states (lacking Charales). Shifts between turbid conditions and rich submerged Charales beds have profound elevating effects on aquatic diversity, to which waterbirds show rapid aggregative responses, making them ideal indicator species of ecological change; in the case of Charales specialists (such as red‐crested and common pochard), indicators of the presence and abundance of these plants. Large‐bodied colonial nesting birds (e.g. cormorants, gulls, heron and egrets) aggregating along lake shores contribute high N and P loadings to water bodies sensitive to such external and internal inputs and can cause local eutrophication and potential loss of Charales. Despite variation from complete seasonal removal of Charales biomass to undetectable grazing effects by herbivorous birds, evidence suggests little effect of avian grazing on biomass accumulation or the stability of community composition (under otherwise stable conditions), but we urge more research on this under‐researched topic. We also lack investigations of the relative foraging profitability of different Charales organs to waterbirds and the degree of viability of gyrogonites (fertilised and calcified oospores), vegetative bulbils and plant fragments after passage through the guts of waterbirds. We especially need to understand better how much the carbonate armour of these organs affects their viability/dispersal via waterbirds and urge more research on these neglected plants and their relationships and interactions with other organisms in the aquatic biota. [ABSTRACT FROM AUTHOR]

Degradation of water quality is an emerging issue in many developing countries. In this context, industrial and domestic effluents heavily contaminate the coast of Moknine Continental Sebkha in Tunisia. The present study aimed to biomonitor the seawater quality of the Moknine Continental Sebkha coast using physicochemical and ecotoxicological approaches. The ecotoxicological assessment was performed using three species representing different trophic levels, namely Vibrio fischeri, Selenastrum capricornutum, and Lepidium sativum. In the physicochemical analysis such as BOD (biochemical oxygen demand), COD (chemical oxygen demand), TSS (total suspended solids), TOC (total organic carbon), NO3 ( (nitrate), AOX (adsorbable organic halogen), the recorded levels of pH and total suspended solids did not comply with the Tunisian standard (NT.09.11/1983). The ecotoxicological data confirmed that the tested water samples displayed toxicity to two test indicators L. sativum and S. capricornutum. A targeted chemical screening of the Moknine Continental Sebkha coast previously performed revealed the presence of total mercury, four phthalate acid esters, and one non-phthalate plasticizer, a fact that could explain the observed ecotoxicological effects and therefore might harm the biotic area and the health of the surrounding population. [ABSTRACT FROM AUTHOR]

Chitosan, chitosan-moringa seed powder, and chitosan-moringa seed powder-bentonite composite films were fabricated by solvent casting method. The texture and the color of the chitosan films changed in the presence of moringa seed powder and bentonite. Moringa seed powder decreased the tensile strength of the films, whereas bentonite improved the tensile strength of the films when its concentration was below 15 wt%. All the films could efficiently remove turbidity from model turbid water - prepared by dispersing kaolin in water. A marked increase in turbidity coagulation was observed when moringa seed powder was incorporated into the chitosan film. Films with 15 wt% moringa seed powder could remove 73% in 3 h, whereas chitosan film alone removed 53% in 3 h. Further enhancement of turbidity removal efficacy was observed when bentonite was incorporated into the films along with the moringa seed powder. Films with 15 wt% moringa seed powder and 10 wt% bentonite removed 83 and 96% turbidity in 3 and 12 h, respectively. Furthermore, these films could be reused several times. The films with the above composition were tested for turbidity settlement for five cycles. In the 5th cycle, the films could remove 85% turbidity without undergoing any breakage. [ABSTRACT FROM AUTHOR]

Research has been conducted to make microemulsion preparations from virgin coconut oil (VCO) and secang wood extract. The purpose of this study was to determine the characteristics of secang wood extract with ethanol solvent, determine the Hydrophilic Lipophilic Balance (HLB) value of a mixture of three surfactants that can form the most stable microemulsion preparations, and determine the most optimal variation in the concentration of secang wood extract in secang microemulsion formulations. This study began with the manufacture of secang wood ethanol extract from secang wood powder and 96% ethanol, then tested for flavonoid levels. Furthermore, VCO microemulsions in a mixture of water with secang extract are made with variations in HLB values, namely 12, 13, 14, and 15. Microemulsions with HLB variations were tested for stability through organoleptical observations and turbidity values by storage treatment at room temperature, heating, and centrifugation. Microemulsions were also tested for free fatty acid (FFA) levels. After that, the preparation of microemulsions with the most stable HLB is carried out with variations in the concentration of secang wood extract in the formulation. Microemulsions with extract variations were tested for stability through organoleptical observation and turbidity values after 24 hours, heating, and centrifugation. Microemulsions with optimal concentrations of secang wood extract were tested for antioxidant activity. The secang extract produced from the extraction was reddish-brown in color and had total flavonoids equivalent to 230.6 mg QE/g samples. The most stable microemulsion from this study is a microemulsion with an HLB value of 15 with a ratio of water:extract:VCO:surfactant which is 65:2,5:2,5:30. The microemulsion features transparent red, 1 phase, and smells like Tween 80 with turbidity value below 1% during storage, heating, and centrifugation with microemulsion FFA value of 0.53%. Based on variations in the concentration of secang wood extract, the higher the concentration of the extract, the more unstable the microemulsion produced. The 3% secang extract microemulsion is the most optimal microemulsion with antioxidant activity (IC50) of 1.4573±0.2694 mg/mL. [ABSTRACT FROM AUTHOR]

The object of the study is the process of purifying natural waters using coagulants of natural and industrial origin. The subject of the study is the analysis of the effectiveness of coagulants of natural and industrial origin. Today, there is great interest in finding alternative methods of water purification that would be more economical and environmentally friendly. The availability of clean and safe water is especially important during times of martial law. Coagulants of natural origin can be an affordable and effective means of water purification and disinfection. One of the important advantages is availability, which indicates the possibility of becoming an alternative to chemical coagulants. Thus, there is a need to study the possibility of using natural coagulants both on an industrial scale and in emergency conditions. This study presents a characterization of existing coagulants of natural origin, an analysis of the effectiveness of their use, comparison with chemical analogues, as well as an analysis of the effectiveness of using Moringa oleifera as a natural coagulant. During the work, two coagulants were synthesized from red mud from aluminium production. A comparative analysis of coagulants synthesized from red mud, Moringa oleifera, aquatone and aluminium sulphate was carried out. All reagents were used to remove turbidity and other impurities. The studies were carried out 3 times in different seasons of the year. All results were compared to determine the most effective coagulant and its dose. As a result, it was found that all of these coagulants can be used and reduce water treatment costs at local water treatment plants. The natural coagulant can be used in areas where there is no access to a central water supply, especially in war zones. [ABSTRACT FROM AUTHOR]

The paper considers a dispersive geological medium (seismically turbid medium, as defined by A.V. Nikolaev), which is in a stress–strain state. Results of studies on the joint monitoring of seismic effects and radon emanation in various geological environments are presented. It is concluded that the turbidity of the medium, as a statistical characteristic, can be generalized in terms of other media parameters, such as permeability. A stable connection between radon emanation and dynamic processes occurring in a geological environment and caused by external influences has been established. The concentration of radon can also reflect the degree of enrichment of the environment by underground fractures. Consequently, saturation of the environment with radon provides information about the presence of disturbances in a geological environment in the form of cracks and a stress–strain state of the medium before and after seismic loadings. Radon observations make it possible to assess a continuity of the environment and the possibility of leaching in natural conditions. Therefore, it could be efficiently used for underground leaching efficiency assessment. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the use of sweet potato as a local source of enzymatic extract for the saccharification of sorghum mash. Box-Behnken designs were employed to determine the optimal conditions for extracting crude enzymes and saccharifying Safrari sorghum mash. The optimal conditions for maximizing enzymatic activity were found to be a mass-to-volume ratio of 0.1, an extraction time of 210 min, and a temperature of 60°C. The theoretical and experimental enzymatic activities under these conditions were 23.83 U/mg and 23.49 U/mg, respectively. The extraction of enzymes under these optimal conditions resulted in wort with physicochemical parameters within the following ranges: turbidity (0.79 to 4.52 NTU), pH (5.40 to 8.85), brix (14.80 to 17.50°B), reducing sugars (0.17 to 0.2114 mg/mL), and titratable acidity (3.54 to 5.24 g/L). These findings demonstrate that the extract from Ipomoea batatas contains enzymes that can be effectively used in the mashing process of malted Safrari sorghum. [ABSTRACT FROM AUTHOR]

Behavioural plasticity allows organisms to respond to environmental challenges on short time scales. But what are the ecological and evolutionary processes that underlie behavioural plasticity? The answer to this question is complex and requires experimental dissection of the physiological, neural and molecular mechanisms contributing to behavioural plasticity as well as an understanding of the ecological and evolutionary contexts under which behavioural plasticity is adaptive. Here, we discuss key insights that research with Trinidadian guppies has provided on the underpinnings of adaptive behavioural plasticity. First, we present evidence that guppies exhibit contextual, developmental and transgenerational behavioural plasticity. Next, we review work on behavioural plasticity in guppies spanning three ecological contexts (predation, parasitism and turbidity) and three underlying mechanisms (endocrinological, neurobiological and genetic). Finally, we provide three outstanding questions that could leverage guppies further as a study system and give suggestions for how this research could be done. Research on behavioural plasticity in guppies has provided, and will continue to provide, a valuable opportunity to improve understanding of the ecological and evolutionary causes and consequences of behavioural plasticity. [ABSTRACT FROM AUTHOR]

Bathymetric data represents estimated seafloor topography and aids in understanding the intricacies of earth and ocean interaction processes. The General Bathymetric Chart of the Oceans (GEBCO) released the GEBCO_2023 gridded bathymetric data as an interim dataset in connection with the ambitious task of producing the definitive ocean floor map for the globe by 2023. Evaluating the data of scientific importance is essential to ensure its fitness for the applications; however, the procedure needs qualified reference data of higher accuracy for comparison. This article discusses the methods and results of performance validation on GEBCO_2023 using the seafloor obtained from the ICESat-2 geolocated photons as a reference. The validation was carried out at three test sites containing shallow waters in the Indian Ocean. In two of the test sites, where the coastal waters have minimal influence from the continental sediment flux, the trend of the seafloor from both the data sources is similar, and the quantified accuracy of GEBCO_2023 in terms of RMSE is less than 3 m. In the extent of the third test site, where mostly perennial turbidity prevails, the accuracy of the GEBCO's seafloor depth in terms of RMSE and MAE is in the range of 5–6 m, with underestimation of the seafloor. The reasons for the errors in the GEBCO_2023 grid were analyzed based on the associated metadata, namely, the Type-Identifier grid that informs the source of depth data for a given grid cell. In summary, the GEBCO_2023 grid is the best available and resourceful bathymetric data in the present scenario where challenges and complications exist for mapping the ocean surface besides technological advancements. [ABSTRACT FROM AUTHOR]

Legumes are a cost-effective source of proteins and abundant starch, a biodegradable substance, providing human nutrition and serving various food sectors globally. Some of the neglected (underutilised) legumes can also be used as the cheapest source of starch. Therefore, the present study was conducted to determine the physicochemical characteristics of jack bean (Canavalia ensiformis) starch - a legume not widely known so underutilised. The starch was isolated from the bean by standard method to study its various properties. One-way analysis of variance was employed to verify a significant difference at the 5% significance level. The jack bean yielded 30.98% of starch. The starch's moisture, ash, fat, protein, fiber, and carbohydrate content were 9.67%, 0.19%, 0.27%, 0.56%, 0.27%, and 89.28% respectively. The physicochemical properties were also determined. The apparent and total amylose contents were 43.82% and 47.78%, respectively, with 7.66% of amylose leaching at 95° C. The water and oil absorption capacities were 2.31 and 2.56 g/g, respectively, while emulsion capacity and stability were 62.30 and 71.38 %, respectively. The solubility and swelling power of jack bean starch increased with temperature from 55 to 95°C. The effect of starch concentrations (6, 8, and 10%) on freeze-thaw stability revealed that water expelled decreased as starch content increased. Nevertheless, a comprehensive investigation has not been conducted into the distinct functional characteristics and other attributes of jack bean starch. This study could provide new opportunities for conventional starch industries that rely on starch from sources like cereals, tubers, and rhizomes. [ABSTRACT FROM AUTHOR]

Summary: Silver carp myofibrillar proteins (MP) with different moleculars states were constructed by the addition of NaCl and fracture degree of muscle fibres. Results showed that salt‐dissolved MP (P+) under unfrozen and oxidised state showed higher oxidation degree with higher carbonyl (3.42 nmol mg−1) and dityrosine contents (25.98 a.u.) (P < 0.05) compared with saltless‐polymeric MP (P) and salt‐induced swelling MP (F+) due to addition of salt and broken muscle fibres. After oxidative and freeze–thaw process, P+ group also exhibited more cross‐linking as evidenced by turbidity (0.73), solubility (64.96%) and SDS‐PAGE, but unordered aggregates in P group increased probably due to severe frozen denaturation. Moreover, F+ group of salt‐induced swelling MP from intact muscle fibres suffered less structural damages with higher fluorescence intensity (668.41 a.u.) and higher α‐helix contents (15.56%). Overall, Fish‐ Hua of salt‐dissolved MP had a higher oxidation level and NaCl contributed to improve freeze–thaw stability of MP during freeze–thaw process. [ABSTRACT FROM AUTHOR]

The timely and accurate monitoring of water quality via remote sensing is of great significance to water environment protection. However, the relationship between water quality parameters and surface reflectance is not a simple linear one. BP neural network and Support Vector Machine (SVM) have been widely used in water quality inversion for their nonlinear simulation characteristics, yet traditional BP neural network is perplexed by slow convergence and being easy to fall into local optimum, while SVM is greatly affected by penalty coefficient and kernel function parameter. Here, a coupled model using Sparrow Search Algorithm (SSA) to optimize BP neural network and SVM is proposed to retrieve water quality parameters of conductivity and turbidity in Yunlong Lake from Sentinel-2 images. SSA is used to optimize the parameters of BP neural network and SVM, the model weight is calculated based on verification set MAE, and the final inversion results are obtained after the weighted calculation of output layer of SSA-BP and SSA-SVM model test group. And comparisons are carried out between the proposed SSA-BP-SVM model and BPNN, SVM, SSA-BP, and SSA-SVM models. The results show that, the sensitive bands of Sentinel-2 image to conductivity and turbidity are visible light and shortwave infrared; the proposed model of SSA-BP-SVM is more precise with the R² of the inverted conductivity and turbidity being 0. 92 and 0. 89, respectively; the Yunlong Lake is a typical urban water body with conductivity being greatly affected by the drainage from upstream water treatment plant and turbidity being greatly affected by particulate pollutants from social production activities. The proposed SSA-BP-SVM model has good application potential in water quality inversion from Sentinel-2 image, which can provide technical support for water quality monitoring and protection of Yunlong Lake. [ABSTRACT FROM AUTHOR]

Computer vision (CV) technologies have been applied extensively in turbid water assessment. However, the accuracies of CV to detect turbidity is limited by several factors such as inferior image quality and adoptation of traditional machine learning (MsL). Several past studies have shown that the accuracy of CV to detect turbidity can be enhanced by employing image pre-processing and artificial intelligence (AI). Therefore, this study proposes a combined CV and convolution neural network (CNN) approach for turbid water classification in accordance with national water quality standards. A total of 71 turbid water samples in the range of 0–100 nephelometry turbidity units (NTU) were prepared from a mixture of 1000 NTU stock Formazine solution and distilled water. Digital images of water samples were acquired with the Asus Zenfone Go smartphone and nephelometry principle. Synthetic minority oversampling technique (SMOTE) was employed for image pre-processing, synthesis, and augmentation. Classification models were developed with Keras CNN architecture and TensorFlow framework. Two national water standards referred to were Malaysia National Water Quality Standard Class I (NWQS-C1) and France Système D'évaluation de la Qualité des cours d'EAU bleu aptitude (SEQ-EAU-b). The proposed CV-CNN approach was successfully implemented with 94.34–98.42% accuracy. The accuracy of CNN was slightly higher when trained with color images (98.42%) than with grayscale images (94.34%). This study demonstrated that CV and CNN are excellent tools for water quality assessment, especially for classifying water turbidity. [ABSTRACT FROM AUTHOR]

In the mineral processing engineering, ultrasound is usually used to modify reagents to improve the flotation. The study analyses the effects of the modified kerosene on the flotation of flake graphite. The outcomes demonstrate that the modified kerosene can substantially improve flake graphite's floatation efficiency. In comparison to unmodified kerosene, the dosage of modified kerosene can be reduced while the recovery of graphite remains the same. Furthermore, the effect of modified kerosene was evaluated using various detection techniques including particle size distribution measurement, contact angle tests, turbidity tests, and cryo-scanning electron microscopy (Cryo-SEM). The findings indicate that ultrasound modification significantly reduces the size of kerosene to 1–2 μm droplets and improves their dispersion in the aqueous solution. The enhanced dispersion and reduced droplets size of modified kerosene led to a better interaction between kerosene and the surface of flake graphite minerals. As a result, the consumption of kerosene was reduced, but the graphite flotation efficiency was improved. [ABSTRACT FROM AUTHOR]

Research has been conducted to make microemulsion preparations from virgin coconut oil (VCO) and secang wood extract. The purpose of this study was to determine the characteristics of secang wood extract with ethanol solvent, determine the Hydrophilic Lipophilic Balance (HLB) value of a mixture of three surfactants that can form the most stable microemulsion preparations, and determine the most optimal variation in the concentration of secang wood extract in secang microemulsion formulations. This study began with the manufacture of secang wood ethanol extract from secang wood powder and 96% ethanol, then tested for flavonoid levels. Furthermore, VCO microemulsions in a mixture of water with secang extract are made with variations in HLB values, namely 12, 13, 14, and 15. Microemulsions with HLB variations were tested for stability through organoleptical observations and turbidity values by storage treatment at room temperature, heating, and centrifugation. Microemulsions were also tested for free fatty acid (FFA) levels. After that, the preparation of microemulsions with the most stable HLB is carried out with variations in the concentration of secang wood extract in the formulation. Microemulsions with extract variations were tested for stability through organoleptical observation and turbidity values after 24 hours, heating, and centrifugation. Microemulsions with optimal concentrations of secang wood extract were tested for antioxidant activity. The secang extract produced from the extraction was reddish-brown in color and had total flavonoids equivalent to 230.6 mg QE/g samples. The most stable microemulsion from this study is a microemulsion with an HLB value of 15 with a ratio of water:extract:VCO:surfactant which is 65:2,5:2,5:30. The microemulsion features transparent red, 1 phase, and smells like Tween 80 with turbidity value below 1% during storage, heating, and centrifugation with microemulsion FFA value of 0.53%. Based on variations in the concentration of secang wood extract, the higher the concentration of the extract, the more unstable the microemulsion produced. The 3% secang extract microemulsion is the most optimal microemulsion with antioxidant activity (IC50) of 1.4573±0.2694 mg/mL. [ABSTRACT FROM AUTHOR]

Atmospheric turbidity exhibits substantial spatial–temporal variability due to factors such as aerosol emissions, seasonal changes, meteorology, and air mass transport. Investigating atmospheric turbidity is crucial for climatology, meteorology, and atmospheric pollution. This study investigates the variation in atmospheric turbidity over a tropical location in Nigeria, utilizing the Ångström exponent (α), the turbidity coefficient (β), the Linke turbidity factor (TL), the Ångström turbidity coefficient (βEST), the Unsworth–Monteith turbidity coefficient (KAUM), and the Schüepp turbidity coefficient (SCH). These parameters were estimated from a six-month uninterrupted aerosol optical depth dataset (January–June 2016) and a one-year dataset (January–December 2016) of solar radiation and meteorological data. An inverse correlation (R = −0.77) was obtained between α and β, which indicates different turbidity regimes based on particle size. TL and βEST exhibit pronounced seasonality, with higher turbidity during the dry season (TL = 9.62 and βEST = 0.60) compared to the rainy season (TL = 0.48 and βEST = 0.20) from May to October. Backward trajectories and wind patterns reveal that high-turbidity months align with north-easterly air flows from the Sahara Desert, transporting dust aerosols, while low-turbidity months coincide with humid maritime air masses originating from the Gulf of Guinea. Meteorological drivers like relative humidity and water vapor pressure are linked to turbidity levels, with an inverse exponential relationship observed between normalized turbidity coefficients and normalized water vapor pressure. This analysis provides insights into how air mass origin, wind patterns, and local climate factors impact atmospheric haze, particle characteristics, and solar attenuation variability in a tropical location across seasons. The findings can contribute to environmental studies and assist in modelling interactions between climate, weather, and atmospheric optical properties in the region. [ABSTRACT FROM AUTHOR]

Herbivorous fishes, and the productivity of algal turfs, are widely viewed as central to the functioning of coral reefs. This understanding is largely based on clear-water reefs. Our knowledge of herbivorous fishes and the nature of their nutritional resources on turbid reefs, by contrast, remains relatively limited. We therefore explored the nature of herbivorous fishes and the epilithic algal matrix (EAM) on turbid coral reefs across the Dampier Archipelago in northern Western Australia. We conducted comprehensive surveys of herbivorous fish abundances across natural turbidity gradients. Moreover, we quantified the trophodynamic functioning of herbivorous fishes relative to EAM structure and productivity. We revealed a clear relationship between turbidity gradients and herbivorous fish abundance, with herbivorous fishes being virtually absent from high turbidity reefs. Across the Dampier Archipelago, EAMs were typified by sediment-laden turfs with a limited propensity to deliver nutritional resources to fishes, while the productivity (i.e. the capacity for individuals to grow and produce new biomass) of herbivorous fishes was low and a fraction of that documented on clear-water reefs in the Indo-Pacific. Given the tight coupling between herbivorous fishes and their nutritional resources, these findings imply bottom-up nutrient resource limitation, which is likely due to reduced light levels and sediment-laden conditions inhibiting EAM productivity on turbid reefs. Our results suggest that EAM-based trophic pathways may be particularly unproductive on turbid reefs, with this energetic pathway playing a limited role in reef functioning compared to reefs in clear water. [ABSTRACT FROM AUTHOR]

Salivary turbidity is a promising indicator for evaluating oral hygiene. This study proposed a wearable mouthguard-type sensor for continuous and unconstrained measurement of salivary turbidity. The sensor evaluated turbidity by measuring the light transmittance of saliva with an LED and a phototransistor sealed inside a double-layered mouthguard. The sensor was also embedded with a Bluetooth wireless module, enabling the wireless measurement of turbidity. The mouthguard materials (polyethylene terephthalate-glycol and ethylene-vinyl acetate) and the wavelength of the LED (405 nm) were experimentally determined to achieve high sensitivity in salivary turbidity measurement. The turbidity quantification characteristic of the proposed sensor was evaluated using a turbidity standard solution, and the sensor was capable of turbidity quantification over a wide dynamic range of 1–4000 FTU (formazine turbidity unit), including reported salivary turbidity (400–800 FTU). In vitro turbidity measurement using a saliva sample showed 553 FTU, which is equivalent to the same sample measured with a spectrophotometer (576 FTU). Moreover, in vivo experiments also showed results equivalent to that measured with a spectrophotometer, and wireless measurement of salivary turbidity was realized using the mouthguard-type sensor. Based on these results, the proposed mouthguard-type sensor has promising potential for the unconstrained continuous evaluation of oral hygiene. [ABSTRACT FROM AUTHOR]

Information on habitat transitions is critical to understand whether efforts to manage the freshwater phase of juvenile green sturgeon (Acipenser medirostris) rearing habitats are feasible or beneficial. We implanted microacoustic transmitters in naturally produced age-0 juvenile green sturgeon in the Sacramento River to evaluate residency, general spatial distribution, movement rates, and downstream migration patterns over 300 river kilometers. Furthermore, we investigated whether changes in three environmental variables (discharge, turbidity, and water temperature) were associated with the beginning of movements resulting in the transition from riverine to brackish waters during their outmigration to the Sacramento-San Joaquin Delta Estuary. We captured 183 juvenile green sturgeon by trawl of which 88 were implanted with microacoustic tags. An additional 10 individuals were collected and tagged from the Red Bluff Diversion Dam rotary-screw traps. Linear mixed models showed that individuals caught by trawl had longer upper river residence times, post-tagging, than those caught by trap. Intergate velocity models showed that trap-caught individuals relocated at higher upper river reach velocities than trawl-caught fish, but there were no differences between trap- and trawl-caught fish within the middle or lower reach. Detections showed that juvenile green sturgeon began the downstream transition to brackish water habitat when discharge and turbidity increased. Temperature was not found to significantly influence the initiation of downstream migration. Both continuous and stepped downstream migration patterns were observed in each of the four cohorts, with smaller individuals being more likely to exhibit stepped migration. These data provide information that was previously unknown about the life history of the southern distinct population segment of the North American green sturgeon and can be utilized to assist with water resource management and recovery of this threatened fish species. [ABSTRACT FROM AUTHOR]

Uncrewed-Aerial Vehicles (UAVs) and hyperspectral sensors are emerging as effective alternatives for monitoring water quality on-demand. However, image mosaicking for largely featureless coastal water surfaces or open seas has shown to be challenging. Another pertinent issue observed is the systematic image misalignment between adjacent flight lines due to the time delay between the UAV-borne sensor and the GNSS system. To overcome these challenges, this study introduces a workflow that entails a GPS-based image mosaicking method for push-broom hyperspectral images, together with a correction method to address the aforementioned systematic image misalignment. An open-source toolkit, CoastalWQL, was developed to facilitate the workflow, which includes essential pre-processing procedures for improving the image mosaic's quality, such as radiometric correction, de-striping, sun glint correction, and object masking classification. For validation, UAV-based push-broom hyperspectral imaging surveys were conducted to monitor coastal turbidity in Singapore, and the implementation of CoastalWQL's pre-processing workflow was evaluated at each step via turbidity retrieval. Overall, the results confirm that the image mosaicking of the push-broom hyperspectral imagery over featureless water surface using CoastalWQL with time delay correction enabled better localisation of the turbidity plume. Radiometric correction and de-striping were also found to be the most important pre-processing procedures, which improved turbidity prediction by 46.5%. [ABSTRACT FROM AUTHOR]

Turbidity is commonly monitored as an important water quality index. Human activities, such as dredging and dumping operations, can disrupt turbidity levels and should be monitored and analysed for possible effects. In this paper, we model the variations of turbidity in Dublin Bay over space and time to investigate the effects of dumping and dredging while controlling for the effect of wind speed as a common atmospheric effect. We develop a Vector Auto-Regressive Integrated Conditional Heteroskedasticity (VARICH) approach to modelling the dynamical behaviour of turbidity over different locations and at different water depths. We use daily values of turbidity during the years 2017–2018 to fit the model. We show that the results of our fitted model are in line with the observed data and that the uncertainties, measured through Bayesian credible intervals, are well calibrated. Furthermore, we show that the daily effects of dredging and dumping on turbidity are negligible in comparison to that of wind speed. [ABSTRACT FROM AUTHOR]

In mineral processing operations, it is essential to effectively remove the fine particles in slime and tailings slurry with appropriate methods. In this study, a unique two-stage flocculation scheme was developed for achieving effective separation of fine kaolinite particles from water by polyacrylamide. The slurry turbidity and flocculation kinetic parameters were used to characterize the effect of the dosing ratio between the first and second stage on the kaolinite flocculation behavior and settling rate. The results showed that the maximum kaolinite settling rate and the minimum turbidity of slurry supernatant was achieved when 60% and 40% polyacrylamide was added in the first and second stage, respectively. Focused beam reflectometer (FBRM) and particle video microscope (PVM) results showed that the flocs formed in the first stage of dosing were large in size but small in fractal dimension and no significant sedimentation was observed. The second stage of dosing produced large size of flocs with large fractal dimension, which settled fast in slurry. Fourier transform infrared spectroscopy (FTIR) results showed that polyacrylamide was mainly adsorbed on the surface of kaolinite by hydrogen bonding and kaolinite particle flocculation was achieved by trapping and coiling of the polymer chain structure. The two-stage dosing process accomplished effective flocculation and rapid settlement of fine kaolinite particles. The findings from this study provide a feasible approach for mining companies to optimize the flocculation and sedimentation of fine particles. [ABSTRACT FROM AUTHOR]

Purpose: This study is focused on monitoring process parameters and quality attributes of aluminum phosphate (AlPO4) using multiple in-line probes incorporated into an industrial-scale adjuvant suspension manufacturing unit. Methods: The manufacturing of aluminum adjuvant suspension was monitored at manufacturing scale using conductivity, turbidity, infrared, and particle sizing and count probes to follow the continuous evolution of particle formation and size distribution, and the reaction kinetics during the synthesis of AlPO4. Results: The data showed that AlPO4 forms large particles at the early stages of mixing, followed by a decrease in size and then stabilization towards the later stages of mixing and pH adjustment. The results provided a complementary view of process events and assisted in optimizing several parameters, e.g., flow rate of reactants AlCl3 and Na3PO4 solutions, mixing rate, pH, and conductivity of AlPO4, as well as adjuvant quality attribute such as particle size, thus streamlining and shortening the process development stage. Conclusion: The results of this study showed the usefulness of the in-line probes to automate continuous assessment of AlPO4 batch-to-batch consistency during in-house adjuvant production at the industrial scale. [ABSTRACT FROM AUTHOR]