Comparing the Efficacy of 5% EMLA Cream and 20% Benzocaine Gel on Gingival Tissue Surrounding Non-Carious Cervical Lesions for Reduction of Pain Following Rubber Dam Clamp Placement: A Split-Mouth Randomized Clinical Trial.

Aim The aim of this study was to evaluate the effectiveness of 5% eutectic mixture of local anesthetics (EMLA) cream and 20% benzocaine gel in reduction of pain during rubber dam clamp placement in the treatment of non-carious cervical lesions (NCCLs). Methodology In this split-mouth single-blind randomized clinical trial, 50 adult participants were selected from the outpatient department. The test group was treated using 5% EMLA cream for three minutes, and visual analog scale (VAS) scores were recorded. The comparison group was treated using 20% benzocaine gel and procedure was repeated as that in the test group. After recording the VAS scores, NCCLs in both the groups were restored using composite restoration. Results In the included 50 participants, 70% were males, with an age group of 31-67 years. The mean VAS score at 3 minutes in EMLA group was significantly lower than that in benzocaine group. Conclusion Application of 5% EMLA cream for 3 minutes showed greater pain reduction during rubber dam clamp placement as compared to 20% benzocaine gel in adult patients with NCCLs.

Neurocognitive performance of patients undergoing intravenous versus oral opioid agonist treatment: a prospective multicenter study on three-month treatment effects.

Introduction: The first-line treatment for opioid dependence is opioid agonist treatment (OAT) with oral opioids. However, in some cases, treatment with intravenous diacetylmorphine (IV-DAM) is indicated. Research on neurocognitive impairments and treatment effects of OAT - particularly with IV-DAM - on neurocognitive functioning, is scarce. The current study is the first to investigate the neurocognitive performance of individuals on OAT with IV-DAM. Using a prospective study design with two timepoints of measurement, the first aim was to assess the nature and extent of neurocognitive functioning in individuals with opioid dependence by comparing participants' neurocognitive performance with normative data of the general population on admission to treatment (baseline) and after an initial three-month period of OAT (study end). The second aim was to examine whether and to what extent neurocognitive performance would improve after three months on OAT. The third aim was to investigate whether, and if so, to what extent the treatment method (IV-DAM vs. oral opioids) would lead to higher neurocognitive improvements at study end. Methods: Forty-seven opioid-dependent individuals (baseline; 33 individuals at study end) participated in this study (mean age: 34.3 years; 27.7% female). Participants underwent neuropsychological testing with a battery of 12 tests covering different neurocognitive domains, including attention, memory, and executive functions. Results: Compared to normative data, opioid-dependent individuals showed impairments in almost every test both at baseline and at study end. At baseline, neurocognitive performance did not differ between individuals receiving IV-DAM or oral opioids for OAT. Compared to baseline, the neurocognitive performance did neither improve nor deteriorate after three months of treatment with neither IV-DAM nor oral opioids. However, a trend towards improvement was found for the memory domain. Discussion: Given that neurocognitive impairments should be considered in treatment planning and therapeutic interventions. Since a reduced cognitive performance may affect both the treatment outcome and the therapeutic relationship unfavorably, specific neurocognitive training at the beginning of treatment should be considered.

Assessing ecosystem health: A preliminary investigation of the gosikhurd dam ecosystem structure and functioning, an appraisal based on ecological modelling, India.

This study aims to comprehensively understand the Gosikhurd Dam ecosystem (GDE) ecosystem by employing the Ecopath with Ecosim software (version 6.6.5) to construct a trophic mass balancing model. This model consisted of 16 functional groups of organisms, and their interactions and trophic levels were explored. The study focuses on various performance indicators to assess the ecosystem's maturity and complexity. To achieve these objectives, monthly fish samples were collected from June 2022 to May 2023. Performance indicators such as the connectance index (CI), system omnivory index (SOI), Finn's cycling index (FCI), mean path length (FML), ascendency, overhead, and Shannon diversity index were calculated to assess ecosystem maturity and complexity. The Finn's cycling index (FCI) and the mean path length (FML) were calculated as 1.81 and 2.20, respectively, indicating the ecosystem's responsiveness to environmental changes and overall system health and stability. Ascendency and overhead values were also analysed, with ascendency being relatively higher (41.58%), reflecting a system that utilises less than half of its total capacity. The overhead value (58.42%) indicated that the ecosystem is relatively stable and capable of adapting to external perturbations. Furthermore, the Shannon diversity index was 1.67, illustrating less diversity and validating the ecosystem's immaturity. The study identifies critical species and their roles in shaping the ecosystem dynamics, highlighting the importance of zooplankton, zoobenthos, and tilapia as keystone species. These indices propound that GDE is in its developmental stage and lacks complexity compared to mature ecosystems. The findings provide valuable insights into the current state of the ecosystem and can guide future management and conservation efforts.

Size-dependent effects of dams on river ecosystems and implications for dam removal outcomes.

Understanding the relationship between a dam's size and its ecological effects is important for prioritization of river restoration efforts based on dam removal. Although much is known about the effects of large storage dams, this information may not be applicable to small dams, which represent the vast majority of dams being considered for removal. To better understand how dam effects vary with size, we conducted a multidisciplinary study of the downstream effect of dams on a range of ecological characteristics including geomorphology, water chemistry, periphyton, riparian vegetation, benthic macroinvertebrates, and fish. We related dam size variables to the downstream-upstream fractional difference in measured ecological characteristics for 16 dams in the mid-Atlantic region ranging from 0.9 to 57 m high, with hydraulic residence times (HRTs) ranging from 30 min to 1.5 years. For a range of physical attributes, larger dams had larger effects. For example, the water surface width below dams was greater below large dams. By contrast, there was no effect of dam size on sediment grain size, though the fraction of fine-grained bed material was lower below dams independently of dam size. Larger dams tended to reduce water quality more, with decreased downstream dissolved oxygen and increased temperature. Larger dams decreased inorganic nutrients (N, P, Si), but increased particulate nutrients (N, P) in downstream reaches. Aquatic organisms tended to have greater dissimilarity in species composition below larger dams (for fish and periphyton), lower taxonomic diversity (for macroinvertebrates), and greater pollution tolerance (for periphyton and macroinvertebrates). Plants responded differently below large and small dams, with fewer invasive species below large dams, but more below small dams. Overall, these results demonstrate that larger dams have much greater impact on the ecosystem components we measured, and hence their removal has the greatest potential for restoring river ecosystems.

Study on the Shear Strength and Erosion Resistance of Sand Solidified by Enzyme-Induced Calcium Carbonate Precipitation (EICP).

Sand solidification of earth-rock dams is the key to flood discharge capacity and collapse prevention of earth-rock dams. It is urgent to find an economical, environmentally friendly, and durable sand solidification technology. However, the traditional grouting reinforcement method has some problems, such as high costs, complex operations, and environmental pollution. Enzyme-induced calcium carbonate precipitation (EICP) is an anti-seepage reinforcement technology emerging in recent years with the characteristics of economy, environmental protection, and durability. The erosion resistance and shear strength of earth-rock dams solidified by EICP need further verification. In this paper, EICP-solidified standard sand is taken as the research object, and EICP-cemented standard sand is carried out by a consolidated undrained triaxial test. A two-stage pouring method is adopted to pour samples, and the effects of dry density, cementation times, standing time, and confining pressure on the shear strength of cemented standard sand are emphatically analyzed. The relationship between cohesion, internal friction angle, and CaCO3 formation was analyzed. After the optimal curing conditions are obtained through the triaxial shear strength test, the erosion resistance model test is carried out. The effects of erosion angle, erosion flow rate, and erosion time on the erosion resistance of EICP-solidified sand were analyzed through an erosion model test. The results of triaxial tests show that the standard sand solidified by EICP exhibits strain softening, and the peak strength increases with the increase in initial dry density, cementation times, standing time, and confining pressure. When the content of CaCO3 increases from 2.84 g to 12.61 g, the cohesive force and internal friction angle change to 23.13 times and 1.18 times, and the determination coefficients reach 0.93 and 0.94, respectively. Erosion model test results indicate that the EICP-solidified sand dam has good erosion resistance. As the increase in erosion angle, erosion flow rate, and erosion time, the breach of solidified samples gradually becomes larger. Due to the deep solidification of sand by EICP, the development of breaches is relatively slow. Under different erosion conditions, the solidified samples did not collapse and the dam broke. The research results have important reference value and scientific significance for the practice of sand consolidation engineering in earth-rock dams.

Sharp decline in surface water resources for agriculture and fisheries in the Lower Mekong Basin over 2000-2020.

Water resources play a crucial role in the global water cycle and are affected by human activities and climate change. However, the impacts of hydropower infrastructures on the surface water extent and volume cycle are not well known. We used a multi-satellite approach to quantify the surface water storage variations over the 2000-2020 period and relate these variations to climate-induced and anthropogenic factors over the whole basin. Our results highlight that dam operations have strongly modified the water regime of the Mekong River, exhibiting a 55 % decrease in the seasonal cycle amplitude of inundation extent (from 3178 km2 to 1414 km2) and a 70 % decrease in surface water volume (from 1109 km3 to 327 km3) over 2000-2020. In the floodplains of the Lower Mekong Basin, where rice is cultivated, there has been a decline in water residence time by 30 to 50 days. The recent commissioning of big dams (2010 and 2014) has allowed us to choose 2015 as a turning point year. Results show a trend inversion in rice production, from a rise of 40 % between 2000 and 2014 to a decline of 10 % between 2015 and 2020, and a strong reduction in aquaculture growth, from +730 % between 2000 and 2014, to +53 % between 2015 and 2020. All these results show the negative impact of dams on the Mekong basin, causing a 70 % decline in surface water volumes, with major repercussions for agriculture and fisheries over the period 2000-2020. Therefore, new future projects such as the Funan Techo canal in Cambodia, scheduled to start construction at the end of 2024, will particularly affect 1300 km2 of floodplains in the lower Mekong basin, with a reduction in the amount of water received, and other areas will be subjected to flooding. The human, material and economic damage could be catastrophic.

Excluding livestock access to farm dams reduces methane emissions and boosts water quality.

Farm dams, also known as 'agricultural ponds', are ubiquitous features of agricultural landscapes globally. Those accessed by livestock have high methane (CH4) emissions per unit area relative to other freshwater systems. Fencing dams and installing water troughs to prevent livestock from entering the dams are promising strategies to improve water quality and substantially reduce their carbon footprints. However, previous studies only measured the effects of fencing on methane diffusive emissions without considering ebullitive fluxes (i.e., methane bubbles), which is often the dominant emission pathway in smaller water bodies. Also, data is lacking on how the benefits of fencing farm dams vary across seasons. Using Australia as a test case, this study investigates the benefit of fencing off farm dams by monitoring total CH4 (diffusion + ebullition) and carbon dioxide (CO2) in summer and winter. Fenced dams had 72 % lower CH4 emissions in summer and 92 % lower in winter than unfenced dams. Similarly, CO2-equivalent (CO2 + CH4) fluxes were lower in fenced dams by 59 % in summer and 73 % in winter. Fenced dams had higher water quality, with 51 % less total dissolved nitrogen, 57 % less phosphorous, and 23-49 % more dissolved oxygen. Average daily air temperature was a key predictor of CH4 emissions from farm dams, underscoring the importance of considering temporal dynamics for estimating yearly farm dam emissions. We confirmed that excluding livestock from entering farm dams using fences significantly mitigates CH4 emissions and enhances water quality, and these benefits are maintained seasonally.

A Comparative Investigation of Aerosol Generation and Exposure Risk During Access Cavity Preparation With or Without Rubber Dam Application.

BACKGROUND: Aerosols generated during dental procedures have taken the forefront of discussion in dentistry. Due to the nature of their work, dental professionals face a significant risk of exposure to various biological hazards, such as saliva, blood, aerosols, and droplets. Aerosols, which are tiny particles with a diameter of less than 50µm, have a unique property that allows them to stay suspended in the air for extended periods. This is primarily due to their small size and lightweight nature which makes them highly susceptible to air currents and prevents them from quickly settling down. As a result, these aerosols can linger in the atmosphere, creating a potential risk for respiratory infections. AIM: The aim is to evaluate and compare the efficacy of rubber dams in preventing aerosols generated cross-contamination. METHODS AND MATERIAL: This in-vivo experimental study comprised 60 individuals who were suggested for root canal treatment in the mandibular first permanent molar tooth. The passive air sampling technique using "settle plates" was applied to investigate microbial fallout during access opening with and without rubber dam application. Sheep blood agar plates were used to do the colony forming unit (CFU) count. All patients were randomly divided into two groups comprising 30 patients each based on usage of rubber dam application or not, i.e., Group I: Without rubber dam application and Group II: With rubber dam application. RESULTS: Using a rubber dam while performing an endodontic procedure significantly impacts decreased aerosol generation at 0.5-m and 2-m distances than its counterpart with a p-value < 0.01. CONCLUSION: Using a rubber dam during endodontic procedures reduces the likelihood of aerosol generation, thereby decreasing the risk of cross-contamination and lowering the susceptibility of dental professionals to respiratory illnesses.

Effect of seasonal variations in sea level on residual saltwater removal upstream of subsurface dam in coastal layered heterogeneity aquifers.

Subsurface dams have been recognized as one of the most effective measures for preventing saltwater intrusion. However, it may result in large amounts of residual saltwater being trapped upstream of the dam and take years to decades to remove, which may limit the utilization of fresh groundwater in coastal areas. In this study, field-scale numerical simulations were used to investigate the mechanisms of residual saltwater removal from a typical stratified aquifer, where an intermediate low-permeability layer (LPL) exists between two high-permeability layers, under the effect of seasonal sea level fluctuations. The study quantifies and compares the time of residual saltwater removal (Tre) for constant sea level (CSL) and seasonally varying sea level (FSL) scenarios. The modelling results indicate that, in most cases, seasonal fluctuations in sea level facilitate the dilution of residual saltwater and thus accelerate residual saltwater removal compared to a static sea level scenario. However, accounting for seasonal sea level variations may increase the required critical dam height (the minimum dam height required to achieve complete residual saltwater removal). Sensitivity analyses show that Tre decreases with increasing height of subsurface dam (Hd) under CSL or weaker sea level fluctuation scenarios; however, when the magnitude of sea level fluctuation is large, Tre changes non-monotonically with Hd. Tre decreases with increasing distance between subsurface dam and ocean for both CSL and FSL scenarios. We also found that stratification model had a significant effect on Tre. The increase in LPL thickness for both CSL and FSL scenarios leads to a decrease in Tre and critical dam height. Tre generally shows a non-monotonically decreasing trend as LPL elevation increases. These quantitative analyses provide valuable insights into the design of subsurface dams in complex situations.

A preliminary study on the feasibility of two different cow-calf contact systems in a pasture-based, seasonal calving dairy system: effects on cow production and health.

Internationally, consumer dissatisfaction with cow-calf separation at birth has led to increased interest in alternative calf-rearing methods, specifically cow-calf contact (CCC) systems. The objectives of this preliminary study were to estimate whether CCC could be incorporated into an Irish spring-calving, pasture-based system, and to investigate the effects on cow milk production and health. Three systems were compared: the conventional Irish system (CONV;18 cows), cow and calf were separated < 1 h postbirth, cows were pasture-based and milked twice-a-day; a full-time access system (FT;14 cows), cow and calf were allowed constant, unrestricted access, were pasture-based, and cows were milked twice-a-day; and a part-time access system (PT;18 cows), cow and calf had unrestricted access when indoors at night, cows grazed outdoors by day while calves remained indoors, and cows were milked once-a-day in the morning. Cows were blocked and balanced across the three systems by previous lactation machine milk yield (MMY), BW, and body condition score (BCS). Following an 8-week CCC period, all calves were weaned (FT and PT underwent a 7-d gradual weaning and separation process) and all cows were milked twice-a-day. Cow MMY was recorded daily and milk composition was recorded weekly; milk data were analysed from weeks 1 to 8 (CCC period), weeks 9 to 35 (post-CCC period), and weeks 1 to 35 (cumulative lactation). Cow BW and BCS were taken weekly for weeks 1-12, and at the end of the lactation. During the CCC period, all systems differed (P < 0.001) in MMY (mean ± SEM; 24.0, 13.6, and 10.3 ± 0.50 kg/d for CONV, FT, and PT cows, respectively). After the CCC period, CONV MMY (20.2 ± 0.48 kg/d) remained higher (P < 0.001) than the FT (16.6 kg/d) and PT cows (15.7 kg/d). The FT and PT cows yielded 24 and 31% less in cumulative lactation MMY and 26 and 35% less in cumulative lactation milk solids yield, respectively, compared to CONV (5 072 ± 97.0 kg and 450 ± 8.7 kg). During the CCC period, somatic cell score was higher (P = 0.030) in PT cows (5.15 ± 0.118) compared to FT cows (4.70 ± 0.118), while CONV (4.94 ± 0.118) were inconclusive to both. The PT cows (523 ± 4.9 and 520 ± 6.8 kg) were heavier than the CONV (474 ± 4.9 and 479 ± 6.8 kg) and FT (488 ± 4.9 and 487 ± 6.8 kg) cows at week 4 and week 8 (both P < 0.001). The PT cows had higher BCS than CONV and FT at all observed times. This preliminary research suggests that although CCC was incorporated without impacting cow health, the two CCC systems investigated negatively affected cow production.

Pace of heavy metal pollution in the anthropogenically altered and industrialized Nakdong River Estuary, South Korea: Implications for the Anthropocene.

Estuaries, vital coastal ecosystems, face growing threats from industrialization. To understand the pace of sedimentary changes and heavy metal pollution at the anthropogenically altered and industrialized Nakdong River Estuary in South Korea, we used sediment coring to reconstruct environmental change. Estuarine dam construction in 1934 shifted the sedimentary system from sand to mud, coinciding with a post-1930s mercury increase due to coal burning. Mercury concentrations in other South Korean regions surged in the 1970s, indicating proximity to emission sources matters. However, most heavy metal levels (Cu, Cd, Zn, Ag) sharply rose in the 1960s and 1970s with regional industrialization. Modern heavy metal concentrations doubled pre-industrial levels, underscoring human activities as the primary driver of Nakdong Estuary environmental changes. This emphasizes the need for a balanced approach to development and environmental preservation.

Functional evidence on the involvement of the MADS-box gene MdDAM4 in bud dormancy regulation in apple.

Over the course of the year, temperate trees experience extremes in temperature and day length. In order to protect themselves from frost damage in winter, they enter a dormant state with no visible growth where all leaves are shed and buds are dormant. Also the young floral tissues need to withstand harsh winter conditions, as temperature fruit trees like apple develop their flower buds in the previous year of fruit development. So far, the genetic control of induction and release of dormancy is not fully understood. However, the transcription factor family of DORMANCY-Associated MADS-box (DAM) genes plays a major role in the control of winter dormancy. One of these genes is MdDAM4. This gene is expressed in the early phase of bud dormancy, but little is known about its function. Six transgenic apple lines were produced to study the function of MdDAM4 in apple. For plant transformation, the binary plasmid vector p9oN-35s-MdDAM4 was used that contains the coding sequence of MdDAM4 driven by the 35S promoter. Transgenicity of the lines was proven by PCR and southern hybridization. Based on siRNA sequencing and phenotypic observations, it was concluded that line M2024 overexpresses MdDAM4 whereas the gene is silenced in all other lines. Phenotyping of the transgenic lines provided evidence that the overexpression of MdDAM4 leads to an earlier induction and a later release of dormancy. Silencing this gene had exactly the opposite effects and thereby led to an increased duration of the vegetation period. Expression experiments revealed genes that were either potentially repressed or activated by MdDAM4. Among the potentially suppressed genes were several homologs of the cytokinin oxidase 5 (CKX5), five LOX homologs, and several expansins, which may indicate a link between MdDAM4 and the control of leaf senescence. Among the potentially activated genes is MdDAM1, which is in line with observed expression patterns during winter dormancy. MdDAM2, which shows little expression during endodormancy also appears to be activated by MdDAM4. Overall, this study provides experimental evidence with transgenic apple trees for MdDAM4 being an important regulator of the onset of bud dormancy in apple.

Effect of parasitic infection on microplastic ingestion in a native leuciscid hybrid species (Alburnus derjugini x Squalius orientalis) from Kürtün Dam Lake, Türkiye.

Microplastic (MP) pollution is currently one of the most serious environmental issues. MPs were investigated in the Kürtün Dam Lake in healthy individuals of the native leuciscid hybrid (Alburnus derjugini x Squalius orientalis) species and individuals infected with the Ligula intestinalis parasite. Although MP abundance appeared to be higher in non-infected fish (NIF) than in L. intestinalis (L) and infected fish (IF), the MP abundance in IF was higher, because the parasite theoretically belongs to IF. In addition to the observation of MPs in the gastrointestinal tract (GIT) of fish, the diffusion of MPs by parasites settled in the body cavity indicates that MPs are not only present in the GIT. Therefore, predation on existing fish by birds causes MP dispersion. In the present study, the most common MP shape was fiber (100% for NIF and IF, 85.7% for L), the MP color was black (57.1% for IF and L) and orange (50% for NIF), and the polymer type was polyamide (57.1% for IF, 50% for NIF) and polyethylene terephthalate (28.5% for L). These MP compositions led us to believe that textile effluents and aquaculture operations in dam lakes could be sources of pollution. Therefore, this study provides insights for future research to elucidate the connection between MP consumption and parasite infection.

The main threats facing the eel (Anguilla anguilla) and the sea lamprey (Petromyzon marinus) in Galicia (NW Spain) through Partial Least Squares Path Modelling.

Migratory fish are very important species from an ecological and socioeconomic point of view, but they suffer the effects of many threats such as climate change, pollution, or overfishing, thus contributing to the decline of these species. To study the main factors influencing these species, Partial Least Squares Path Modelling (PLS-PM) methodology has been used to analyse and quantify the main threats facing two highly relevant migratory species: the eel (Anguilla anguilla) and the sea lamprey (Petromyzon marinus). Based on this statistical approach, two models have been developed for a total of 14 rivers located in the Autonomous Community of Galicia (NW Spain), one for the eel and the other for the lamprey. For the construction of the models, the influence of environmental factors, surface water quality and anthropogenic impacts on the population of these species has been studied. Two scenarios have also been simulated to assess how the application of corrective measures to reduce the anthropogenic impact implies important improvements to the eel and lamprey populations. The results of the models developed indicate that the variables analysed predict 69% of the eel "Population", with the weight of the measured variables (MV) 'Water treatment plants' having the most substantial weight (W=0.939) followed by the significant negative influence of 'Surface area of reservoirs and rivers' (W=-0.746). Similarly, in the lamprey model, an R2 of 0.58 has been obtained, where the negative influence of the MV "Agricultural nitrate discharge points" (-0.938) stands out substantially. In relation to the scenarios developed for both species, we highlight that the application of measures aimed at reducing anthropogenic pressure manages to mitigate the impact by 4.82% in the case of eel and by 1.37% in the case of lamprey. The set of models and scenarios proposed will make it possible to design preventive and corrective measures to mitigate the impacts affecting these populations, guaranteeing the integrated management of these species, and improving future decision-making, thus strengthening environmental governance.

Viral Envelope Evolution in Simian-HIV-Infected Neonate and Adult-Dam Pairs of Rhesus Macaques.

We recently demonstrated that Simian-HIV (SHIV)-infected neonate rhesus macaques (RMs) generated heterologous HIV-1 neutralizing antibodies (NAbs) with broadly-NAb (bNAb) characteristics at a higher frequency compared with their corresponding dam. Here, we characterized genetic diversity in Env sequences from four neonate or adult/dam RM pairs: in two pairs, neonate and dam RMs made heterologous HIV-1 NAbs; in one pair, neither the neonate nor the dam made heterologous HIV-1 NAbs; and in another pair, only the neonate made heterologous HIV-1 NAbs. Phylogenetic and sequence diversity analyses of longitudinal Envs revealed that a higher genetic diversity, within the host and away from the infecting SHIV strain, was correlated with heterologous HIV-1 NAb development. We identified 22 Env variable sites, of which 9 were associated with heterologous HIV-1 NAb development; 3/9 sites had mutations previously linked to HIV-1 Env bNAb development. These data suggested that viral diversity drives heterologous HIV-1 NAb development, and the faster accumulation of viral diversity in neonate RMs may be a potential mechanism underlying bNAb induction in pediatric populations. Moreover, these data may inform candidate Env immunogens to guide precursor B cells to bNAb status via vaccination by the Env-based selection of bNAb lineage members with the appropriate mutations associated with neutralization breadth.

Human-made small reservoirs alter dryland hydrological connectivity.

Our research shed light on the distribution, number, and impact of small reservoirs (SRs) on rural dryland water availability and hydrology. We measured the storage capacity, relationship to environmental variables, and effects on the hydrology of all SRs (1225) found within a Sonoran Desert basin. SRs were predominantly associated with Tertiary conglomerates and Quaternary alluvium and were less common in extrusive rocks. A higher concentration of reservoirs was observed in woodlands and thornscrub, with fewer SRs in desertscrub than anticipated by chance. The average size of these small reservoirs was 5205 m2. All SRs reached full storage capacity during the rainy season, but only 20 % retained water throughout the year. Furthermore, our analysis revealed a significant impact on basin connectivity, with only 41 % of superficial drainage being connected. Notably, two large dams were found to disconnect 26 % of the basin. Despite their relatively small watershed footprint, SRs were found to be responsible for disconnecting 33 % of the total basin area. The magnitude of rainfall events played a crucial role in connectivity dynamics. Low-magnitude rainfall events led to sediment retention in SRs, reducing connectivity, while moderate events increased connectivity by repeatedly filling SRs. High-magnitude events reshaped channels, transported sediments, and enhanced overall connectivity. The concentration of SRs in the upper reaches of the basin coincides with higher stocking rates. SRs, are relatively recent additions to desert landscapes, impacting ecological dynamics. Their construction and use fragment an already disjointed basin, thereby restricting water retention by larger dams. These findings emphasize the intricate relationship between SRs, rainfall occurrences, and the overall connectivity of the basin. We underline that documenting the cumulative effects of SRs yields valuable insights for managing water resources in arid ecosystems.

Body length determines flow refuging for rainbow trout (Oncorhynchus mykiss) behind wing dams.

Complex hydrodynamics abound in natural streams, yet the selective pressures these impose upon different size classes of fish are not well understood. Attached vortices are produced by relatively large objects that block freestream flow, which fish routinely utilize for flow refuging. To test how flow refuging and the potential harvesting of energy (as seen in Kármán gaiting) vary across size classes in rainbow trout (Oncorhynchus mykiss; fingerling, 8 cm; parr, 14 cm; adult, 22 cm; n=4 per size class), we used a water flume (4100 l; freestream flow at 65 cm s-1) and created vortices using 45 deg wing dams of varying size (small, 15 cm; medium, 31 cm; large, 48 cm). We monitored microhabitat selection and swimming kinematics of individual trout and measured the flow field in the wake of wing dams using time-resolved particle image velocimetry (PIV). Trout of each size class preferentially swam in vortices rather than the freestream, but the capacity to flow refuge varied according to the ratio of vortex width to fish length (WV:LF). Consistent refuging behavior was exhibited when WV:LF≥1.5. All size classes exhibited increased wavelength and Strouhal number and decreased tailbeat frequency within vortices compared with freestream, suggesting that swimming in vortices requires less power output. In 17% of the trials, fish preferentially swam in a manner that suggests energy harvesting from the shear layer. Our results can inform efforts toward riparian restoration and fishway design to improve salmonid conservation.

A comparative study of remotely sensed reservoir monitoring across multiple land cover types.

Continuous monitoring of reservoirs and dams is essential for efficient water management. Synthetic Aperture Radar (SAR) imagery offers the potential for continuous monitoring of surface water through all-weather ground observation. The objective of this study is to enhance the accuracy of water body detection and water quantity estimation by applying 64 combinations of speckle filtering and object detection techniques to Sentinel-1 imagery. For speckle filtering, the Median, Gaussian, Lee, and Frost techniques were used with various window sizes (3, 5, 7, and 9). For water body detection, the Otsu, Kittler-Illingworth (KI), Chan-Vese (CV), and K-means methods were employed. The study area included three reservoirs and two dams in Korea, encompassing a variety of water surface sizes and types of land cover. To validate the accuracy of each water body detection combination, manual delineation-based water mask images from Sentinel-2 were employed. Furthermore, a regression equation (y=axb) between water surface area and storage was used to estimate water storage based on SAR imagery, followed by time-series validation using in-situ data. The research results indicate that the optimal detection technique varies significantly depending on the type of surrounding land cover and the size of the water body. The highest performance was observed for the CV technique combination for waterfront pixels, and for the KI technique combination for other land cover pixels. In speckle filtering techniques using a large window size, the false detection rate caused by vegetation and buildings was low; however, the boundaries of water bodies were blurred. Consequently, using smaller window sizes in SAR imagery and leveraging optimal water body detection combinations specific to land cover types, along with post-processing using masking data, would enhance the performance of water surface area and storage estimation.

Assessment of heavy metal levels in polyculture fish farms and their aquatic ecosystems: an integrative study addressing environmental and human health risks associated with dam water usage.

This study examines the levels of heavy metals in polyculture fish (Labeo rohita, Cyprinus carpio, and Catla catla), water, and sediment in Tanda Dam, Kohat, Pakistan, aiming to understand environmental and health risks. Samples of fish, water, and sediment were collected from 3 fish farms, and heavy metal concentrations were measured using a Flame Atomic Absorption Spectrophotometer (AAS). Results reveal that C. catla exhibited significantly higher (p < 0.05) levels of Zn than other fish species. Conversely, C. carpio showed significantly higher (p < 0.05) concentrations of Pb, Cd, Cr, Mn, Cu, As, and Ni than other species. The heavy metal hierarchy in C. carpio was found to be Zn > Cu > Pb > Cr > Cd > Mn > As > Ni. While heavy metal levels in L. rohita and C. catla generally fell within reference ranges, exceptions were noted for Zn, Pb, and Cd. Conversely, in C. carpio, all metals exceeded reference ranges except for Cu and Ni. Principal Component Analysis (PCA) indicated a close relationship between water and sediment. Additionally, cluster analysis suggested that C. catla formed a distinct cluster from L. rohita and C. carpio, implying different responses to the environment. Despite concerns raised by the Geoaccumulation Index (Igeo) and Contamination Factor (CF), particularly for Cd, which exhibited a high CF. Furthermore, Hazard Index (HI) values for all three fish species were below 1, suggesting low health risks. However, elevated Igeo and CF values for Cd suggest significant pollution originating from anthropogenic sources. This study underscores the importance of monitoring heavy metals in water for both environmental preservation and human health protection. Future research efforts should prioritize pollution control measures to ensure ecosystem and public health safety.

A method to describe attenuation of river contamination under peak flows: Can the public water supply from Paraopeba River finally return after the Brumadinho dam disaster?

Tailings dams' disasters begin a stage of river water contamination with no endpoint at first sight. But when the river was formerly used for public water supply and the use was suspended as consequence of a dam break, a time window for safe suspension lift must be anticipated to help water managers. The purpose of this study was to seek for that moment in the case of Brumadinho dam disaster which occurred in 2019 and injected millions of cubic meters of iron- and manganese-rich tailings into the Paraopeba River, leading to the suspension of public water supply to Belo Horizonte metropolitan region with this resource, until now. To accomplish the proposed goal, an assemblage of artificial intelligence and socio-economic development models were used to anticipate precipitation, river discharge and metal concentrations (iron, manganese) until 2033. Then, the ratios of metal concentrations between impacted and non-impacted sites were determined and values representing extreme events of river discharge were selected for further assessment. A ratio ≈1 generally indicates a similarity between impacted and non-impacted areas or, put another way, a return of impacted areas to a pre-rupture condition. Moreover, when the ratio is estimated under the influence of peak flows, then a value of ≈1 indicates a return to pre-rupture conditions under the most unfavorable hydrologic regimes, thus a safe return. So, the extreme ratios were plotted against time and fitted to a straight line with intercept-x representing the requested safe time. The results pointed to 6.57 years after the accident, while using iron as contaminant indicator, or 8.71 years when manganese was considered. Despite of being a relatively low-risk timeframe, the suspension lift should be implemented in phases and monitored for precaution of potential sporadic contamination events, while dredging of the tailings from impacted areas should continue and be accelerated.