Efficiency Of Screens Research Articles

Separation efficiency of a wastewater bar screen based on a 3D computational fluid dynamics modeling

The wastewater screening process is a crucial step in the majority of wastewater treatment plants, frequently using mechanical bar screens as the first filtration step to remove heavy debris from the wastewater flow. In the present study, two 3D geometries of bar screens with different screen openings were presented to investigate the effect of the variation in screen spacing of bars on the separation efficiency of debris. Based on the Ansys Fluent CFD code within the Eulerian-Lagrangian approach, the particle trajectories were tracked, and the retention efficiency of these two bar screens was evaluated. The results show that a higher particle separation efficiency is favored for small bar spacing and coarse particle sizes. Actually, despite the impact of bar spacing on the separation efficiency of particles, the adequate choice of this parameter is related to particle properties and the fluid flow inlet velocity. These parameters also have a great influence on the separation efficiency of bar screens. The study can help for more structural improvements in the shape of the screening media, which leads to enhanced performance of wastewater screening facilities.

Forward genetic screen of the C. elegans million mutation library reveals essential, cell-autonomous contributions of BBSome proteins to dopamine signaling.

The nematode Caenorhabditis elegans is well known for its ability to support forward genetic screens to identify molecules involved in neuronal viability and signaling. The proteins involved in C. elegans dopamine (DA) regulation are highly conserved across evolution, with prior work demonstrating that the model can serve as an efficient platform to identify novel genes involved in disease-associated processes. To identify novel players in DA signaling, we took advantage of a recently developed library of pre-sequenced mutant nematodes arising from the million mutation project (MMP) to identify strains that display the DA-dependent swimming-induced-paralysis phenotype (Swip). Our screen identified novel mutations in the dopamine transporter encoding gene dat-1, whose loss was previously used to identify the Swip phenotype, as well as multiple genes with previously unknown connections to DA signaling. Here, we present our isolation and characterization of one of these genes, bbs-1, previously linked to the function of primary cilia in worms and higher organisms, including humans, and where loss-of-function mutations result in a human disorder known as Bardet-Biedl syndrome. Our studies of C. elegans BBS-1 protein, as well as other proteins that are known to be assembled into a higher order complex (the BBSome) reveal that functional or structural disruption of this complex leads to exaggerated C. elegans DA signaling to produce Swip via a cell-autonomous mechanism. We provide evidence that not only does the proper function of cilia in C. elegans DA neurons support normal swimming behavior, but also that bbs-1 maintains normal levels of DAT-1 trafficking or function via a RHO-1 and SWIP-13/MAPK-15 dependent pathway where mutants may contribute to Swip independent of altered ciliary function. Together, these studies demonstrate novel contributors to DA neuron function in the worm and demonstrate the utility and efficiency of forward genetic screens using the MMP library.

Predicting Screening Efficiency of Probability Screens Using KPCA‐GRNN with WP‐EE Feature Reconstruction

The screening system is a nonlinear and non‐Gaussian complex system. To better characterize its attributes and improve the prediction accuracy of screening efficiency, this study involves the acquisition of the vibration signals and screening efficiency data under various operational conditions. Subsequently, empirical mode decomposition energy entropy (EMD‐EE), variational mode decomposition energy entropy (VMD‐EE), and wavelet packet energy entropy (WP‐EE) features are extracted from the time series vibration signals, and three single input energy entropy‐generalized regressive neural network (GRNN) prediction accuracy models are established and compared. Furthermore, we introduce the kernel principal component analysis (KPCA)‐WP‐EE feature reconstruction‐GRNN prediction algorithm. This approach involves reconstructing the feature vector by optimizing WP‐EE‐GRNN prediction under varying parameters. The parameterized GRNN model is then predicted and analyzed through secondary reconstruction involving KPCA dimensionality reduction features. The results show that WP‐EE‐GRNN achieves superior prediction accuracy compared to box dimension (d)‐GRNN, box dimension‐back propagation neural network (BPNN), and d‐weighted least squares support vector machine, WP‐d‐GRNN, WP‐EE‐BPNN, EMD‐EE‐GRNN, and VMD‐EE‐GRNN. Additionally, the WP‐EE feature reconstruction‐GRNN algorithm exhibits higher prediction accuracy than the single‐input WP‐EE‐GRNN algorithm. The WP‐EE‐GRNN prediction algorithm using KPCA dimensionality reduction and secondary reconstruction not only achieves higher prediction accuracy than prior to KPCA dimensionality reduction but also improves prediction efficiency. Following the extraction of two core principal components, model parameters when KPCA’s σ2 = 0.85, the optimal parameter of GRNN model Spread = 0.051, and the optimal number of training samples N = 19, the average prediction error is 1.434%, the minimum prediction error reaching 0.708%, the minimum root mean square error reaching 0.836% and Pearson correlation coefficient marking the closest to 1, these result all representing the optimum achievable values. The budget model selects the optimal parameter combination scheme for the system.

Airborne-Spray-Drift Collection Efficiency of Nylon Screens: Measurement and CFD Analysis

Pesticide application is essential for improving crop productivity; however, undesirable pesticide drift must be mitigated because of its adverse impacts on humans, the environment and ecosystems. The collection and accurate quantification of airborne droplets are key elements involved in identifying the spatial and temporal dispersion of off-target spray movement. Various types of passive and active collectors have been deployed to measure airborne spray drift; however, the collection efficiencies of only a few samplers have been verified. This study evaluated the collection efficiency of two airborne-spray-drift collectors using an experimental drift wind tunnel. The airborne spray drifts were quantified by a total organic carbon analyser and validated by comparison to measurements using liquid chromatography with tandem mass spectrometry. Computational fluid dynamics (CFD) simulations were used to explore the effects of droplet size and wind speed on the collection performance. It was found that nylon screens, passive samplers, captured 57.9–88.1% of the airborne spray drift. These results are considered reliable and are comparable to those found in the literature. Additionally, the CFD results demonstrated that the collection efficiency increased with droplet diameter. An increase in wind speed improved the collection efficiency of fine droplets (≤100 μm diameter); however, wind speed had no significant influence on the collection of coarse droplets. These measurements, alongside the aerodynamic approach adopted in this study, can provide a comprehensive understanding of the collection performance of nylon screens.

Experimental Evaluation of the Multiphase Flow Effect on Sand Production Process: Prepack Sand Retention Testing Results

This paper considers a field with high-viscosity oil in a terrigenous weakly consolidated reservoir (sandstone) with a massive gas cap and an aquifer. The major challenge in the field operation is the migration of solid sand particles into the well, accompanied by a breakthrough of water and/or gas. The goal of the investigation was to evaluate the degree of influence on the sanding process of water and gas shares in the produced fluid and to determine the effect of pressure drop. The research methodology is based on a series of filtration experiments on small-sized bulk reservoir models. Particle size distribution of bulk models was created in accordance with that of the reservoir. The experiments were made in the form of Prepack Sand Retention Tests (SRT). Gas breakthrough allows sand production on a relatively high level for a longer amount of time, even though the concentration of solids in the produced fluid is lower than that of water breakthrough. On the other hand, water breakthrough triggers higher sand production, but it rapidly decreases as time goes on. Retained permeability of the model-screen system from the drawdown pressure (pressure gradient) and phase distribution of the flow were investigated. Moreover, a methodology has been developed for conducting filtration tests on bulk reservoir models to evaluate the efficiency of different screens (wire-wrapped screens, in particular).

A Critical Review of Zebrafish Models of Parkinson's Disease.

A wide variety of human diseases have been modelled in zebrafish, including various types of cancer, cardiovascular diseases and neurodegenerative diseases like Alzheimer’s and Parkinson’s. Recent reviews have summarized the currently available zebrafish models of Parkinson’s Disease, which include gene-based, chemically induced and chemogenetic ablation models. The present review updates the literature, critically evaluates each of the available models of Parkinson’s Disease in zebrafish and compares them with similar models in invertebrates and mammals to determine their advantages and disadvantages. We examine gene-based models, including ones linked to Early-Onset Parkinson’s Disease: PARKIN, PINK1, DJ-1, and SNCA; but we also examine LRRK2, which is linked to Late-Onset Parkinson’s Disease. We evaluate chemically induced models like MPTP, 6-OHDA, rotenone and paraquat, as well as chemogenetic ablation models like metronidazole-nitroreductase. The article also reviews the unique advantages of zebrafish, including the abundance of behavioural assays available to researchers and the efficiency of high-throughput screens. This offers a rare opportunity for assessing the potential therapeutic efficacy of pharmacological interventions. Zebrafish also are very amenable to genetic manipulation using a wide variety of techniques, which can be combined with an array of advanced microscopic imaging methods to enable in vivo visualization of cells and tissue. Taken together, these factors place zebrafish on the forefront of research as a versatile model for investigating disease states. The end goal of this review is to determine the benefits of using zebrafish in comparison to utilising other animals and to consider the limitations of zebrafish for investigating human disease.

Rapid Inhibitor Discovery by Exploiting Synthetic Lethality.

Synthetic lethality occurs when inactivation of two genes is lethal but inactivation of either single gene is not. This phenomenon provides an opportunity for efficient compound discovery. Using differential growth screens, one can identify biologically active compounds that selectively inhibit proteins within the synthetic lethal network of any inactivated gene. Here, based purely on synthetic lethalities, we identified two compounds as the only possible inhibitors of Staphylococcus aureus lipoteichoic acid (LTA) biosynthesis from a screen of ∼230,000 compounds. Both compounds proved to inhibit the glycosyltransferase UgtP, which assembles the LTA glycolipid anchor. UgtP is required for β-lactam resistance in methicillin-resistant S. aureus (MRSA), and the inhibitors restored sensitivity to oxacillin in a highly resistant S. aureus strain. As no other compounds were pursued as possible LTA glycolipid assembly inhibitors, this work demonstrates the extraordinary efficiency of screens that exploit synthetic lethality to discover compounds that target specified pathways. The general approach should be applicable not only to other bacteria but also to eukaryotic cells.

High-throughput design of bacterial anti-sense RNAs using CAREng.

Short RNA (sRNA) modulation of gene expression is an increasingly popular tool for bacterial functional genomics. Antisense pairing between an sRNA and a target messenger RNA results in post-transcriptional down-regulation of a specific gene and can thus be used both for investigating individual gene function and for large-scale genetic screens. sRNAs have several advantages over knockout libraries in studies of gene function, including inducibility, the capacity to interrogate essential genes and easy portability to multiple genetic backgrounds. High-throughput, systematic design of antisense RNAs will increase the efficiency and repeatability of sRNA screens. To this end, we present CAREng, the Computer-Automated sRNA Engineer. CAREng designs antisense RNAs for all coding sequences in a given genome, while checking for potential off-targets. CAREng is available as a Python script and through a web portal (https://caren.carleton.ca). Supplementary data are available at Bioinformatics Advances online.

Evaluating the Efficiency of Off-Ball Screens in Elite Basketball Teams via Second-Order Markov Modelling

In basketball, the offensive movements on both strong and weak sides and tactical behavior play major roles in the effectiveness of a team’s offense. In the literature, studies are mostly focused on offensive actions, such as ball screens on the strong side. In the present paper, for the first time a second-order Markov model is defined to evaluate players’ interactions on the weak side, particularly for exploring the effectiveness of tactical structures and off-ball screens regarding the final outcome. The sample consisted of 1170 possessions of the FIBA Basketball Champions League 2018–2019. The variables of interest were the type of screen on the weak side, the finishing move, and the outcome of the shot. The model incorporates partial non-homogeneity according to the time of the execution (0–24″) and the quarter of playtime, and it is conditioned on the off-ball screen type. Regarding the overall performance, the results indicated that the outcome of each possession was influenced not only by the type of the executed shot, but also by the specific type of screen that took place earlier on the weak side of the offense. Thus, the proposed model could operate as an advisory tool for the coach’s strategic plans.

АНАЛІЗ ЕФЕКТИВНОСТІ ПЕРЕДАЧІ ЕЛЕКТРИЧНОЇ ЕНЕРГІЇ В СИСТЕМІ БЕЗДРОТОВОЇ ЗАРЯДКИ АКУМУЛЯТОРНОЇ БАТАРЕЇ ЕЛЕКТРОМОБІЛЯ

Theoretical researches of efficiency of electric energy transfer in the wireless charger of inductive type with serial resonance in circles of transmitting and receiving coils are carried out. It is shown that this efficiency depends on the parameter (the product of the magnetic coupling coefficient and the Q- factor of the coils) and the ratio of the active resistances of the battery and the coil. It is shown that there is an optimal value of this ratio, at which the efficiency of the device is maximum (when ) and its value increases monotonically with increasing parameter . Moreover, to achieve an efficiency greater than 0.8, it is necessary to have a system of coils with a value of 10. The graphical dependences that determine the value of this efficiency as a function of these two parameters and set the allowable interval for changing the resistance ratio in terms of high energy efficiency. Numerical calculation of the high-frequency magnetic field (with an operating frequency of 100 kHz) generated by the coils was performed, in two cases - in the absence of shielding and in the presence of aluminum electromagnetic screens and showed high efficiency of such screens. The peculiarity of the calculation is that to determine the values of complex currents in both coils, which depend on the mode of operation of the whole device, use their preliminary calculation based on the created Simulink-model of the device. References 14, figures 5, table 2.

Study of working conditions in aluminum casting shops worksites

The results of the study of working conditions in aluminum casting shops worksites are presented. The results of these studies showed that in worksites there are exceedance of the permissible limits for noise, vibration, the content of harmful substances in the working environment, intensity of infrared (thermal) radiation and air temperature. There is effect of electromagnetic radiation on the workers during the service of induction furnaces. In addition, the main harmful production factors include the severity of work and the intensity of the labor process. The efficiency of the protective screens of the IAT-6 induction crucible furnace was evaluated.

ДО ОБҐРУНТУВАННЯ ЗАСТОСУВАННЯ ШУМОЗАХИСНИХ ЕКРАНІВ ІЗ ВИСОКИМИ ШУМОПОГЛИНАЮЧИМИ ВЛАСТИВОСТЯМИ

The article is devoted to the justification of the use of noise protection structures with high noise – absorbing properties to reduce traffic noise. Traffic noise has a negative impact on human health and the environment, so it is necessary to implement measures to reduce its level, including the use of noise protection structures. Noise protection structures are used to protect residential buildings from traffic noise and are classified according to various criteria: stage of road design, type of structure, height, material, position of structures in the transverse profile, longitudinal profile and acoustic properties for sound reflection and absorption. In terms of acoustic properties, noise protection structures are divided into noise-reflecting and noise-absorbing screens. The characteristics of noise-reflecting and noise-absorbing screens and features of their application on highways are considered. It is shown that the sound energy from the noise-reflecting screens is reflected in the opposite direction from the protected object; the noise-absorbing screens do not cause an increase in noise on the opposite side of the road and in the cabins of passing cars due to sound energy absorption. Methods for determining the acoustic efficiency of noise protection screens of different types are presented. A comparative evaluation of the acoustic efficiency of noise-reflecting and noise-absorbing screens was performed, which confirmed the higher acoustic efficiency of noise-absorbing screens. It is shown that with the same characteristics of the noise source in the range of levels 70–100 dB under the condition of four reflections of sound in the system “vehicle – screen” the noise level behind the noise-absorbing screen will be less by about 5 dB than the noise level behind the noise-reflecting screen. Keywords: transport noise, noise protection screen, noise reflection, noise absorption, acoustic efficiency.

Revealing the effect of rounded noise protection screens with finite sound insulation on an acoustic field around linear sound sources

This paper reports studying the reduction of traffic noise by rounded noise protection screens with finite sound insulation, that is, those that can pass sound. Almost all models of acoustic screens, which are examined by analytical methods, are either direct or such that disregard the passage of sound through the screen, that is, it is assumed that the screen sound insulation is non-finite. This approach made it possible to solve the problem for a simplified model analytically but made it impossible to analyze the required sound insulation of noise protection screens. In the current paper, the problem of investigating an acoustic field around the screen whose sound insulation is finite has been stated, that is, it was taken into consideration that a sound wave propagates through the body of the screen. In addition, a given problem considers a rounded screen, rather than vertical, which is also used in different countries. Such a problem was solved by the method of partial domains. This method has made it possible to strictly analytically build a solution to the problem by simplifying it to solving an infinite system of algebraic equations, which was solved by the method of reduction. The screen model was set by the values of the density and speed of sound in the screen material. This approach has made it possible to change the acoustic impedance of the screen material and thereby change the sound insulation of the screen. That has made it possible to quantify the effect of screen sound insulation on its effectiveness. It has been shown that the efficiency of noise protection screens with finite sound insulation is approaching the efficiency of acoustically rigid screens, provided that the screen's natural sound insulation is 13–15 dB greater than the estimated efficiency of the rigid screen. The study results could make it possible to more accurately assess the effectiveness of noise protection screens. Determining the screen acoustic efficiency would make it possible to set requirements for its sound insulation characteristics. That could make it possible to select the designs of noise protection screens with minimal physical parameters, such as thickness, weight, etc.

TECHNIQUE FOR ESTIMATING THE EFFICIENCY OF NOISE PROTECTIVE ACOUSTIC SCREENS IN THE PRESENCE OF FLAT ANTI-DIFFRACTORS

To increase the efficiency of acoustic screens when protecting against acoustic noise, anti-diffractors are used to reduce the diffraction level on the upper edge of the screen. The aim of the work is to refine the mathematical model used to assess noise protection efficiency with the help of an acoustic screen with an installed one-sided flat-type anti-diffractor. The well-known techniques based on the principle of the amplitude dependence of the sound wave intensity from two sources are analyzed: a point-type noise source and a secondary cylindrical wave source - the screen edge, on which the sound wave is diffracted. Taking into account that the change in the distance between the anti-diffractor and the working point in the acoustic shadow zone is associated with a change in the diffraction angle, it is proposed to evaluate the acoustic screen effectiveness by comparing the initial sound wave propagation paths. An approach to a mathematical calculation model formation is proposed, in which the diffraction point located at the intersection of two components of the wave path to the operating point is considered to be the location of the sound wave secondary source in the area of the screen upper edge: from the noise source to the flat-type anti-diffractor installed on the upper edge of the screen, and from the anti-diffractor rear edge to the operating point. Relationships that make it possible to solve the problem of analytical assessment of noise-protective acoustic screens' effectiveness when installing anti-diffractors on their upper face in the form of flat hinged panels oriented towards the acoustic shadow are obtained.

The CONJUDOR pipeline for multiplexed knockdown of gene pairs identifies RBBP-5 as a germ cell reprogramming barrier in C. elegans.

Multiple gene activities control complex biological processes such as cell fate specification during development and cellular reprogramming. Investigating the manifold gene functions in biological systems requires also simultaneous depletion of two or more gene activities. RNA interference-mediated knockdown (RNAi) is commonly used in Caenorhabditis elegans to assess essential genes, which otherwise lead to lethality or developmental arrest upon full knockout. RNAi application is straightforward by feeding worms with RNAi plasmid-containing bacteria. However, the general approach of mixing bacterial RNAi clones to deplete two genes simultaneously often yields poor results. To address this issue, we developed a bacterial conjugation-mediated double RNAi technique ‘CONJUDOR’. It allows combining RNAi bacteria for robust double RNAi with high-throughput. To demonstrate the power of CONJUDOR for large scale double RNAi screens we conjugated RNAi against the histone chaperone gene lin-53 with more than 700 other chromatin factor genes. Thereby, we identified the Set1/MLL methyltransferase complex member RBBP-5 as a novel germ cell reprogramming barrier. Our findings demonstrate that CONJUDOR increases efficiency and versatility of RNAi screens to examine interconnected biological processes in C. elegans with high-throughput.

Improvement of the efficiency of noise protective screens due to sound absorption

The object of research is the sound field from linear sound sources around noise screens. The decrease in sound levels with the screen is primarily due to the geometric dimensions of the screen and the relative position of the screen and the sound source. The influence of these factors has been given a large number of scientific publications. However, the problematic point of such studies is that screens were considered either completely acoustically rigid or sound-absorbing.In this paper, the situation of the impedance screen is considered, quite often applied in practice. The calculation of the field around such a screen is carried out by computer simulation, which makes it easy to change the value of the acoustic impedance of the screen surface.To calculate the sound field around the screen, the finite element method is chosen. Sound-absorbing properties of the screen were determined by changing the acoustic impedance of the front side of the screen. At the same time, the screen remained acoustically opaque. Thus, an analysis is made of the influence of the sound absorption coefficient on the sound field around the screen from different heights of the screen and the distance of sound sources to the screen. This makes it possible to obtain results of sound pressure levels around screens encountered in engineering activities. Studies have shown that the use of sound-absorbing cladding for noise screens can increase their effectiveness. It is revealed that the closer the screen is located to the sound source, the greater the influence of its sound-absorbing properties. It is shown that for low frequencies the increase in screen efficiency due to sound absorption can reach 5 dB.The obtained results during the study can be used in the design of noise protective shields to reduce noise levels from traffic flows. The results obtained will be especially useful when designing screens with heights of more than 4 m

Genetic compensation in a stable slc25a46 mutant zebrafish: A case for using F0 CRISPR mutagenesis to study phenotypes caused by inherited disease.

A phenomenon of genetic compensation is commonly observed when an organism with a disease-bearing mutation shows incomplete penetrance of the disease phenotype. Such incomplete phenotypic penetrance, or genetic compensation, is more commonly found in stable knockout models, rather than transient knockdown models. As such, these incidents present a challenge for the disease modeling field, although a deeper understanding of genetic compensation may also hold the key for novel therapeutic interventions. In our study we created a knockout model of slc25a46 gene, which is a recently discovered important player in mitochondrial dynamics, and deleterious mutations in which are known to cause peripheral neuropathy, optic atrophy and cerebellar ataxia. We report a case of genetic compensation in a stable slc25a46 homozygous zebrafish mutant (hereafter referred as “mutant”), in contrast to a penetrant disease phenotype in the first generation (F0) slc25a46 mosaic mutant (hereafter referred as “crispant”), generated with CRISPR/Cas-9 technology. We show that the crispant phenotype is specific and rescuable. By performing mRNA sequencing, we define significant changes in slc25a46 mutant’s gene expression profile, which are largely absent in crispants. We find that among the most significantly altered mRNAs, anxa6 gene stands out as a functionally relevant player in mitochondrial dynamics. We also find that our genetic compensation case does not arise from mechanisms driven by mutant mRNA decay. Our study contributes to the growing evidence of the genetic compensation phenomenon and presents novel insights about Slc25a46 function. Furthermore, our study provides the evidence for the efficiency of F0 CRISPR screens for disease candidate genes, which may be used to advance the field of functional genetics.

Use of acoustics to enhance the efficiency of physical screens designed to protect downstream moving European eel (Anguilla anguilla)

AbstractEuropean eel, Anguilla anguilla (L.), is vulnerable to entrainment at a variety of man‐made intakes, including those that lead to hydropower turbines or other abstraction points. Two experiments were conducted to investigate the potential for acoustic stimuli to improve the efficiency of a vertical bar screen to guide downstream moving eel. Three underwater speakers were installed along the channel wall of an external flume, upstream of the screen. In the first experiment (a), screen guidance efficiency recorded in the presence (treatment) and absence (control) of a continuous broadband stimulus was individually compared between fish from two respective groups. Adopting a “before‐after” design, the second experiment (b) assessed individually the guidance of control eels from the group previously used in experiment 1 when exposed to a 100 Hz pulse. The majority of eels reached the bypass in both experiments with only three passing through the screen during the controls against one during each acoustic treatment. Rejection of the area adjacent to the speakers was more common during the acoustic treatment, with eels moving past the speakers more rapidly in the presence of sound. The results suggest that employing acoustic stimuli enhances the guidance efficiency of physical screens.

Efficiency of Installation of Acoustic Structures in Urban Environment

The article reviews publications within the framework of all-Russian conferences devoted to the problems of increasing the efficiency of acoustic screens in the urban environment. The proposed engineering solutions are identified and analyzed. The principles of the most rational placement of acoustic structures in the urban environment are formulated.

Response of seaward-migrating European eel (Anguilla anguilla) to an infrasound deterrent

Behavioural guidance technologies that employ stimuli to attract or repel fish offer potential to enhance, or even replace, costly physical and mechanical screens traditionally used to protect fish at river infrastructure such as hydropower and water intakes. At these structures, eel can suffer high rates of damage and mortality if entrained in pumps or turbines, or impinged on screens intended to protect them. This study used acoustic telemetry to quantify the behavioural response of adult European eel (Anguilla anguilla) to infrasound (12 Hz) under field settings. Eel (n = 50) were tracked after release immediately upstream of the forebay of a redundant hydropower facility. An infrasound deterrent located at the water intake either emitted continuously (ON) or was switched OFF. Treatment (ON/OFF) was alternated nightly over 10 consecutive nights with five eel released during a single trial conducted each night. Seventy eight percent of the 41 eel that moved downstream into the forebay passed the intake. Although the infrasound deterrent had no effect on passage rate, fine-scale differences in movement patterns were determined. When the infrasound was ON, eel trajectories were on average over twice as long with frequent erratic turns and milling behaviour (i.e. repeated lateral movements perpendicular to the principal flow direction), and they were less active within the intake channel close to the device. It is important to consider the influence of site characteristics, especially water velocities that dictate the potential for eel to respond to an acoustic field created. Infrasound deterrents that induce avoidance could be used to protect eel, either through enhancing the efficiency of physical screens or as part of multimodel behavioural guidance systems.