Micro- and nanoplastic pollution of freshwater and wastewater treatment systems

Plastic waste is a widespread and persistent global challenge with negative impacts on the environment, economy, human health and aesthetics. Plastic pollution has been a focus of environmental research over the past few decades, particularly in relation to macroplastics that are easily visible by the naked eye. More recently, smaller plastic waste at the micro- and nanoscale has become of increasing concern, resulting in extensive investment in research to advance knowledge on the sources, distribution, fate and impact of these materials in aquatic systems. However, owing to their small sizes and a lack of unified methods, adequate quantitative and qualitative assessment has been difficult. Furthermore, most of the microplastic surveys available to date have focussed in the marine environment while scarce knowledge exists of freshwater systems. Because the majority of marine debris originates on land, the role of wastewater treatment systems and natural fluvial vectors in delivering these emerging contaminants to the environment should be explored. Considering fundamental aspects pertaining to microplastic sources, distribution, mobility and degradation in these systems is crucial for developing effective control measures and strategies to mitigate the discharge of these particles to the sea

Men with intellectual disabilities with a history of sexual offending: empathy for victims of sexual and non-sexual crimes

Background: The objectives were (a) to compare the general empathy abilities of men with intellectual disabilities (IDs) who had a history of sexual offending to men with IDs who had no known history of illegal behaviour, and (b) to determine whether men with IDs who had a history of sexual offending had different levels of specific victim empathy towards their own victim, in comparison to an unknown victim of sexual crime, and a victim of non-sexual crime, and make comparison to non-offenders. Methods: Men with mild IDs (N = 35) were asked to complete a measure of general empathy and a measure of specific victim empathy. All participants completed the victim empathy measure in relation to a hypothetical victim of a sexual offence, and a non-sexual crime, while additionally, men with a history of sexual offending were asked to complete this measure in relation to their own most recent victim. Results: Men with a history of sexual offending had significantly lower general empathy, and specific victim empathy towards an unknown sexual offence victim, than men with no known history of illegal behaviour. Men with a history of sexual offending had significantly lower victim empathy for their own victim than for an unknown sexual offence victim. Victim empathy towards an unknown victim of a non-sexual crime did not differ significantly between the two groups. Conclusions: The findings suggest that it is important include interventions within treatment programmes that attempt to improve empathy and perspective-taking

Microscopy and elemental analysis characterisation of microplastics in sediment of a freshwater urban river in Scotland, UK

Understanding of the sources, fate, and impact of microplastics (MPs, < 5 mm) remains limited, particularly in freshwater environments, while limited comparability across available surveys hinders adequate monitoring and risk assessment of these contaminants. Here, the distribution of microscopic debris in an urban river close to the marine environment in the West of Scotland was investigated to assess concentration and distribution of primary and secondary MPs. Also, the efficiency of light and scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS) was evaluated for characterisation and quantification of MPs sized 2.8 mm–11 μm. Bank sediment samples were collected twice from the River Kelvin in Glasgow and were size-fractionated and processed for extraction of MPs by density separation. Sample MPs spiking and use of procedural blanks allowed the influence of processing on field data quality to be considered. Total abundances were 161–432 MPs kg−1 dry sediment, with fibres as the dominant type, comprising > 88% of total counts. Nevertheless, fibres in blanks suggest potential contributions from atmospheric contamination. Moreover, fibres concentrated mainly in fractions < 0.09 mm suggesting that their fate may be influenced by drivers of fine sediment dynamics in rivers. While no primary MPs were observed, metallic and glass pellets were present in high abundances in settled material and could be easily misidentified by visual inspection, demonstrating that compositional analysis is needed to avoid analytical errors from MP misidentification and overestimation. SEM-EDS allowed for a quick screening of plastic vs non-plastic pellets and improved identification of smaller fragments, whereas more advanced techniques are needed for proper identification of fibres. This study is the first to report on MPs in freshwater rivers in Scotland and suggests that diffuse sources of pollution may be delivering secondary MPs to the river. Their sources, fate, and risk in these systems will thus warrant further attention

Identification of genes differentially expressed as result of adenovirus type 5- and adenovirus type 12-transformation

Background: Cells transformed by human adenoviruses (Ad) exhibit differential capacities to induce tumours in immunocompetent rodents; for example, Ad12-transformed rodent cells are oncogenic whereas Ad5-transformed cells are not. The E1A gene determines oncogenic phenotype, is a transcriptional regulator and dysregulates host cell gene expression, a key factor in both cellular transformation and oncogenesis. To reveal differences in gene expression between cells transformed with oncogenic and non-oncogenic adenoviruses we have performed comparative analysis of transcript profiles with the aim of identifying candidate genes involved in the process of neoplastic transformation. Results: Analysis of microarray data revealed that a total of 232 genes were differentially expressed in Ad12 E1- or Ad5 E1-transformed BRK cells compared to untransformed baby rat kidney (BRK) cells. Gene information was available for 193 transcripts and using gene ontology (GO) classifications and literature searches it was possible to assign known or suggested functions to 166 of these identified genes. A subset of differentially-expressed genes from the microarray was further examined by real-time PCR and Western blotting using BRK cells immortalised by Ad12 E1A or Ad5 E1A in addition to Ad12 E1- or Ad5 E1-transformed BRK cells. Up-regulation of RelA and significant dysregulation of collagen type I mRNA transcripts and proteins were found in Ad-transformed cells. Conclusion: These results suggest that a complex web of cellular pathways become altered in Ad-transformed cells and that Ad E1A is sufficient for the observed dysregulation. Further work will focus on investigating which splice variant of Ad E1A is responsible for the observed dysregulation at the pathway level, and the mechanisms of E1A-mediated transcriptional regulation

Electromyographic evaluation of muscle firing patterns in the ridden horse during jumping as an objective method of informing current jump training programmes

The sport of show jumping (SJ) places great physical demands on the equine athlete. Despite this, selection and training strategies for the equine jumping athlete are largely based on anecdotal methods. SJ horses are generally selected at a young age based on quality of movement and jump technique. Numerous studies have provided information on the biomechanical demands of jumping. However, research has not sufficiently investigated how quality jump technique and performance may be improved through training in the SJ horse. The horse’s ability to execute the physical demands required for SJ is greatly influenced by muscular adaptation to training. Scientifically evidenced training programmes incorporate exercises, which mimic the duration, intensity, neuromuscular activity and movement patterns that are experienced during competition. However, a lack of understanding on how equine muscles facilitate the jumping effort represents a major gap in knowledge. Therefore, the aim of this thesis was to explore muscle firing patterns, which facilitate “quality” movement during different phases of the equine jump and to determine whether these support traditional training methods in the jumping horse. Surface electromyography (sEMG) and three-dimensional (3D) kinematic data were collected synchronously from a group of elite and non-elite jumping horses during canter and jump trials over a 1.0m fence. sEMG data were collected from the Superficial Gluteal, Biceps Femoris (vertebral head), Triceps Brachii (long head), Trapezius (cervical head), and Splenius. Lack of standardised methods within equine sEMG research represents a major gap in knowledge. Therefore, four original studies were conducted to develop optimal methods for the acquisition and analysis of sEMG data collected from equine subjects during jumping. These methods were employed in the main study of the thesis. An original questionnaire was designed to define “quality” movement and “traditional” training methods in the jumping horse, based on the opinions and preferences of highly qualified equestrians. Questionnaire results revealed obvious preferences for specific movement traits, which were used to inform kinematic data analysis. The incorporation of questionnaire findings ensured that research had practical application within the equine industry. Kinematic data analysis in the main study of the thesis revealed that “quality” movement traits between elite and non-elite athletes were largely non-significant. These findings suggested that movement alone may not be an accurate method for differentiating between good and poor jump technique and performance. However, sEMG data revealed differences in neuromuscular strategies between groups, which had a direct influence on jump technique. Elite horses exhibited the greatest capacity for generation of muscular force and power, particularly in the hindlimb during jump take-off. This finding was evidenced by greater: integrated EMG (iEMG), average rectified value, and peak amplitude data. As a result, “quality” jump technique was facilitated through greater vertical displacement and velocity of the centre of mass (CM) during jump take-off and suspension phases. These findings provide objective evidence for equestrians to place greater emphasis on strength (anaerobic training), as questionnaire findings revealed a trend for largely aerobic training programmes in the jumping horse. Findings also suggest that equestrians prioritise movement traits, which are indicative of muscular strength when selecting equine jumping athletes. This study has demonstrated the benefits of sEMG for the development of scientifically evidenced training and selection processes in the equine SJ athlete

Reinstatement of extinguished fear by an unextinguished conditional stimulus

Anxiety disorders are often treated using extinction-based exposure therapy, but relapse is common and can occur as a result of reinstatement, whereby an aversive “trigger” can reinstate extinguished fear. Animal models of reinstatement commonly utilize a Pavlovian fear conditioning procedure, in which subjects are first trained to fear a conditional stimulus (CS) by pairing it with an aversive unconditional stimulus (US), and then extinguished by repeated presentations of the CS alone. Reinstatement is typically induced by exposing subjects to an aversive US after extinction, but here we show that exposure to a non-extinguished CS can reinstate conditional fear responding to an extinguished CS, a phenomenon we refer to as “conditional reinstatement” (CRI). Rats were trained to fear two CSs (light and tone) and subsequently underwent extinction training to only one CS (counterbalanced). Presenting the unextinguished CS (but not a novel cue) immediately after extinction reinstated conditional fear responding to the extinguished CS in a test session given 24 h later. These findings indicate that reinstatement of extinguished fear can be triggered by exposure to conditional as well as unconditional aversive stimuli, and this may help to explain why relapse is common following clinical extinction therapy in humans. Further study of CRI using animal models may prove useful for developing refined extinction therapies that are more resistant to reinstatement

Identification of microplastics in a large water volume by integrated holography and Raman spectroscopy

Funding Japan Science and Technology Agency SICORP (JPMJSC1705); Natural Environment Research Council (NE/R01227X/1); Kajima Foundation (Overseas research grant); Japan Society for the Promotion of Science (18H03810, 18K13934); Kurita Water and Environment Foundation (17B030).Peer reviewedPublisher PD