Now showing items 1-20 of 5012

    • Solvothermal synthesis of discrete cages and extended networks comprising {Cr(iii)3O(O2CR)3(oxime)3}2− (R = H, CH3, C(CH3)3, C14H9) building blocks

      Houton, E; Comar, P; Pitak, MB; Coles, SJ; Ryder, AG; Piligkos, S; Brechin, EK; Jones, LF (Royal Society of Chemistry (RSC), 2016-07-28)
      © 2016 The Royal Society of Chemistry. The synthesis, structural and magnetic characterisation of a family of related Cr(iii) cages are reported. Each member comprises {Cr(iii)3O(O2CR1)3(R2-sao)3}2- (R1 = H, CH3, C(CH3)3, C14H9; R2 = Me, Ph, tBu, C10H8) triangles linked by Na+ cations, resulting in either the discrete complexes [H3O][NEt4]2[NaCr(iii)6O2(O2C-C14H9)6(Naphth-sao)6] (1) and [Na4Cr(iii)6O2(O2CC(CH3)3)6(3,5-di-tBu-sao)6(MeCN)6] (3); or the extended networks [H3O]2[Na2Cr(iii)6O2(O2CH)6(Ph-sao)6(MeCN)2(H2O)2]n·4MeCN (2); [H3O][Na3Cr(iii)6O2(O2CCH3)6(Me-sao)6(MeCN)]n (4) and [Na2Cr(iii)3O(O2CCH3)3(Me-sao)3(H2O)6]n·3MeCN (5). Magnetic susceptibility data obtained for 2 and 4 reveal weak antiferromagnetic exchange between the Cr(iii) ions in the triangles.
    • Synthesis of an orthogonally protected polyhydroxylated cyclopentene from l-Sorbose

      Lo Re, D; Jones, L; Giralt, E; Murphy, P; School of Chemistry, National University of Ireland, Galway, University Road, Galway, Ireland. (Wiley, 2016-07-06)
      © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim The use of l-sorbose in the synthesis of functionalized cyclopentene derivatives was accomplished. These cyclopentene derivatives are related to those found in naturally occurring jatrophane frameworks and in other bioactive compounds. The formation of allyl α-l-sorbopyranoside was a key synthetic step. Regioselective introduction of protecting groups was followed by the hydrolysis of the allyl glycoside to furnish a fully protected acyclic l-sorbose derivative. This acyclic intermediate was subsequently used to give an orthogonally protected polyhydroxylated cyclopentene, which has potential for further synthesis of bioactive compounds. The protected cyclopentene itself showed a clear cytotoxic activity when tested against a panel of human cancer cell lines (HT29, LS174T, SW620, A549, and HeLa cells).
    • Elucidating cylindrospermopsin toxicity via synthetic analogues: An in vitro approach

      Evans, DM; Hughes, J; Jones, LF; Murphy, PJ; Falfushynska, H; Horyn, O; Sokolova, IM; Christensen, J; Coles, SJ; Rzymski, P; et al. (Elsevier, 2019-06-10)
      © 2019 Elsevier Ltd Cylindrospermopsin (CYN) is an alkaloid biosynthesized by selected cyanobacteria, the cyto- and genotoxic properties of which have been studied extensively by in vitro and in vivo experimental models. Various studies have separately established the role of uracil, guanidine and hydroxyl groups in CYN-induced toxicity. In the present study, we have prepared five synthetic analogues that all possess a uracil group but had variations in the other functionality found in CYN. We compared the in vitro toxicity of these analogues in common carp hepatocytes by assessing oxidative stress markers, DNA fragmentation and apoptosis. All the analogues tested induced generation of reactive oxygen species, lipid peroxidation (LPO) and DNA fragmentation. However, the greatest increase in LPO and increase in caspase-3 activity, an apoptosis marker, was demonstrated by an analogue containing guanidine, hydroxyl and uracil functionalities similar to those found in CYN but lacking the complex tricyclic structure of CYN. We also report a crystal structure of an analogue lacking the hydroxyl group found in CYN which does not show intramolecular H-bonding interactions between the guanidine and the uracil functionalities. The observations made in this work supports the hypothesis that CYN toxicity is a result of an interplay between both of the uracil, hydroxyl and guanidine functional groups.
    • Exploring children's physical activity behaviours according to location: A mixed-methods case study

      Khawaja, Irfan; Woodfield, Lorayne; Collins, Peter; Benkwitz, Adam; Nevill, Alan (MDPI AG, 2019-11-18)
      The school environment is ideally placed to facilitate physical activity (PA) with numerous windows of opportunity from break and lunch times, to lesson times and extracurricular clubs. However, little is known about how children interact with the school environment to engage in PA and the other locations they visit daily, including time spent outside of the school environment i.e., evening and weekend locations. Moreover, there has been little research incorporating a mixed-methods approach that captures children's voices alongside objectively tracking children's PA patterns. The aim of this study was to explore children's PA behaviours according to different locations. Sixty children (29 boys, 31 girls)-35 key stage 2 (aged 9-11) and 25 key stage 3 (aged 11-13)-wore an integrated global positioning systems (GPS) and heart rate (HR) monitor over four consecutive days. A subsample of children (n = 32) were invited to take part in one of six focus groups to further explore PA behaviours and identify barriers and facilitators to PA. Children also completed a PA diary. The KS2 children spent significantly more time outdoors than KS3 children (p = 0.009). Boys engaged in more light PA (LPA) when on foot and in school, compared with girls (p = 0.003). KS3 children engaged in significantly more moderate PA (MPA) at school than KS2 children (p = 0.006). Focus groups revealed fun, enjoyment, friends, and family to be associated with PA, and technology, costs, and weather to be barriers to PA. This mixed methodological study highlights differences in the PA patterns and perceptions of children according to age and gender. Future studies should utilize a multi-method approach to gain a greater insight into children's PA patterns and inform future health policies that differentiate among a range of demographic groups of children.
    • ‘There is anointing everywhere': An interpretative phenomenological analysis of the role of religion in the recovery of black African service users in England

      Tuffour, Isaac (Wiley, 2020-01-08)
      Introduction Religion is an important impetus for recovery. However, there has been little work examining the role of religion in recovery for black African service users (BASUs) in England. Aim The aim of this study is to explore how religion influences recovery from mental illness for BASUs in England. Method 12 black African service users were purposively selected and interviewed using face‐to‐face semi‐structured interviews. Data was analysed using interpretative phenomenological analysis (IPA). Results The study generates fascinating insights that BASUs views about mental illness and recovery are influenced by Pentecostalism and traditional African healing systems. Discussion The participants' perceptions of their mental illness experiences and recovery which are characterised by the pragmatism of Pentecostalism and cultural beliefs are consistent with what is reported in the literature. Implications for Practice The findings of the study show that broad changes are needed to accommodate the religious coping of BASUs in their recovery journey.
    • Redefining ICT embeddedness in the construction industry: Maximising technology diffusion capabilities to support agility

      Goulding, Jack; Arif, Mohammed; Ezcan, Volkan (Taylor & Francis, 2020-12-01)
      Architecture, Engineering and Construction (AEC) research often engages linear approaches for embedding/implementing/diffusing new technology into existing business systems and processes. However, developments in information and communication technology (ICT) often fail to deliver their full potential for a number of reasons. This paper presents these challenges and highlights the need to embrace equifinality as part of a structured approach for improving impact diffusion. The central tenet and foci of this work rests with the optimisation of AEC business agility. Given this, a multiple case study approach using three large construction organisations (in Turkey) was used to capture primary data from 30 respondents – representing viewpoints from three management levels: Top Management, Middle Management and First Line Management. Findings are presented in the form of a conceptual framework, the details of which highlight the constructs needed [inter alia ICT adoption/diffusion] to develop organisational: i) responsiveness, ii) flexibility and iii) corporate competence.
    • Data citation and reuse practice in biodiversity - Challenges of adopting a standard citation model

      Khan, N; Thelwall, M; Kousha, K (International Society for Scientometrics and Informetrics, 2019-08-06)
      © 2015 American Institute of Physics Inc.. All rights reserved. Openly available research data promotes reproducibility in science and results in higher citation rates for articles published with data in biological and social sciences. Even though biodiversity is one of the fields where data is frequently reused, information about how data is reused and cited is not often openly accessible from research data repositories. This study explores data citation and reuse practices in biodiversity by using openly available metadata for 43,802 datasets indexed in the Global Biodiversity Information Facility (GBIF). Quantitative analysis of dataset types and citation counts suggests that the number of studies making use of openly available biodiversity data has been increasing in a steady manner. Citation rates vary for different types of datasets based on the quality of data, and similarly to articles, it takes 2-3 years to accrue most citations for datasets. Content analysis of a random sample of unique citing articles (n=101) for 437 cited datasets in a random sample of 1000 datasets suggests that best practice for data citation is yet to be established. 26.7% of articles are mentioned the dataset in references, 12.9% are mentioned in data access statements in addition to the methods section, and only 2% are mentioned in all three sections, which is important for automatic extraction of citation information. Citation practice was inconsistent especially when a large number of subsets (12—50) were used. This calls for adoption of a standard citation model for this field to provide proper attribution when using subsets of data.
    • Gum feeder as environmental enrichment for zoo marmosets and tamarins

      Regaiolli, Barbara; Angelosante, Chiara; Marliani, Giovanna; Accorsi, Pier Attilio; Vaglio, Stefano; Spiezio, Caterina (Wiley, 2020-01-15)
      Tamarins and marmosets are small‐bodied social callitrichines. Wild callitrichines feed on exudates, such as sap and gum; particularly, marmosets are mainly gummivores, while tamarins consume gums only occasionally and opportunistically. Zoo marmosets and tamarins are usually provided with gum arabic as an alternative to the exudates normally found in the wild. The aim of this study was to evaluate the effects of a gum feeder on the behavior and well‐being of four zoo‐managed callitrichines. We studied four cotton‐top tamarins (Saguinus oedipus), four red‐handed tamarins (S. midas), two pygmy marmosets (Cebuella pygmaea), and three Geoffroy's marmosets (Callithrix geoffroyi) housed at Parco Natura Viva (Italy). We conducted the study over two different periods, a baseline (control, without the gum feeder) and then a gum feeder (when the gum feeder was provided) period. We used continuous focal animal sampling to collect behavioral data, including durations of social and individual behaviors. We collected 240 min of observations per period per study subject, with a total of 3,120 min for all the subjects in the same period and of 6,240 min in both periods. We analyzed data by using nonparametric statistical tests. First, we found that the gum feeder promoted species‐specific behaviors, such as exploration, and diminished self‐directed behaviors, suggesting an enriching effect on tamarin and marmoset behavior. Moreover, in red‐handed tamarins, the provision of the gum feeder reduced the performance of self‐directed and abnormal behavior, specifically coprophagy. These results confirm that gum feeders are effective foraging enrichment tools for zoo marmosets and tamarins.
    • Afraid to leave the house: issues leading to social exclusion and loneliness for people with a learning disability

      Tilly, L (Emerald, 2019-09-26)
      © 2019, Emerald Publishing Limited. Purpose: Tackling social exclusion, which can lead to social isolation and loneliness, is an important current issue. People with a learning disability have a right to be full members of their communities, yet often experience social exclusion. Community connections play a key role in people developing reciprocal relationships. It is therefore important to know the barriers to full inclusion. The paper aims to discuss this issue. Design/methodology/approach: This paper builds on an inclusive research project exploring these issues (Mooney et al., 2019) and aims to place that study’s main findings in a broader academic, policy and practice context. Findings: Whilst there is a wide range of literature about social exclusion, lack of friendships and loneliness experienced by people with a learning disability, there is a gap in knowledge regarding some of the specific social barriers that prevent wider social inclusion, and therefore opportunities to make and keep friends. Originality/value: This paper relates the findings of an inclusive research project to the current literature. It identifies the social barriers that limit community involvement and draws on the experience of people with a learning disability to find possible ways forward.
    • Impact of anthropogenic factors on affiliative behaviors among bonnet macaques

      Balasubramaniam, Krishna N; Marty, Pascal R; Arlet, Małgorzata E; Beisner, Brianne A; Kaburu, Stefano; Bliss-Moreau, Eliza; Kodandaramaijah, Ullasa; McCowan, Brenda (Wiley-Blackwell, 2020-12-01)
      Objectives: In primates, allogrooming and other affiliative behaviors confer many benefits and may be influenced by many socioecological factors. Of these, the impact of anthropogenic factors remain relatively understudied. Here we ask whether interactions with humans decreased macaques’ affiliative behaviors by imposing time-constraints, or increased these behaviors on account of more free-/available-time due to macaques’ consumption of high-energy human foods. Materials and Methods: In Southern India, we collected data on human-macaque and macaque-macaque interactions using focal-animal sampling on two groups of semi-urban bonnet macaques for 11 months. For each macaque within each climatic season, we calculated frequencies of human-macaque interactions, rates of monitoring human activity and foraging on anthropogenic food, dominance ranks, grooming duration, number of unique grooming partners, and frequencies of other affiliative interactions. Results: We found strong evidence for time-constraints on grooming. Macaques that monitored humans more groomed for shorter durations and groomed fewer partners, independent of their group membership, sex, dominance rank, and season. However, monitoring humans had no impact on other affiliative interactions. We found no evidence for the free-time hypothesis foraging on anthropogenic food was unrelated to grooming and other affiliation. Discussion: Our results are consistent with recent findings on other urban-dwellingspecies/populations. Macaques in such environments may be especially reliant on other forms of affiliation that are of short duration (e.g. coalitionary support, lip-smacking) and unaffected by time-constraints. We stress on the importance of evaluating human impact on inter-individual differences in primate/wildlife behavior for conservation efforts.
    • Why does ethics matter in participatory health?

      Bond, Carol; DENECKE, Kerstin; LUQUE, Luis Fernandez; GABARRON, Elia; LOPEZ-CAMPOS, Guillermo (European Federation of Medical Informatics, 2020-04-28)
      Social media and participatory health has emerged as a promising tool for health, including developing diagnostic tools and therapeutic interventions. In the realm of online health care delivery, artificial intelligence based counseling apps now enable patients to consult with a chatbot instead of an actual therapist. However, several ethical issues and implications became relevant with this shift to digital interventions and healthcare delivery. This panel will describe ethical issues related to recent developments in participatory health and social media including the digital exposome, importance of involving patients in the design of AI-based applications and ethics of social media research in healthcare.
    • Trouble on the road: Finding reasons for commuter stress from tweets

      Gopalakrishna Pillai, Reshmi; Thelwall, Mike; Orasan, Constantin (Association for Computational Linguistics, 2018-11-30)
      Intelligent Transportation Systems could benefit from harnessing social media content to get continuous feedback. In this work, we implement a system to identify reasons for stress in tweets related to traffic using a word vector strategy to select a reason from a predefined list generated by topic modeling and clustering. The proposed system, which performs better than standard machine learning algorithms, could provide inputs to warning systems for commuters in the area and feedback for the authorities.
    • Numerical modelling to predict fracturing rock (Thanet chalk) due to naturally occurring faults and fluid pressure

      Eshiet, KII; Welch, M; Sheng, Y (Elsevier, 2018-07-30)
      © 2018 Elsevier Ltd Outcrop mapping of a chalk cliff and wavecut platform in Thanet, Southeast England show a complex fracture pattern that seems to be controlled by meso-scale strike-slip faults within the chalk. The response of these faults to changes to in situ stress and fluid pressure is thought to control the nucleation and propagation of fractures in the chalk. In this study the DEM (Discrete Element Method) technique has been employed as a follow up to previous field and numerical (boundary and finite element method) investigations to ascertain the role of the faults in the initiation and nucleation of fractures The role of fluid pressure, in-situ stress, and fault geometry are recognised as focal factors. The generation of localised areas of tensile stresses due to fluid pressure and stress perturbations have been shown to cause the initiation of fractures around the fault bends. For releasing bends, localised tensile stresses tend to occur along the central segment of the fault bend, whereas for restraining bends, tensile stresses are more likely to develop on the outer edges of the fault bend. The dissimilarity in the fracturing process due to differences in the geometry of pre-existing faults demonstrates the significance of both fault geometry and fluid behaviour in controlling fracturing.
    • Micro-damage evolution and macro-mechanical property degradation of limestone due to chemical effects

      Li, H; Zhong, Z; Liu, X; Sheng, Y; Yang, D (Elsevier, 2018-08-31)
      © 2018 Nuclear Magnetic Resonance (NMR) imaging in combination with mechanical tests are carried out to investigate the influence of chemical solutions on porosity change, micro damage and macro mechanical property degradation of limestone samples under external stress. The NMR images and T2 values for compression stage, micro damages emergence stage, micro damages development stage and fracture and collapse stage are obtained and analysed. The results of the corrosive influence of chemical solutions with different pH values and immersion periods on the mechanical property degradation of limestone samples are investigated. By choosing porosity as the damage variable, the micro damage of the samples during triaxial compression are calculated. It can be concluded that pH values of the chemical solutions change the porosity and micro damage evolution of the rock, which is the root reason for its mechanical properties degradation. The chemical erosion also has a significant influence on the micro crack propagation in the limestone samples under triaxial compression.
    • The intrinsic value of formative assessment and feedback as learning tools in the acquisition and improvement of a practical legal skill

      Jones, Dawn (Taylor & Francis, 2020-12-01)
      Teaching a practical legal skill in a classroom setting can be challenging, it is an attempt to teach the practical in a theoretical way to students who are unlikely to have undertaken this type of practical task previously. The module considered in this research, Practical Legal Drafting, comprises taught sessions that first introduce the ‘rules’ of legal drafting and then allow the development of key skills. The module includes tutor led taught sessions, student in class group and individual activities and ongoing tutor verbal feedback in class, followed by a formative assessment, extensive specific individual written and generic online feedback, and finally face to face feedback on the formative assessment. This combination forms the learning process for the module considered in this study. The formative assessment is not a compulsory element of the module, the data for three academic years was analysed to determine whether those students who undertook the formative assessment were more successful in the summative assessment than those students who did not and whether it could therefore be said that this was evidence that the formative assessment was beneficial as a teaching tool. The student’s engagement with the feedback available on the VLE was also assessed to determine whether any conclusions could be reached about the impact this may or may not have on improved student performance.
    • Does psychological functioning mediate the relationship between bullying involvement and weight loss preoccupation in adolescents? A two-stage cross-sectional study

      Lee, Kirsty; Guy, Alexa; Dale, Jeremy; Wolke, Dieter (Springer Science and Business Media LLC, 2017-03-24)
      Background Adolescent bullying is associated with a range of adversities for those who are bullied i.e., victims and bully-victims (e.g., those who bully others and get victimised), including reduced psychological functioning and eating disorder symptoms. Bullies are generally well-adjusted psychologically, but previous research suggests that bullies may also engage in problematic diet behaviours. This study investigates a) whether adolescents involved in bullying (bullies, victims, bully-victims) are at increased risk of weight loss preoccupation, b) whether psychological functioning mediates this relationship and c) whether sex is a key moderator. Method A two-stage design was used. In stage 1, adolescents (n = 2782) from five UK secondary schools were screened for bullying involvement using self and peer reports. In stage 2, a sample of bullies, victims, bully-victims and uninvolved adolescents (n = 767) completed a battery of assessments. The measures included the eating behaviours component of the Child and Adolescent Psychiatric Assessment, which was reduced to one factor (weight loss preoccupation) and used as the outcome variable. Measures of self-esteem, body-esteem and emotional problems were reduced to a latent (mediator) variable of psychological functioning. Multi-group analysis examined the effects of sex and all models were adjusted for covariates (BMI, pubertal stage, age, parental education and ethnicity). Results Bullies, victims and bully-victims were at increased risk of weight loss preoccupation compared to adolescents uninvolved in bullying. The mechanism by which bullying involvement related to increased weight loss preoccupation varied by bullying role: in bullies the effect was direct, in victims the effect was indirect (via reduced psychological functioning) and in bully-victims the effect was both direct and indirect. Sex significantly moderated the relationship in bullies: weight loss preoccupation was only statistically significant in bullies who were boys. Conclusion Bullying involvement during adolescence is associated with weight loss preoccupation. Bullies are likely driven by a desire to increase attractiveness and social status; whereas weight loss preoccupation in bullied adolescents may have maladaptive influences on diet and exercise behaviours due to its association with reduced psychological functioning. Future research should consider peer victimisation as a potential modifiable risk factor for reduced psychological functioning and weight loss preoccupation, which if targeted, may help to prevent maladaptive diet and exercise behaviours.
    • Bullying and negative appearance feedback among adolescents: Is it objective or misperceived weight that matters?

      Lee, Kirsty; Dale, Jeremy; Guy, Alexa; Wolke, Dieter (Elsevier BV, 2017-12-28)
      This study investigated (1) whether involvement in bullying as a bully, victim or bully-victim was associated with objectively measured overweight or underweight, or whether it was related to weight misperception (i.e., inaccurate perceptions), and (2) whether appearance-specific feedback mediated the relationship between bullying and weight misperception. In Stage 1, 2782 adolescents aged 11–16 years from British secondary schools were screened for peer bullying and victimisation. In Stage 2, 411 adolescents with weight and height data (objective n = 319, self-report n = 92) also self-reported on their weight perception and appearance-specific feedback. Neither bullying nor victimisation were related to objective underweight or overweight. Victims were at increased odds of overweight misperception, while bully-victims were at increased odds of underweight misperception. Additionally, there was an indirect effect of appearance feedback on overweight misperception in bully-victims. Both victims and bully-victims are at increased risk of weight misperception, posing further detrimental effects to their health and wellbeing.
    • Adolescent desire for cosmetic surgery

      Lee, Kirsty; Guy, Alexa; Dale, Jeremy; Wolke, Dieter (Ovid Technologies (Wolters Kluwer Health), 2017-05-31)
      Background: Adolescent bullying may be a key driver of interest in cosmetic surgery. This study examined the extent of such interest and whether any effect was sex-specific, and examined psychological functioning as a potential mechanism through which bullying involvement may lead to a wish for cosmetic surgery. Methods: A two-stage design was used. In the first stage, 2782 adolescents (aged 11 to 16 years) were screened for bullying involvement using self-reports and peer nominations. In the second stage, 752 adolescents who were bullies, victims, bully-victims, or uninvolved in bullying reported their desire for cosmetic surgery. Psychological functioning was constructed as a composite of self-esteem and emotional problems (assessed at stage 1) and body-esteem scores (assessed at stage 2). Results: Adolescents involved in bullying in any role were significantly more interested in cosmetic surgery than uninvolved adolescents. Desire for cosmetic surgery was greatest in adolescents who were bullied (victims and bully-victims) and girls. Desire for cosmetic surgery was highest in girls, but sex did not interact with bullying role. Being victimized by peers resulted in poor psychological functioning, which increased desire for cosmetic surgery. In contrast, desire for cosmetic surgery in bullies was not related to psychological functioning, which was in the normal range. Conclusions: Bullying victimization is related to poor psychological functioning, and both are related to a greater desire for cosmetic surgery in adolescents. Cosmetic surgeons should screen candidates for psychological vulnerability and may want to include a short screening questionnaire for a history of peer victimization.
    • Cyberbullying: a storm in a teacup?

      Wolke, Dieter; Lee, Kirsty; Guy, Alexa (Springer Science and Business Media LLC, 2017-02-10)
      Cyberbullying has been portrayed as a rising ‘epidemic’ amongst children and adolescents. But does it create many new victims beyond those already bullied with traditional means (physical, relational)? Our aim was to determine whether cyberbullying creates uniquely new victims, and whether it has similar impact upon psychological and behavioral outcomes for adolescents, beyond those experienced by traditional victims. This study assessed 2745 pupils, aged 11–16, from UK secondary schools. Pupils completed an electronic survey that measured bullying involvement, self-esteem and behavioral problems. Twenty-nine percent reported being bullied but only 1% of adolescents were pure cyber-victims (i.e., not also bullied traditionally). Compared to direct or relational victims, cyber-victimization had similar negative effects on behavior (z = −0.41) and self-esteem (z = −0.22) compared to those not involved in bullying. However, those bullied by multiple means (poly-victims) had the most difficulties with behavior (z = −0.94) and lowest self-esteem (z = −0.78). Cyberbullying creates few new victims, but is mainly a new tool to harm victims already bullied by traditional means. Cyberbullying extends the reach of bullying beyond the school gate. Intervention strategies against cyberbullying may need to include approaches against traditional bullying and its root causes to be successful.
    • Water channel pore size determines exclusion properties but not solute selectivity

      Kitchen, Philip; Salman, Mootaz M; Pickel, Simone U; Jennings, Jordan; Törnroth-Horsefield, Susanna; Conner, Matthew T; Bill, Roslyn M; Conner, Alex C (Springer Science and Business Media LLC, 2019-12-30)
      Aquaporins (AQPs) are a ubiquitous family of transmembrane water channel proteins. A subgroup of AQP water channels also facilitates transmembrane diffusion of small, polar solutes. A constriction within the pore, the aromatic/arginine (ar/R) selectivity filter, is thought to control solute permeability: previous studies on single representative water channel proteins suggest narrow channels conduct water, whilst wider channels permit passage of solutes. To assess this model of selectivity, we used mutagenesis, permeability measurements and in silico comparisons of water-specific as well as glycerol-permeable human AQPs. Our studies show that single amino acid substitutions in the selectivity filters of AQP1, AQP4 and AQP3 differentially affect glycerol and urea permeability in an AQP-specific manner. Comparison between in silico-calculated channel cross-sectional areas and in vitro permeability measurements suggests that selectivity filter cross-sectional area predicts urea but not glycerol permeability. Our data show that substrate discrimination in water channels depends on a complex interplay between the solute, pore size, and polarity, and that using single water channel proteins as representative models has led to an underestimation of this complexity.