Alternative behavioral measures of postconflict affiliation

Animals are known to affiliate after conflicts rather than avoid each other. Affiliation can occur between former opponents or between a former opponent and a third-party, and is more common between individuals with high-quality relationships. We investigate postconflict (PC) affiliation in 3 species of corvid (crows) to examine how both sociality and analysis method influence this behavior. We hypothesized that 1) there will be no former opponent affiliation because the highest-quality relationships in these species are between mates who never fight, therefore eliminating the need to repair this relationship; and 2) colonial rooks and jackdaws will show third-party affiliation with partners, whereas the territorial Eurasian jays will not show this behavior because they lack high-quality relationships outside of the breeding season when their data were collected. PC affiliation is generally analyzed using the latency to first affiliative contact, however this method has limitations. We explore 2 different measures: the frequency and duration of affiliation across each observation session. There was no evidence of former opponent affiliation in rooks or jays, but some in jackdaws according to affiliation durations. Rooks and jackdaws showed third-party affiliation with mates according to affiliation frequencies and durations, and jays showed third-party affiliation according to affiliation durations, but with any individual, not just mates. We suggest that PC affiliation is best investigated using more than first affiliation latencies, and that the frequency and duration of affiliation may indicate whether affiliation is used to address PC stressCJL was supported by the Gates Cambridge Trust and Murray Edwards College. The research was supported by grants from the BBSRC, the Royal Society, and the University of Cambridge. Birds were hand-raised under a Natural England permit, jays were included on the Home Office Project Licence (80/1975) and rooks and jackdaws were kept under a University of Cambridge non-regulated procedures licence. All activities in this study were carried out in accordance with these licences.This is the author accepted manuscript. The final version is available from Oxford University Press via https://doi.org/10.1234/10.1093/beheco/ars14

Rook, But Not Jackdaw, Post-Conflict Third-Party Affiliation Reduces Aggression for Aggressors

Post-conflict (PC) affiliation refers to positive social interactions that occur after fights. Although this behavior has been widely studied, its functions are rarely tested. We examine a potential function of PC third-party affiliation (affiliation between former opponents and bystanders) in rooks and jackdaws by investigating the hypothesis that conflicts lead to further aggression and that PC third-party affiliation increases to reduce such aggression. The results show that PC affiliation reduces PC aggression for rook aggressors who were less likely to receive aggression after conflicts when they were affiliating with another vs. when they were alone. The opposite result was found for victims of both species who received more aggression after conflicts, and this aggression was not reduced by the act of affiliating. Finally, for jackdaw aggressors, the amount of aggression received after conflicts was not influenced by whether the individual was affiliating or alone, indicating that PC third-party affiliation may serve a function that we did not examine. These findings highlight the importance of investigating functional differences in PC affiliative behavior according to the role played in the conflict.We are grateful for financial support from the Gates Cambridge Scholar-ship and Murray Edwards College (CJL), and the BBSRC, the Royal Society, and the University of Cambridge (NSC).This is the author accepted manuscript. The final version is available from Wiley via https://doi.org/10.1111/eth.12078IN

Measurement of Scleral Thickness in Humans Using Anterior Segment Optical Coherent Tomography

Anterior segment optical coherent tomography (AS-OCT, Visante; Zeiss) is used to examine meridional variation in anterior scleral thickness (AST) and its association with refractive error, ethnicity and gender. Scleral cross-sections of 74 individuals (28 males; 46 females; aged between 18-40 years (27.7±5.3)) were sampled twice in random order in 8 meridians: [superior (S), inferior (I), nasal (N), temporal (T), superior-temporal (ST), superior-nasal (SN), inferior-temporal (IT) and inferior-nasal (IN)]. AST was measured in 1mm anterior-toposterior increments (designated the A-P distance) from the scleral spur (SS) over a 6mm distance. Axial length and refractive error were measured with a Zeiss IOLMaster biometer and an open-view binocular Shin-Nippon autorefractor. Intra- And inter-observer variability of AST was assessed for each of the 8 meridians. Mixed repeated measures ANOVAs tested meridional and A-P distance differences in AST with refractive error, gender and ethnicity. Only right eye data were analysed. AST (mean±SD) across all meridians and A-P distances was 725±46μm. Meridian SN was the thinnest (662±57μm) and I the thickest (806 ±60μm). Significant differences were found between all meridians (p<0.001), except S:ST, IT:IN, IT:N and IN:N. Significant differences between A-P distances were found except between SS and 6 mm and between 2 and 4mm. AST measurements at 1mm (682±48 μm) were the thinnest and at 6mm (818±49 μm) the thickest (p<0.001); a significant interaction occurred between meridians and A-P distances (p<0.001). AST was significantly greater (p<0.001) in male subjects but no significant differences were found between refractive error or ethnicity. Significant variations in AST occur with regard to meridian and distance from the SS and may have utility in selecting optimum sites for pharmaceutical or surgical intervention

Eurasian jays do not copy the choices of conspecifics, but they do show evidence of stimulus enhancement

Corvids (birds in the crow family) are hypothesised to have a general cognitive tool-kit because they show a wide range of transferrable skills across social, physical and temporal tasks, despite differences in socioecology. However, it is unknown whether relatively asocial corvids differ from social corvids in their use of social information in the context of copying the choices of others, because only one such test has been conducted in a relatively asocial corvid. We investigated whether relatively asocial Eurasian jays ($\textit{Garrulus glandarius}$) use social information (i.e., information made available by others). Previous studies have indicated that jays attend to social context in their caching and mate provisioning behaviour; however, it is unknown whether jays copy the choices of others. We tested the jays in two different tasks varying in difficulty, where social corvid species have demonstrated social information use in both tasks. Firstly, an object-dropping task was conducted requiring objects to be dropped down a tube to release a food reward from a collapsible platform, which corvids can learn through explicit training. Only one rook and one New Caledonian crow have learned the task using social information from a demonstrator. Secondly, we tested the birds on a simple colour discrimination task, which should be easy to solve, because it has been shown that corvids can make colour discriminations. Using the same colour discrimination task in a previous study, all common ravens and carrion crows copied the demonstrator. After observing a conspecific demonstrator, none of the jays solved the object-dropping task, though all jays were subsequently able to learn to solve the task in a non-social situation through explicit training, and jays chose the demonstrated colour at chance levels. Our results suggest that social and relatively asocial corvids differ in social information use, indicating that relatively asocial species may have secondarily lost this ability due to lack of selection pressure from an asocial environment.RM and NSC received funding from the European Research Council under the European Union’s Seventh Framework Programme (FP7/2007-2013) / ERC Grant Agreement No. 3399933, awarded to NSC. CJL was funded by the Leverhulme Trust and Isaac Newton Trust with a Leverhulme Early Career Fellowship

Conformation of the anterior segment in human myopia.

PURPOSE: Topography of the in vivo anterior segment is of relevance in understanding its role in myopia and in the development of ocular surgical procedures. Using 3D magnetic resonance (MR) images of the human eye, regional variations in surface area (SA) and bulbosity of four anterior segment regions were investigated in association with refractive status (Rx), axial length (AL) and total ocular volume (OV). METHODS: T2-weighted ocular MR images from 43 adults aged 18-40 years (mean ± SD; 28.65 ± 6.20) comprising 20 non-myopes (≥-0.50) 0.57 ± 1.38 and 23 myopes (<-0.50) -6.37 ± 4.23 MSE (D) were collected. 2D representations of each quadrant (superior-temporal [ST], superior-nasal [SN], inferior-temporal [IT] and inferior-nasal [IN]) of the anterior section (3.5-9 mm) were fitted with second-order polynomials. Polynomials were integrated and rotated about the x-axis to generate SA; dividing the SA by 4 provided relative quadrantial SA. The x2 coefficient provides indices of bulbosity. OV was derived from the 3D MRI scans. Rx and AL were measured using cycloplegic autorefraction and the Zeiss IOLMaster, respectively. One- and two-way repeated-measures ANCOVAs tested differences in SA and bulbosity for Rx, gender, ethnicity and age. Pearson's correlation coefficient tested the relationship between MRI-derived metrics and biometry. RESULTS: Significant differences in SA were observed between quadrants (p < 0.001) with differences between ST versus IN, IN versus IT and SN versus IT. An interaction effect (p = 0.01) for Rx suggested smaller temporal (ST and IT) and larger nasal (SN and IN) SA in myopes. AL and myopic Rx were negative correlated (p < 0.05) with SA at IN, SN and IT. OV was significantly associated with SA at ST. Bulbosity showed no regional differences nor an effect of AL or Rx. CONCLUSION: Significant regional variation in SA exists across the anterior segment that is modulated by Rx and AL. It is unclear whether these structural characteristics are a precursor or consequence of myopia and may warrant investigation when developing biomechanical interventions

Sampling and measurement methods for a study of childhood refractive error in a UK population

International audienceBackground There is a paucity of data describing the prevalence of childhood refractive error in the United Kingdom. The Northern Ireland Childhood Errors of Refraction study, along with its sister study the Aston Eye Study, are the first population-based surveys of children using both random cluster sampling and cycloplegic autorefraction to quantify levels of refractive error in the United Kingdom. Methods Children aged 6-7 years and 12-13 years were recruited from a stratified random sample of primary and post-primary schools, representative of the population of Northern Ireland as a whole. Measurements included assessment of visual acuity, oculomotor balance, ocular biometry and cycloplegic binocular open-field autorefraction. Questionnaires were used to identify putative risk factors for refractive error. Results 399 (57%) of 6-7 years and 669 (60%) of 12-13 years participated. School participation rates did not vary statistically significantly with the size of the school, whether the school is urban or rural, or whether it is in a deprived/non-deprived area. The gender balance, ethnicity and type of schooling of participants are reflective of the Northern Ireland population. Conclusions The study design, sample size and methodology will ensure accurate measures of the prevalence of refractive errors in the target population and will facilitate comparisons with other population-based refractive data

Mucosal atrophy in collagenous colitis: a case report

<p>Abstract</p> <p>Background</p> <p>Mucosal atrophy as a potential cause of impaired colonic compliance has not yet been described as a complication in Collagenous Colitis (CC).</p> <p>Case presentation</p> <p>We present a 51-year-old female patient with a 20-year history of diarrhea and diagnosed with CC ten years prior to her presentation. We reviewed reports from three colonoscopies performed after the diagnosis. Overall 12 biopsies obtained in the last two colonoscopies were re-analyzed by two pathologists blinded to the aim of the study. Besides the typical histological findings of CC, the endoscopic appearance was normal, and no histological signs of atrophy were found during the first colonoscopy. Surprisingly, the second and third colonoscopy revealed a region of advanced segmental mucosal atrophy in the cecum with the mucosal height normalizing toward the transverse colon. This pattern of atrophy was inversely related to the pattern of sub-epithelial collagen deposition, which increased toward the rectum.</p> <p>Conclusion</p> <p>If no chance occurrence, our observation supports the idea that additional factors, probably luminal in nature, may be co-responsible for the mucosal atrophy in this case. Thus, mucosal atrophy in the proximal colon appears to be a new candidate among the growing list of rare complications associated with long standing CC.</p

A Bioelectrochemical Approach to Characterize Extracellular Electron Transfer by Synechocystis sp. PCC6803

Biophotovoltaic devices employ photosynthetic organisms at the anode of a microbial fuel cell to generate electrical power. Although a range of cyanobacteria and algae have been shown to generate photocurrent in devices of a multitude of architectures, mechanistic understanding of extracellular electron transfer by phototrophs remains minimal. Here we describe a mediatorless bioelectrochemical device to measure the electrogenic output of a planktonically grown cyanobacterium, Synechocystis sp. PCC6803. Light dependent production of current is measured, and its magnitude is shown to scale with microbial cell concentration and light intensity. Bioelectrochemical characterization of a Synechocystis mutant lacking Photosystem II demonstrates conclusively that production of the majority of photocurrent requires a functional water splitting aparatus and electrons are likely ultimately derived from water. This shows the potential of the device to rapidly and quantitatively characterize photocurrent production by genetically modified strains, an approach that can be used in future studies to delineate the mechanisms of cyanobacterial extracellular electron transport

Establishment of the first International Standard for human anti-typhoid capsular Vi polysaccharide IgG

Vi capsular polysaccharide (Vi) conjugate vaccines, which can prevent typhoid in infants and young children, are being developed. Comparative immunogenicity studies are facilitated by an International Standard (IS) for human anti-Vi IgG. 16/138, a pool of sera from volunteers which received either Vi conjugate vaccine or plain Vi vaccine, was assessed as an IS alongside U.S. reference reagent Vi-IgGR1, 2011. Samples were tested in a commercial ELISA (n = 7), a standardised ELISA based on biotinylated Vi (n = 7) and in-house ELISAs (n = 7). Valid estimates were obtained for the potency of all samples in the commercial ELISA, and the commutability of 16/138 and Vi-IgGR1, 2011 was evident for the commercial ELISA and in-house ELISAs based on a coating of Vi and protein. The WHO Expert Committee on Biological Standardization established 16/138 as the first IS for anti-Vi IgG with 100 IU per ampoule and assigned 163 IU per vial of Vi-IgGR1, 2011

Predictors of Ips confusus Outbreaks During a Record Drought in Southwestern USA: Implications for Monitoring and Management

In many ecosystems the effects of disturbance can be cryptic and disturbance may vary in subtle spatiotemporal ways. For instance, we know that bark beetle outbreaks are more frequent in temperate forests during droughts; however, we have little idea about why they occur in some locations and not others. Understanding biotic and abiotic factors promoting bark beetle outbreaks can be critical to predicting and responding to pest outbreaks. Here we address the environmental factors which are associated with Ips confusus outbreaks during the 2002 widespread drought within the distribution range of pinyon pine woodlands in Arizona. We used univariate statistics to test if whether tree characteristics, other herbivores, stand properties, soil type, wind, and topography were associated with I. confusus outbreak, and logistic regression to create a predictive model for the outbreaks. We found that I. confusus attacks occur in low elevation stands on steeper slopes, where favorable winds for I. confusus dispersion occur. I. confusus select larger trees, in high density stands with understory shrubs that exhibit phenotypic traits characteristic of resistance to stem-boring moths. The model was highly accurate, and explained 95% of the variability in occurrence (98% of the absences and 95% of the presences). Accurate prediction of the impacts of disturbance allow us to anticipate, minimize or mitigate for and eventually counteract its effects, especially those affecting diversity and ecosystem function. Identification of outbreak risk areas can guide regional and national management towards the reduction of infestation risk and enhancing conservation of pinyon-juniper woodlands