The influence of feature-based information in the age processing of unfamiliar faces

The influence of the internal features (eyes, nose, and mouth) in the age processing of unfamiliar faces was examined. Younger and older versions of the faces of six individuals (covering three different age ranges, from infancy to maturity) were used as donor stimuli. For each individual in turn, the effects on age estimates of placing older features in the younger face version (or vice versa) were investigated. Age estimates were heavily influenced by the age of the internal facial features. Experiment 2 replicated these effects with a larger number of faces within a narrower age range (after growth is complete and before major skin changes have occurred). Taken together, these two experiments show that the internal facial features may be influential in conveying age information to the perceiver. However, the mechanisms by which features exert their influence remain difficult to determine: although age estimates might be based on local information from the features themselves, an alternative possibility is that featural changes indirectly influence age estimates by altering the global three-dimensional shape of the head

Evaluation of Automatic Video Captioning Using Direct Assessment

We present Direct Assessment, a method for manually assessing the quality of automatically-generated captions for video. Evaluating the accuracy of video captions is particularly difficult because for any given video clip there is no definitive ground truth or correct answer against which to measure. Automatic metrics for comparing automatic video captions against a manual caption such as BLEU and METEOR, drawn from techniques used in evaluating machine translation, were used in the TRECVid video captioning task in 2016 but these are shown to have weaknesses. The work presented here brings human assessment into the evaluation by crowdsourcing how well a caption describes a video. We automatically degrade the quality of some sample captions which are assessed manually and from this we are able to rate the quality of the human assessors, a factor we take into account in the evaluation. Using data from the TRECVid video-to-text task in 2016, we show how our direct assessment method is replicable and robust and should scale to where there many caption-generation techniques to be evaluated.Comment: 26 pages, 8 figure

Recognising the ageing face: the role of age in face processing

The effects of age-induced changes on face recognition were investigated as a means of exploring the role of age in the encoding of new facial memories. The ability of participants to recognise each of six previously learnt faces was tested with versions which were either identical to the learnt faces, the same age (but different in pose and expression), or younger or older in age. Participants were able to cope well with facial changes induced by ageing: their performance with older, but not younger, versions was comparable to that with faces which differed only in pose and expression. Since the large majority of different age versions were recognised successfully, it can be concluded that the process of recognition does not require an exact match in age characteristics between the stored representation of a face and the face currently in view. As the age-related changes explored here were those that occur during the period of growth, this in turn implies that the underlying structural physical properties of the face are (in addition to pose and facial expression) invariant to a certain extent

Factors influencing the accuracy of age-estimates of unfamiliar faces

Factors affecting the accuracy with which adults could assess the age of unfamiliar male faces aged between 5 and 70 years were examined. In the first experiment twenty-five 'young' adult subjects, aged 16-25, and twenty-five 'old' adults, aged 51-60, were used. Each subject saw five versions of three different faces: these consisted of an original version of each face and four manipulated versions of it. The manipulations consisted of mirror reversal, pseudo-cardioidal strain, thresholding, and elimination of all but the internal features of the face. The second experiment was similar except that a between-subjects design was used: each subject saw three faces for each age category of target face, but was exposed to only a single type of manipulation (plus a set of 'original' faces which were identical for all groups, so that the comparability of the different groups in age estimation could be checked). Results from both experiments were similar. Age estimates for unmanipulated 'original' faces were highly accurate, although subjects were most accurate with target faces that were within their own age range. Results for the manipulated faces implied that the importance of cardioidal strain as a necessary and sufficient cue to age may have been overestimated in previous reports: subjects' age estimates were accurate when cardioidal strain was absent from the stimulus, and poor when cardioidal strain was the only cue available

Present and future potential of plant-derived products to control arthropods of veterinary and medical significance

The use of synthetic pesticides and repellents to target pests of veterinary and medical significance is becoming increasingly problematic. One alternative approach employs the bioactive attributes of plant-derived products (PDPs). These are particularly attractive on the grounds of low mammalian toxicity, short environmental persistence and complex chemistries that should limit development of pest resistance against them. Several pesticides and repellents based on PDPs are already available, and in some cases widely utilised, in modern pest management. Many more have a long history of traditional use in poorer areas of the globe where access to synthetic pesticides is often limited. Preliminary studies support that PDPs could be more widely used to target numerous medical and veterinary pests, with modes of action often specific to invertebrates. Though their current and future potential appears significant, development and deployment of PDPs to target veterinary and medical pests is not without issue. Variable efficacy is widely recognised as a restraint to PDPs for pest control. Identifying and developing natural bioactive PDP components in place of chemically less-stable raw or 'whole’ products seems to be the most popular solution to this problem. A limited residual activity, often due to photosensitivity or high volatility, is a further drawback in some cases (though potentially advantageous in others). Nevertheless, encapsulation technologies and other slow-release mechanisms offer strong potential to improve residual activity where needed. The current review provides a summary of existing use and future potential of PDPs against ectoparasites of veterinary and medical significance. Four main types of PDP are considered (pyrethrum, neem, essential oils and plant extracts) for their pesticidal, growth regulating and repellent or deterrent properties. An overview of existing use and research for each is provided, with direction to more extensive reviews given in many sections. Sections to highlight potential issues, modes of action and emerging and future potential are also included

Comparison of methods for numerical calculation of continuum damping

Continuum resonance damping is an important factor in determining the stability of certain global modes in fusion plasmas. A number of analytic and numerical approaches have been developed to compute this damping, particularly in the case of the toroidicity-induced shear Alfv\'en eigenmode. This paper compares results obtained using an analytical perturbative approach with those found using resistive and complex contour numerical approaches. It is found that the perturbative method does not provide accurate agreement with reliable numerical methods for the range of parameters examined. This discrepancy exists even in the limit where damping approaches zero. When the perturbative technique is implemented using a standard finite element method, the damping estimate fails to converge with radial grid resolution. The finite elements used cannot accurately represent the eigenmode in the region of the continuum resonance, regardless of the number of radial grid points used.Comment: 19 pages, 9 figure

Biomediation of Turbulence and Suspended Sediment Characteristics in Marsh Surface Flows - The Influence of Spartina anglica

Laboratory experimentation in a large aimular flume (radius 3 m, channel width and water depth 0.4 m) has been conducted using a geometrically and dynamically similar Spariina anglica mimic (canopy height 0.21 m, stem density 1000 stems m~^) to investigate the influence of submerged Spartina on hydrodynamics under unidirectional currents {Uh = 0.2 m s~*) and the impact upon the dynamics of suspended cohesive sediments near the bed within the canopy. The vertical distribution of canopy biomass strongly influences vertical profiles of time-averaged velocity and turbulent quantities. An inflected velocity profile is observed in the region 0.79 < z/h < 0.9 which generates shear, T K E and Reynolds Stress peaks within vicinity of the canopy top. In this region T K E peaks at 15 times the levels observed in un-vegetated experiments. Flows at the canopy top are strongly intermittent with extremely efficient downward momentum transfer, uf] and ufz (stream-wise and vertical zero-mean fluctuating velocity) skewness are 0.5 and -0.5 indicating the presence of intermittent downward penetrating gusts. Near the bed (0 < z/h < 0.3) mean flow velocities are reduced by 88 - 90% in comparison to un-vegetated flows but turbulence intensities are strongly augmented by wake shedding from vegetative elements. TKE in this region is approximately equal to that in un-vegetated flows. Novel field observations in a low energ>', estuarine fringing marsh site on the Tavy Estuary, UK, with a vertical array of synchronous velocimeters and optical backscatter sensors exhibit low velocities (<0.6 ra s"*) and suspension concentrations (<100 mg L"*) in agreement with laboratory simulations. While field observations of near bed flows exhibit similarity to those measured in the laboratory, magnitudes of time-averaged flow throughout the water column are so small that the velocity profile appears constant over depth. Superimposed upon the low field velocities are small wind generated waves ( < 0.05 m in height and with periods < 3 s) which have a considerable impact on flow energy and stress estimates, but crucially, cannot be replicated in the laboratory experiments. Dissipation rates within the laboratory canopy are 70-200x10"'* m~^s"^ giving reduced Kohnogorov length scales of 0.04 - 0.14 mm. Field values for dissipation are generally of similar magnitude but peak at up to 600 X10"** m~^s~^. Kolmogorov length scales are consequently 0.06 - 2.6 mm. Using natural intertidal mud, suspension concentrations of 100-200 mg L~* have been sheared through the mimic canopy. Observations from a vertical array of miniaturised OBS sensors suggests sediments are maintained in suspension twice as long, under constant unidirectional currents, compared to un-vegetated flows. In the field initial concentrations of 100 mg L~* quickly decay to background levels of <20 mg L"* indicating the rapid setthng of material from suspension. Use of a novel digital in-line holographic particle iinaging system and the development of a particle tracking methodology has enabled the high resolution observation of both sample size and settling velocities of suspended cohesive particles. Laboratory observations of sample averaged size (74.5 - 111.7 mm) and settling rates (0.35 - 1 mm s~*) are in agreement with published estimates and the limited observational data that exists for settling rates in marsh systems. Settling velocities estimated in the field at 0.1 - 0.8 mm s~^. Significantly larger and fast settling aggregates have been observed than previously recorded. In the narrow range of experimental suspension concentrations and shear stresses utilised in the present experiments, significant diff^erences in particle size and settling velocity between vegetated and un-vegetated flows cannot be identified. Contrasting flux estimates using sample averaged settling rates and concentrations with full spectral estimates derived from the holographic particle imager indicate an error in the former fluxes of, on average, 62%. The range of settling rates observed during the pr^ent study raises questions regarding the accurate representation of marsh surface settling fluxes in numerical simulations. Large magnitude flux errors may have significant implications for accurate accretion rates in numerical models of marsh sedimentation

Identifying individuals at-risk of developing oesophageal adenocarcinoma through symptom, risk factor and salivary biomarker analysis

Background: Oesophageal adenocarcinoma (OAC) carries a grave prognosis. Existing early detection strategies are flawed predominately because of reliance upon symptoms known to occur late when the disease is often incurable. Detection of individuals with Barrett’s Oesophagus (BO), a known pre-malignant condition, is problematic and the vast majority will not develop OAC. Aim: To explore novel methods of identifying patients with or at risk of OAC through machine learning (ML) techniques and biomarker identification. Materials and Methods: Initial work utilised novel ML on two existing patient symptom and risk factor questionnaire datasets. Additionally, targeted expression analysis was performed to establish whether transcriptomic biomarkers were present in blood and saliva of affected patients. Optimal RNA extraction techniques and saliva collection strategies for sufficient quality and quantity RNA were determined. Whole mRNA sequencing was performed on patient salivary RNA to identify biomarkers for future assessment. Epigenetic analysis was performed on salivary DNA to identify biomarkers. ML techniques analysed these data to derive a risk prediction tool. Results: ML techniques on questionnaire data produced satisfactory sensitivity (90%), but accuracy not appropriate for population screening (AUC 0.77). Blood and saliva extraction and collection methods were established and samples found to contain biomarkers. Targeted transcriptomic expression analysis demonstrated 12 / 22 tested genes were significantly aberrantly expressed in patients. 5 genes, combined with 6 questionnaire data-points, identified those with or at risk of OAC 93% sensitivity, AUC 0.88. Whole mRNA sequencing identified a further 134 genes implicated in OAC pathogenesis requiring future testing. Epigenetic analysis found 25 differentially methylated regions, when combined, identified those with or at risk of OAC to 99.9% accuracy. 5 Conclusion: Utilisation of salivary biomarkers is a potentially effective means to identify individuals with or at risk of OAC. Further work exploring transcriptomic and epigenetic data established in this thesis should be performed

A Characterization Of The Fast Pyrolysis Of Cellulose And Wood Biomass

The science of biomass fast pyrolysis is relatively young and incomplete. To date, there has been no systematic attempt to define fast pyrolysis in terms of chemistry, product distribution, kinetics, heat transfer requirements, and requisite process conditions. Neither has there been any experimental work which tracks the reaction progress as a function of both temperature and residence time. Furthermore, the literature provides a fragmented and often contradictory view of the nature of fast pyrolysis.;This thesis provides a coherent picture of the fast pyrolysis of cellulose and wood via an extensive literature review and systematic research. The literature review is an essential element of the thesis. It is not an uncritical summary, but is an interpretive integration of published knowledge. As such, it provides a comprehensive structure for the characterization of biomass fast pyrolysis.;The literature review suggests that fast pyrolysis reactions consist of biomass activation followed by primary fragmentation and secondary vapour-phase cracking; the secondary cracking reactions are the focus of the thesis experimental work. This work was carried out predominantly in the Ultrapyrolysis plant at the University of Western Ontario, and to a lesser degree in the RTP plant at Ensyn Technologies Inc.;Both reactor systems provide extremely rapid heat transfer to biomass combined with precise control of short residence times. In order to prove the integrity and reliability of the hardware, initial work involved the rapid pyrolysis of a model compound (ethane) and a comparison of the use of both gaseous and solid particulate heat transfer media. The cornerstone work involved the systematic characterization of the product distribution of secondary cracking reactions as a function of temperature and residence time. The ranges of temperatures and residence times under investigation were 650 to 900{dollar}\sp\circ{dollar}C and 30 ms to 1 s, respectively. The data from this work was used to generate rate equations for the secondary reactions of cellulose and wood fast pyrolysis. Finally, a cooperative study was conducted with the University of Waterloo to compare cellulose fast pyrolysis results from two independent reactor systems. The joint study exhibited excellent agreement and congruity over a broad range of pyrolysis temperatures