1,575 research outputs found

    A Novel Visual Word Co-occurrence Model for Person Re-identification

    Full text link
    Person re-identification aims to maintain the identity of an individual in diverse locations through different non-overlapping camera views. The problem is fundamentally challenging due to appearance variations resulting from differing poses, illumination and configurations of camera views. To deal with these difficulties, we propose a novel visual word co-occurrence model. We first map each pixel of an image to a visual word using a codebook, which is learned in an unsupervised manner. The appearance transformation between camera views is encoded by a co-occurrence matrix of visual word joint distributions in probe and gallery images. Our appearance model naturally accounts for spatial similarities and variations caused by pose, illumination & configuration change across camera views. Linear SVMs are then trained as classifiers using these co-occurrence descriptors. On the VIPeR and CUHK Campus benchmark datasets, our method achieves 83.86% and 85.49% at rank-15 on the Cumulative Match Characteristic (CMC) curves, and beats the state-of-the-art results by 10.44% and 22.27%.Comment: Accepted at ECCV Workshop on Visual Surveillance and Re-Identification, 201

    Calcite-accumulating large sulfur bacteria of the genus Achromatium in Sippewissett Salt Marsh

    Get PDF
    Large sulfur bacteria of the genus Achromatium are exceptional among Bacteria and Archaea as they can accumulate high amounts of internal calcite. Although known for more than 100 years, they remain uncultured, and only freshwater populations have been studied so far. Here we investigate a marine population of calcite-accumulating bacteria that is primarily found at the sediment surface of tide pools in a salt marsh, where high sulfide concentrations meet oversaturated oxygen concentrations during the day. Dynamic sulfur cycling by phototrophic sulfide-oxidizing and heterotrophic sulfate-reducing bacteria co-occurring in these sediments creates a highly sulfidic environment that we propose induces behavioral differences in the Achromatium population compared with reported migration patterns in a low-sulfide environment. Fluctuating intracellular calcium/sulfur ratios at different depths and times of day indicate a biochemical reaction of the salt marsh Achromatium to diurnal changes in sedimentary redox conditions. We correlate this calcite dynamic with new evidence regarding its formation/mobilization and suggest general implications as well as a possible biological function of calcite accumulation in large bacteria in the sediment environment that is governed by gradients. Finally, we propose a new taxonomic classification of the salt marsh Achromatium based on their adaptation to a significantly different habitat than their freshwater relatives, as indicated by their differential behavior as well as phylogenetic distance on 16S ribosomal RNA gene level. In future studies, whole-genome characterization and additional ecophysiological factors could further support the distinctive position of salt marsh Achromatium

    ‘Do i care?’ young adults' recalled experiences of early adolescent overweight and obesity: a qualitative study

    Get PDF
    <p>Objective: Individual behaviour change to reduce obesity requires awareness of, and concern about, weight. This paper therefore describes how young adults, known to have been overweight or obese during early adolescence, recalled early adolescent weight-related awareness and concerns. Associations between recalled concerns and weight-, health- and peer-related survey responses collected during adolescence are also examined.</p> <p>Design: Qualitative semi-structured interviews with young adults; data compared with responses to self-report questionnaires obtained in adolescence.</p> <p>Participants: A total of 35 participants, purposively sub-sampled at age 24 from a longitudinal study of a school year cohort, previously surveyed at ages 11, 13 and 15. Physical measures during previous surveys allowed identification of participants with a body mass index (BMI) indicative of overweight or obesity (based on British 1990 growth reference) during early adolescence. Overall, 26 had been obese, of whom 11 had BMI99.6th centile, whereas 9 had been overweight (BMI=95th–97.9th centile).</p> <p>Measures: Qualitative interview responses describing teenage life, with prompts for school-, social- and health-related concerns. Early adolescent self-report questionnaire data on weight-worries, self-esteem, friends and victimisation (closed questions).</p> <p>Results: Most, but not all recalled having been aware of their overweight. None referred to themselves as having been obese. None recalled weight-related health worries. Recollection of early adolescent obesity varied from major concerns impacting on much of an individual's life to almost no concern, with little relation to actual severity of overweight. Recalled concerns were not clearly patterned by gender, but young adult males recalling concerns had previously reported more worries about weight, lower self-esteem, fewer friends and more victimisation in early adolescence; no such pattern was seen among females. Conclusion: The popular image of the unhappy overweight teenager was not borne out. Many obese adolescents, although well aware of their overweight recalled neither major dissatisfaction nor concern. Weight-reduction behaviours are unlikely in such circumstances.</p&gt

    The association of health literacy with adherence in older 2 adults, and its role in interventions: a systematic meta-review

    Get PDF
    Background: Low health literacy is a common problem among older adults. It is often suggested to be associated with poor adherence. This suggested association implies a need for effective adherence interventions in low health literate people. However, previous reviews show mixed results on the association between low health literacy and poor adherence. A systematic meta-review of systematic reviews was conducted to study the association between health literacy and adherence in adults above the age of 50. Evidence for the effectiveness of adherence interventions among adults in this older age group with low health literacy was also explored. Methods: Eight electronic databases (MEDLINE, ERIC, EMBASE, PsycINFO, CINAHL, DARE, the Cochrane Library, and Web of Knowledge) were searched using a variety of keywords regarding health literacy and adherence. Additionally, references of identified articles were checked. Systematic reviews were included if they assessed the association between health literacy and adherence or evaluated the effectiveness of interventions to improve adherence in adults with low health literacy. The AMSTAR tool was used to assess the quality of the included reviews. The selection procedure, data-extraction, and quality assessment were performed by two independent reviewers. Seventeen reviews were selected for inclusion. Results: Reviews varied widely in quality. Both reviews of high and low quality found only weak or mixed associations between health literacy and adherence among older adults. Reviews report on seven studies that assess the effectiveness of adherence interventions among low health literate older adults. The results suggest that some adherence interventions are effective for this group. The interventions described in the reviews focused mainly on education and on lowering the health literacy demands of adherence instructions. No conclusions could be drawn about which type of intervention could be most beneficial for this population. Conclusions: Evidence on the association between health literacy and adherence in older adults is relatively weak. Adherence interventions are potentially effective for the vulnerable population of older adults with low levels of health literacy, but the evidence on this topic is limited. Further research is needed on the association between health literacy and general health behavior, and on the effectiveness of interventions

    Assessing Internet addiction using the parsimonious Internet addiction components model - a preliminary study [forthcoming]

    Get PDF
    Internet usage has grown exponentially over the last decade. Research indicates that excessive Internet use can lead to symptoms associated with addiction. To date, assessment of potential Internet addiction has varied regarding populations studied and instruments used, making reliable prevalence estimations difficult. To overcome the present problems a preliminary study was conducted testing a parsimonious Internet addiction components model based on Griffiths’ addiction components (2005), including salience, mood modification, tolerance, withdrawal, conflict, and relapse. Two validated measures of Internet addiction were used (Compulsive Internet Use Scale [CIUS], Meerkerk et al., 2009, and Assessment for Internet and Computer Game Addiction Scale [AICA-S], Beutel et al., 2010) in two independent samples (ns = 3,105 and 2,257). The fit of the model was analysed using Confirmatory Factor Analysis. Results indicate that the Internet addiction components model fits the data in both samples well. The two sample/two instrument approach provides converging evidence concerning the degree to which the components model can organize the self-reported behavioural components of Internet addiction. Recommendations for future research include a more detailed assessment of tolerance as addiction component

    The fate of steroid estrogens: Partitioning during wastewater treatment and onto river sediments

    Get PDF
    This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2010 Springer Science+Business Media B.V.The partitioning of steroid estrogens in wastewater treatment and receiving waters is likely to influence their discharge to, and persistence in, the environment. This study investigated the partitioning behaviour of steroid estrogens in both laboratory and field studies. Partitioning onto activated sludge from laboratory-scale Husmann units was rapid with equilibrium achieved after 1 h. Sorption isotherms and Kd values decreased in the order 17α-ethinyl estradiol > 17α-estradiol > estrone > estriol without a sorption limit being achieved (1/n >1). Samples from a wastewater treatment works indicated no accumulation of steroid estrogens in solids from primary or secondary biological treatment, however, a range of steroid estrogens were identified in sediment samples from the River Thames. This would indicate that partitioning in the environment may play a role in the long-term fate of estrogens, with an indication that they will be recalcitrant in anaerobic conditions.EPSR

    Alcohol affects neuronal substrates of response inhibition but not of perceptual processing of stimuli signalling a stop response

    Get PDF
    Alcohol impairs inhibitory control, including the ability to terminate an initiated action. While there is increasing knowledge about neural mechanisms involved in response inhibition, the level at which alcohol impairs such mechanisms remains poorly understood. Thirty-nine healthy social drinkers received either 0.4g/kg or 0.8g/kg of alcohol, or placebo, and performed two variants of a Visual Stop-signal task during acquisition of functional magnetic resonance imaging (fMRI) data. The two task variants differed only in their instructions: in the classic variant (VSST), participants inhibited their response to a “Go-stimulus” when it was followed by a “Stop-stimulus”. In the control variant (VSST_C), participants responded to the “Go-stimulus” even if it was followed by a “Stop-stimulus”. Comparison of successful Stop-trials (Sstop)>Go, and unsuccessful Stop-trials (Ustop)>Sstop between the three beverage groups enabled the identification of alcohol effects on functional neural circuits supporting inhibitory behaviour and error processing. Alcohol impaired inhibitory control as measured by the Stop-signal reaction time, but did not affect other aspects of VSST performance, nor performance on the VSST_C. The low alcohol dose evoked changes in neural activity within prefrontal, temporal, occipital and motor cortices. The high alcohol dose evoked changes in activity in areas affected by the low dose but importantly induced changes in activity within subcortical centres including the globus pallidus and thalamus. Alcohol did not affect neural correlates of perceptual processing of infrequent cues, as revealed by conjunction analyses of VSST and VSST_C tasks. Alcohol ingestion compromises the inhibitory control of action by modulating cortical regions supporting attentional, sensorimotor and action-planning processes. At higher doses the impact of alcohol also extends to affect subcortical nodes of fronto-basal ganglia- thalamo-cortical motor circuits. In contrast, alcohol appears to have little impact on the early visual processing of infrequent perceptual cues. These observations clarify clinically-important effects of alcohol on behaviour

    Competing mortality in patients diagnosed with bladder cancer: evidence of undertreatment in the elderly and female patients

    Get PDF
    Background: Bladder cancer (BC) predominantly affects the elderly and is often the cause of death among patients with muscleinvasive disease. Clinicians lack quantitative estimates of competing mortality risks when considering treatments for BC. Our aim was to determine the bladder cancer-specific mortality (CSM) rate and other-cause mortality (OCM) rate for patients with newly diagnosed BC. Methods: Patients (n ÂŒ 3281) identified from a population-based cancer registry diagnosed between 1994 and 2009. Median follow-up was 48.15 months (IQ range 18.1–98.7). Competing risk analysis was performed within patient groups and outcomes compared using Gray’s test. Results: At 5 years after diagnosis, 1246 (40%) patients were dead: 617 (19%) from BC and 629 (19%) from other causes. The 5-year BC mortality rate varied between 1 and 59%, and OCM rate between 6 and 90%, depending primarily on the tumour type and patient age. Cancer-specific mortality was highest in the oldest patient groups. Few elderly patients received radical treatment for invasive cancer (52% vs 12% for patients o60 vs 480 years, respectively). Female patients with high-risk non-muscle-invasive BC had worse CSM than equivalent males (Gray’s Po0.01). Conclusion: Bladder CSM is highest among the elderly. Female patients with high-risk tumours are more likely to die of their disease compared with male patients. Clinicians should consider offering more aggressive treatment interventions among older patients

    Proof of concept of faecal egg nematode counting as a practical means of veterinary engagement with planned livestock health management in a lower income country

    Get PDF
    Abstract Background The wellbeing and livelihood of farmers in impoverished regions of the world is intrinsically linked to the health and welfare of their livestock; hence improved animal health is a pragmatic component of poverty alleviation. Prerequisite knowledge and understanding of the animal health challenges facing cattle keepers in Malawi is constrained by the lack of veterinary infrastructure, which inevitably accompanies under-resourced rural development in a poor country. Methods We collaborated with public and private paraveterinary services to locate 62 village Zebu calves and 60 dairy co-operative calves dispersed over a wide geographical area. All calves were visited twice about 2 to 3 weeks apart, when they were clinically examined and faecal samples were collected. The calves were treated with 7.5 mg/kg of a locally-available albendazole drench on the first visit, and pre- and post- treatment trichostrongyle and Toxocara faecal egg counts were performed using a modified McMaster method. Results Our clinical findings point towards a generally poor level of animal health, implying a role of ticks and tick-transmitted diseases in village calves and need for improvement in neonatal calf husbandry in the dairy co-operative holdings. High faecal trichostrongyle egg counts were not intuitive, based on our interpretation of the animal management information that was provided. This shows the need for better understanding of nematode parasite epidemiology within the context of local husbandry and environmental conditions. The albendazole anthelmintic was effective against Toxocara, while efficacy against trichostrongyle nematodes was poor in both village and dairy co-operative calves, demonstrating the need for further research to inform sustainable drug use. Conclusions Here we describe the potential value of faecal nematode egg counting as a platform for communicating with and gaining access to cattle keepers and their animals, respectively, in southern Malawi, with the aim of providing informative background knowledge and understanding that may aid in the establishment of effective veterinary services in an under-resourced community

    Spatial Distribution of Dominant Arboreal Ants in a Malagasy Coastal Rainforest: Gaps and Presence of an Invasive Species

    Get PDF
    We conducted a survey along three belt transects located at increasing distances from the coast to determine whether a non-random arboreal ant assemblage, such as an ant mosaic, exists in the rainforest on the Masoala Peninsula, Madagascar. In most tropical rainforests, very populous colonies of territorially dominant arboreal ant species defend absolute territories distributed in a mosaic pattern. Among the 29 ant species recorded, only nine had colonies large enough to be considered potentially territorially dominant; the remaining species had smaller colonies and were considered non-dominant. Nevertheless, the null-model analyses used to examine the spatial structure of their assemblages did not reveal the existence of an ant mosaic. Inland, up to 44% of the trees were devoid of dominant arboreal ants, something not reported in other studies. While two Crematogaster species were not associated with one another, Brachymyrmex cordemoyi was positively associated with Technomyrmex albipes, which is considered an invasive species—a non-indigenous species that has an adverse ecological effect on the habitats it invades. The latter two species and Crematogaster ranavalonae were mutually exclusive. On the other hand, all of the trees in the coastal transect and at least 4 km of coast were occupied by T. albipes, and were interconnected by columns of workers. Technomyrmex albipes workers collected from different trees did not attack each other during confrontation tests, indicating that this species has formed a supercolony along the coast. Yet interspecific aggressiveness did occur between T. albipes and Crematogaster ranavalonae, a native species which is likely territorially dominant based on our intraspecific confrontation tests. These results suggest that the Masoala rainforest is threatened by a potential invasion by T. albipes, and that the penetration of this species further inland might be facilitated by the low density of native, territorially dominant arboreal ants normally able to limit its progression
    • 

    corecore