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Influence of ambient humidity on the attachment ability of ladybird beetles (Coccinella septempunctata)
No full textMany insects possess adhesive foot pads, which enable them to scale smooth vertical surfaces. The function of these organs may be highly affected by environmental conditions. Ladybird beetles (Coccinellidae) possess dense tarsal soles of tenent setae, supplemented with an adhesive fluid. We studied the attachment ability of the seven-spotted ladybird beetle (Coccinella septempunctata) at different humidities by horizontal traction experiments. We found that both low (15%) and high (99%) relative humidities lead to a decrease of attachment ability. The significantly highest attachment forces were revealed at 60% humidity. This relationship was found both in female and male beetles, despite of a deviating structure of adhesive setae and a significant difference in forces between sexes. These findings demonstrate that not only dry adhesive setae are affected by ambient humidity, but also setae that stick due to the capillarity of an oily secretion.8 page(s
Practical approximate k nearest neighbor queries with location and query privacy
No full textIn mobile communication, spatial queries pose a serious threat to user location privacy because the location of a query may reveal sensitive information about the mobile user. In this paper, we study approximate k nearest neighbor (kNN) queries where the mobile user queries the location-based service (LBS) provider about approximate k nearest points of interest (POIs) on the basis of his current location. We propose a basic solution and a generic solution for the mobile user to preserve his location and query privacy in approximate kNN queries. The proposed solutions are mainly built on the Paillier public-key cryptosystem and can provide both location and query privacy. To preserve query privacy, our basic solution allows the mobile user to retrieve one type of POIs, for example, approximate k nearest car parks, without revealing to the LBS provider what type of points is retrieved. Our generic solution can be applied to multiple discrete type attributes of private location-based queries. Compared with existing solutions for kNN queries with location privacy, our solution is more efficient. Experiments have shown that our solution is practical for kNN queries.14 page(s
Letter to the Editor
No full textIn reviewing Melikyan et al., we discuss what we think are weaknesses in the case report. The authors did not report on known risk factors for cerebrovascular accident and vertebral artery dissection. Known symptoms that appear early in vertebral artery dissection were not reported or denied, specifically related to changes in the patient's pattern of neck pain. Causality was assumed when only a weak temporal relation was involved. Finally, the case report makes it appear that the manipulation was performed by someone other than a chiropractor but therefore erroneously uses chiropractic in the title.3 page(s
Art has a place : country as a teacher in the city
No full textCountry constitutes the very anchor of life for many Aboriginal and Torres Strait Islander people in Australia. It is central to Indigenous identities and history, and is a powerful signifier of overall health and well-being; yet, the significance of country to Indigenous people living in large urban localities such as Sydney, Australia, remains an enigma. Through the production of a series of three murals on a university campus, this project was designed to explore the significance of country for three Darug artists working alongside 90 pre-service teachers enrolled in teacher education. The authors were working with the notion that Aboriginal art comes from country and should stay on country; hence, the painting was directed by Darug artists because we were teaching and learning on Darug country. Our objective, though, was to explore through practice how country teaches in the city, and to produce new stories of coexistence. Narratives developed around terms of engagement and the relationships that developed through project partnerships.15 page(s
Differing trends in fall-related fracture and non-fracture injuries in older people with and without dementia
No full textObjectives: To explore the impact of dementia on the trends in fall-related fracture and non-fracture injuries for older people. Methods: Individuals aged ≥65years who were admitted to a NSW hospital for at least an over-night stay for a fall-related injury from 2003 to 2012 were identified. Age-standardised hospitalisation rates, length of stay, access to in-hospital rehabilitation, 30-day and 1-year mortality were examined. Annual percentage change (PAC) over time was calculated using negative binomial regression. Results: Of the 228,628 fall-related injury hospitalisations, 20.6% were for people with dementia. People with dementia were more likely to be admitted with a hip fracture, and less likely to be admitted with a fracture of the forearm/wrist, and received less in-hospital rehabilitation than people without dementia. Fall-related hip-fracture rates for people with dementia decreased by 4.2% (95%CI -5.6 to -2.7, p<0.001) per annum; there was no change over time for people without dementia (PAC-0.2%; 95%CI -0.8 to 0.5, p=0.643). Rates for other fractures decreased by 1.2% (95%CI -1.9 to -0.5, p<0.001) per annum in people with dementia, while rates increased by 2.2% (95%CI 1.9-2.5, p<0.001) for people without dementia. By contrast, non-fracture injuries including traumatic brain injury increased significantly for both people with and without dementia. Conclusion: Rates of fall-related fracture and non-fracture hospitalisations for people with dementia remain higher than for those without dementia. However, fall-related fracture hospitalisation rates have decreased for people with dementia, while there has not been a corresponding decrease in people without dementia.7 page(s
Downlink coverage analysis of two-tier heterogeneous networks with asynchronous slots
No full textUsing stochastic geometry, downlink (DL) coverage probability in slot-based two-tier heterogeneous cellular networks (HCNs) is studied. Two traffic patterns namely slotted-asynchronous and exponential-interarrival are introduced to capture user activity, and the DL coverage probability based on max-SINR association is derived. In contrast to many works, the transmission slots of base stations (BS) are not synchronous. This causes a packet transmitted in one slot to experience varying levels of interference during the time slot interval. The SINR statistical distribution during one slot is derived for both traffic patterns. The numerical results are presented to illustrate the analytical ones. The comparison between asynchronous and conventional synchronous HCNs is provided to illustrate the asynchronous effect on DL performance. It is shown that to meet high coverage requirements, synchronizing slots from different BSs help to boost the coverage performance. Furthermore, it is shown that densifying networks with low-power BSs improves coverage performance and the improvement is more pronounced at higher path-loss exponents.6 page(s
The Internet, cognitive enhancement, and the values of cognition
No full textThis paper has two distinct but related goals: (1) to identify some of the potential consequences of the Internet for our cognitive abilities and (2) to suggest an approach to evaluate these consequences. I begin by outlining the Google effect, which (allegedly) shows that when we know information is available online, we put less effort into storing that information in the brain. Some argue that this strategy is adaptive because it frees up internal resources which can then be used for other cognitive tasks, whereas others argue that this is maladaptive because it makes us less knowledgeable. I argue that the currently available empirical evidence in cognitive psychology does not support strong conclusions about the negative effects of the Internet on memory. Before we can make value-judgements about the cognitive effects of the Internet, we need more robust and ecologically-valid evidence. Having sketched a more nuanced picture of the Google effect, I then argue that the value of our cognitive abilities is in part intrinsic and in part instrumental, that is, they are both valuable in themselves and determined by the socio-cultural context in which these cognitive abilities are utilised. Focussing on instrumental value, I argue that, in an information society such as ours, having the skills to efficiently navigate, evaluate, compare, and synthesize online information are (under most circumstances) more valuable than having a lot of facts stored in biological memory. This is so, partly because using the Internet as an external memory system has overall benefits for education, navigation, journalism, and academic scholarship.19 page(s
Oral vocabulary knowledge and orthographic learning
No full textTheoretical thesis."Department of Cognitive Science , ARC Centre of Excellence in Cognition and its Disorders, Reading Research Group, Faculty of Human Sciences, Macquarie University, Sydney, Australia' -- title page.Bibliography: pages 87-96.Chapter 1. Thesis overview -- Chapter 2. Oral vocabulary and reading acquisition : a literature review -- Chapter 3. Orthographic learning commences before written words are seen : evidence from eye movements -- Chapter 4. General discussion.Children’s reading evolves from the slow and effortful process of using letter-to sound correspondences during word identification to rapid and skilled whole word recognition - a process referred to as orthographic learning. The question of how this is achieved remains open. This thesis explores the role of vocabulary knowledge in the processof orthographic learning and tests a possible mechanism for its influence. It is presented in two parts.Part One is a broad literature review that outlines what is currently known about the relationship between vocabulary knowledge and orthographic learning. Possible mechanisms via which vocabulary might exert an effect on orthographic learning are discussed, and are linked back to theoretical accounts that differ with respect to the proposed timing of the influence. Some posit an effect that begins at the time a word is seen in print, such as the self teachinghypothesis of Share (1995) and the lexical quality hypothesis of Perfetti (1992). Another – the orthographic recoding hypothesis – predicts that the effect may begin prior to any visual exposure (McKague, Davis, Pratt & Johnston, 2008). Topics relevant to how the proposed mechanisms might be understood and tested are then discussed.Part Two presents an empirical study which draws on the literature review to propose and test three hypotheses: first, that the partial knowledge engendered by oral familiarity with a word should confer an online processing advantage when children’s eye movements are monitored during reading; second, that words with predictable spellings based on their phonology should enjoy a processing advantage relative to words with unpredictable spellings; and finally, that the presence of a word in a child’s oral vocabulary, together with their knowledge of phoneme-grapheme mappings, allows them to form an orthographic “skeleton” of that word before seeing it in print. The principal findings from this study supported all three hypotheses, and are consistent with the position that orthographic learning can commence prior to visual exposure. Implications for theories of orthographic learning .Mode of access: World wide web1 online resource (xii, 105 pages) diagrams, graphs, table
“In the eye of the typhoon”: aspirations of Buddhists and Catholics in turbulent Hong Kong
No full textTheoretical thesis.Bibliography: pages 217-228.Introduction -- Chapter 1. Studying religion in a Chinese context -- Chapter 2. Tradition, universalism and the aspiration to belong -- Chapter 3. Accountability and socio-economic aspirations -- Chapter 4. Salvation and rights to the city -- Chapter 5. Conclusion.This thesis wishes to contribute to the current scholarly debate on urban religion. This debate focuses predominantly on the visibility and materiality of religious practices and symbols in the urban environment; on the effect of migration (both rural-to-urban and transnational) on the religious landscape of the city; and on religion in cities in the ‘secularised’ West. My research aims to correct some of these biases by shedding light on the ways religion features in an Asian urban setting by residents in not-always public and/or visible ways. I argue that life in cities is not only shaped by religious practices and symbols, but equally by religious orientations, which provide a lens through which residents see and evaluate the complex and at times unsettling urban environment. To that end, I investigate the experiences of Hong Kong middle class Buddhists (primarily Theravāda Buddhists) and Catholics concerning tensions between the Hong Kong Special Administrative Region (HKSAR) and the People’s Republic of China (PRC) post-1997 Handover. These tensions culminated in the so-called Umbrella Movement, during which an estimated 1.2 million people occupied the streets of urban Hong Kong from late September to mid-December 2014.The thesis takes its point of departure in the realisation that there is antagonism between Mainland China and Hong Kong. Fears regarding this antagonism are especially expressed by members of Hong Kong’s middle class, who see their aspirations threatened and who describe their lives to be situated in political and socio-economic turbulence. This particular turbulence inscribes itself in middle class Buddhist and Catholic orientations. At the same time, these orientations shape their attitudes towards the changes and challenges they face.In the three main chapters that constitute this thesis (which follow a brief exploration of the position of Buddhism and Catholicism in historical and contemporary Hong Kong) I investigate how specific urban circumstances and religious orientations mutually influence each other, shaping people’s day-to-day city lives. I do this by exploring three themes. The first theme deals with how and why my informants emphasise tradition and universalism as the stable foundations of their religions. These foundations provide them with an anchor in the uncertain political environment in which they live. The second theme regards personal accountability as a central tenet in my informants’ religious beliefs, appointing their role and position in their religion and in the world. The specific notion of religious accountability shapes the way in which my informants negotiate the threat Mainland China poses to their socio-economic aspirations. Regarding the third theme, I investigate how, by trying to (re)gain the rights to the city during the Umbrella Movement, my interlocutors highlight their religious aspirations of salvation as a possible goal in the here and now. In all these themes, global, local, religious, and non-religious factors combine to give shape to life in the city of Hong Kong.Mode of access: World wide web1 online resource (xvi, 230 pages) colour illustration