Succinct Representations of Dynamic Strings

The rank and select operations over a string of length n from an alphabet of size $\sigma$ have been used widely in the design of succinct data structures. In many applications, the string itself need be maintained dynamically, allowing characters of the string to be inserted and deleted. Under the word RAM model with word size $w=\Omega(\lg n)$, we design a succinct representation of dynamic strings using $nH_0 + o(n)\lg\sigma + O(w)$ bits to support rank, select, insert and delete in $O(\frac{\lg n}{\lg\lg n}(\frac{\lg \sigma}{\lg\lg n}+1))$ time. When the alphabet size is small, i.e. when \sigma = O(\polylog (n)), including the case in which the string is a bit vector, these operations are supported in $O(\frac{\lg n}{\lg\lg n})$ time. Our data structures are more efficient than previous results on the same problem, and we have applied them to improve results on the design and construction of space-efficient text indexes

Lived experience of gay men caring for others with HIV/AIDS : living, loving and dying in the era of HIV/AIDS

This thesis explored gay male carers’ experience of caring for their partner, brother or friend who had HIV/AIDS. Through using phenomenological methodology (van Manen, 1990), the day-to-day caring experiences were uncovered. The data gathered were then analysed through a nursing ‘lens’, with the concept of stigma as an anchoring point. The dual stigmas of homophobia and AIDS phobia impacted on the daily lives of these men as they cared for their loved one. The research identified six themes. These were: 1) the relationship; 2) coping with HIV and AIDS; 3) the corporal impact of HIV/AIDS; 4) experiences of carers including the absence of others; 5) living daily with the virus: Demands of people living with HIV/AIDS (PLWHA); and 6) saying goodbye, but wanting to keep the memory alive. The caring these men undertook, for which they were frequently unprepared, was intensive and complex, but because of their commitment and love they battled on. Because of a sense of shame associated with AIDS phobia on the part of the PLWHA, the carer often had to undertake this care in isolation, without support from family, friends or home health care agencies. The carers struggled with not only the demands of day-to-day care, but also with non-acceptance from family, both of the nature of the relationship with their partner and of their homosexuality. Family members were forced, often with great difficulty, to acknowledge the close commitment the men had to each other. Recognition that one had a terminal disease, HIV/AIDS was also required. The fear of potential transmission was high among carers, friends and family members. Notably, there was an absence of blame on the part of the carer towards his partner for contracting HIV/AIDS. The physical decline and marking of the body further stigmatised the PLWHA, which added to carers’ burdens. They endeavoured to minimise the physical decline in their partner, so he could continue to pass as healthy, and attempted to make the day-to-day living as normal as possible. The methods of combating weight loss and opportunistic infections meant frequent medical appointments, complex intensive medical procedures and help with personal care, which was undertaken at home largely without support from health care staff. Carers frequently struggled also with their partner’s denial of being ill. One strategy all carers used was to escape with their partners from their everyday life in Melbourne and attempt metaphorically to leave the HIV/AIDS behind; this was a time when they could rekindle their life together as it was before HIV/AIDS came into their lives. Some carers chose to holiday without their partner, to give themselves a break from the day-to-day caring, while others planned and took holidays with their partner. The decline of the health in the PLWHA meant that family members had to recognise and accept both the nature of the relationship and the presence of the disease. This recognition and acceptance often came only when the partner was very ill, even at the point of dying. Carers and their partners discussed the potential use of euthanasia, as a means of ending the final phase of life with some dignity. One carer and his partner used euthanasia, despite its illegal status. The main concern for all carers was providing comfort and a reduction in the pain associated with HIV/AIDS for the partner. The widespread grief associated with HIV/AIDS was evident amongst these carers. All had known other gay men who had died, some carers own partner had died, or was about to die. There was an overwhelming sense of grief, which at times was repressed as a means of coping day-to-day. All carers felt it was important and necessary to remember those lost to HIV/AIDS through the various public memorials, as they did not want their partner to be just another faceless person lost to this disease. This phenomenological study of carers’ experience highlights the need for health care workers to be aware of the differing strategies that gay men use to cope with HIV/AIDS. While it may seem that the carers are coping with care of their partner, the outer façade is not always an accurate portrayal of the true situation. Health care workers should enquire as to the assistance these carers need from health care services in order to continue to care for their loved one. Such assistance can be the simple recognition of the partner and acceptance of them as part of the PLWHA’s network; this inclusion and acceptance is half the battle

Dynamic Data Structures for Document Collections and Graphs

In the dynamic indexing problem, we must maintain a changing collection of text documents so that we can efficiently support insertions, deletions, and pattern matching queries. We are especially interested in developing efficient data structures that store and query the documents in compressed form. All previous compressed solutions to this problem rely on answering rank and select queries on a dynamic sequence of symbols. Because of the lower bound in [Fredman and Saks, 1989], answering rank queries presents a bottleneck in compressed dynamic indexing. In this paper we show how this lower bound can be circumvented using our new framework. We demonstrate that the gap between static and dynamic variants of the indexing problem can be almost closed. Our method is based on a novel framework for adding dynamism to static compressed data structures. Our framework also applies more generally to dynamizing other problems. We show, for example, how our framework can be applied to develop compressed representations of dynamic graphs and binary relations

The family under the microscope: an experiment testing economic models of household choice.

We devise and execute three experiments to test key features of models of household decision-making. Using established couples (married and unmarried) we test income pooling, unanimity and Pareto efficiency. Subjects make choices individually and jointly and are asked to make predictions about their partner’s choices. Unanimity is rejected. Income pooling is not rejected in joint choice but has less explanatory power in individual choice. In direct tests both sexes do not pool income completely, but in econometric tests across all tasks, women place an equal weight on payoffs but men discount their partner’s payoffs by between 15 and 20%. We find that transparency has little impact on deviations from income pooling or indeed on behaviour generally. Many joint choices deviate from the Pareto principle in a systematic manner suggesting that choices made as a couple are more risk averse than individual decisions.experiment; household; unitary; income pooling; Pareto; family

An O(1) Solution to the Prefix Sum Problem on a Specialized Memory Architecture

In this paper we study the Prefix Sum problem introduced by Fredman. We show that it is possible to perform both update and retrieval in O(1) time simultaneously under a memory model in which individual bits may be shared by several words. We also show that two variants (generalizations) of the problem can be solved optimally in $\Theta(\lg N)$ time under the comparison based model of computation.Comment: 12 page

Fully integrated digital microfluidics platform for automated immunoassay; a versatile tool for rapid, specific detection of a wide range of pathogens

© 2018 Elsevier Ltd. All rights reserved. This manuscript is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Licence http://creativecommons.org/licenses/by-nc-nd/4.0/.With the tangible threat posed by the release of chemical and biological warfare (CBW) agents, detection of airborne pathogens is a critical military and security concern. Recent air sampling techniques developed for biocollection take advantage of Electrowetting on Dielectric (EWOD) to recover material, producing highly concentrated droplet samples. Bespoke EWOD-based digital microfluidics platforms are very well suited to take full advantage of the microlitre concentrated droplet resulting from this recovery process. In this paper we present a free-standing, fully automated DMF platform for immunoassay. Using this system, we demonstrate the automated detection of four classes of CBW agent simulant biomolecules and organisms each representing credible threat agents. Taking advantage of the full magnetic separation process with antibody-bound microbeads, rapid and complete separation of specific target antigen can be achieved with minimal washing steps allowing for very rapid detection. Here, we report clear detection of four categories of antigens achieved with assay completion times of between six and ten minutes. Detection of HSA, Bacillus atrophaeus (BG spores), MS2 bacteriophage and Escherichia coli are demonstrated with estimated limit of detection of respectively 30 ng ml -1, 4 × 10 4 cfu ml -1, 10 6 pfu ml -1 and 2 × 10 7 cfu ml -1. The fully-integrated portable platform described in this paper is highly compatible with the next generation of electrowetting-coupled air samplers and thus shows strong potential toward future in-field deployable biodetection systems and could have key implication in life-changing sectors such as healthcare, environment or food security.Peer reviewe