Fluorescent optical fibre chemosensor for the detection of mercury

This work aims to develop a stable, compact and portable fibre optic sensing system which is capable of real time detection of the mercury ion (II), Hg2+. A novel fluorescent polymeric material for Hg2+ detection, based on a coumarin derivative (acting as the fluorophore) and an azathia crown ether moiety (acting as the mercury ion receptor), has been designed and synthesized. The material was covalently attached to the distal end of an optical fibre and exhibited a significant increase in fluorescence intensity in response to Hg2+ in the μM concentration range via a photoinduced electron transfer (PET) mechanism. The sensor has also demonstrated a high selectivity for Hg2+ over other metal ions. A washing protocol was identified for sensor regeneration, allowing the probe to be re-used. The approach developed in this work can also be used for the preparation of sensors for other heavy metals

Improving Emirati students’ social responsibility competence through global citizenship education

Purpose: The purpose of this study is twofold: to determine if implementing a global citizenship education curriculum can aid the development of Emirati students’ social responsibility competence and to experiment with different instructional strategies that aim to yield improvement in the social responsibility of students. Design/methodology/approach: The intervention research study used a mixed-methods quasi-experimental approach to examine Emirati students’ social responsibility gains and overall perceptions of a global citizenship education curriculum. Conceptual frameworks for instructional design of service-learning were used as theoretical underpinnings. The data were collected from student reflections, field notes, questionnaires and interviews. Findings: Both the quantitative and qualitative data indicated that the global citizenship curriculum advanced students\u27 understanding of social responsibility and civic concepts, specifically civic awareness, social justice and diversity. Research limitations/implications: For future studies, researchers are encouraged to expand the current study\u27s five-week timeframe by exploring the implications of a global citizenship education curriculum over a full term or even a whole academic year. Practical implications: The results of the present study indicate that educators should experiment with curriculum redesign to further facilitate the development of social responsibility in undergraduate students. The results also suggest that educators incorporate specific instructional strategies such as integrated reflections and intergroup dialogue on social issues. Originality/value: Social responsibility and global citizenship education have broadly been based on Western paradigms. Few studies have explored the impact of global citizenship education on the development of students\u27 social responsibility in the Gulf region. This study fills the gap in knowledge by lending evidence of the role of global citizenship education in undergraduate university programs in the Gulf

The Effects of Racialization on European American Stress in the Nineteenth and Twentieth Centuries

This dissertation explores disparities in stress among European Americans (EA) and between EA and African Americans (AA) in racialized communities in the nineteenth and twentieth centuries. Comparisons among EA and between EA and AA are conducted to understand the biological consequences of racialization. Racialization is the process of assigning people to hierarchical categories for purposes of political, social, and economic discrimination. This dissertation investigates how racialization might have affected childhood stress using biocultural theory and facets of critical archaeology theory. Indicators of stress from skeletonized individuals in the William M. Bass Donated Skeletal Collection, Hamann-Todd Osteological Collection, and the Robert J. Terry Anatomical Skeletal Collection are used in this study. These indicators represent non-specific childhood stress and include measures of the anteroposterior (AP) and transverse (TR) diameters of the ventral neural canals (VNC) of the five lumbar vertebrae as well as linear enamel hypoplasia (LEH) frequency data from the maxillary central incisors and mandibular canines. Historical sources contextualize this investigation. The results of the finite mixture analysis (FMA) suggest that at least three phenotypically distinct groups of EA existed between 1828 and 1984. This study was not able to determine with certainty whether these EA groups represented particular racialized groups. Multiple analysis of variance (MANOVA) tests found a significant race effect with regard to late childhood /adolescent stress during the Early (1828-1881) period between EA and AA. AA had significantly smaller TR VNC diameters, suggesting they also experienced significantly more late childhood/adolescent stress. MANOVA tests also found significant sex effects during the Intermediate (1914-1945) and Late (1946-1984) periods. One-way analysis of variance (ANOVA) tests showed that early childhood stress, as demonstrated by AP VNC diameter and LEH decreased over time. ANOVA tests also showed that late childhood/adolescent stress, as demonstrated by TR VNC diameter, increased over time. The findings in this study suggest that explorations into the possible effects of racialization on population heterogeneity and stress heterogeneity are warranted and should also consider the intersection of various other identities such as sex, gender, class, language, religion, and nationality

A Fluorescent Optical Fibre Chemosensor for Mercury Detection

A proof-of-concept mercury probe was developed based on covalent attachment of a chemical coating to optical fibre. The sensing element comprised a dansyl derivative and crown ether moiety, acting as fluorophore and metal ion chelator respectively. An ON-OFF type fluorescence (quench) occurred upon binding of mercury ions, via an intramolecular charge transfer mechanism, in aqueous solution in the 909nM-90.9μM (247 ppb -24.7 ppm) concentration range. A washing protocol was identified for sensor regeneration allowing the probe to be re-used

TALON - The Telescope Alert Operation Network System: Intelligent Linking of Distributed Autonomous Robotic Telescopes

The internet has brought about great change in the astronomical community, but this interconnectivity is just starting to be exploited for use in instrumentation. Utilizing the internet for communicating between distributed astronomical systems is still in its infancy, but it already shows great potential. Here we present an example of a distributed network of telescopes that performs more efficiently in synchronous operation than as individual instruments. RAPid Telescopes for Optical Response (RAPTOR) is a system of telescopes at LANL that has intelligent intercommunication, combined with wide-field optics, temporal monitoring software, and deep-field follow-up capability all working in closed-loop real-time operation. The Telescope ALert Operations Network (TALON) is a network server that allows intercommunication of alert triggers from external and internal resources and controls the distribution of these to each of the telescopes on the network. TALON is designed to grow, allowing any number of telescopes to be linked together and communicate. Coupled with an intelligent alert client at each telescope, it can analyze and respond to each distributed TALON alert based on the telescopes needs and schedule.Comment: Presentation at SPIE 2004, Glasgow, Scotland (UK

Video Object Detection with an Aligned Spatial-Temporal Memory

We introduce Spatial-Temporal Memory Networks for video object detection. At its core, a novel Spatial-Temporal Memory module (STMM) serves as the recurrent computation unit to model long-term temporal appearance and motion dynamics. The STMM's design enables full integration of pretrained backbone CNN weights, which we find to be critical for accurate detection. Furthermore, in order to tackle object motion in videos, we propose a novel MatchTrans module to align the spatial-temporal memory from frame to frame. Our method produces state-of-the-art results on the benchmark ImageNet VID dataset, and our ablative studies clearly demonstrate the contribution of our different design choices. We release our code and models at http://fanyix.cs.ucdavis.edu/project/stmn/project.html

SkyDOT (Sky Database for Objects in the Time Domain): A Virtual Observatory for Variability Studies at LANL

The mining of Virtual Observatories (VOs) is becoming a powerful new method for discovery in astronomy. Here we report on the development of SkyDOT (Sky Database for Objects in the Time domain), a new Virtual Observatory, which is dedicated to the study of sky variability. The site will confederate a number of massive variability surveys and enable exploration of the time domain in astronomy. We discuss the architecture of the database and the functionality of the user interface. An important aspect of SkyDOT is that it is continuously updated in near real time so that users can access new observations in a timely manner. The site will also utilize high level machine learning tools that will allow sophisticated mining of the archive. Another key feature is the real time data stream provided by RAPTOR (RAPid Telescopes for Optical Response), a new sky monitoring experiment under construction at Los Alamos National Laboratory (LANL).Comment: to appear in SPIE proceedings vol. 4846, 11 pages, 5 figure

A suite of optical fibre-based chemical sensors for environmental monitoring

This paper is to review the research activities at City University London in the development of a suite of optical fibre-based chemical sensors, including pH, humidity and heavy metal sensors, for environmental monitoring

RAPTOR observations of delayed explosive activity in the high-redshift gamma-ray burst GRB 060206

The RAPid Telescopes for Optical Response (RAPTOR) system at Los Alamos National Laboratory observed GRB 060206 starting 48.1 minutes after gamma-ray emission triggered the Burst Alert Telescope (BAT) on-board the Swift satellite. The afterglow light curve measured by RAPTOR shows a spectacular re-brightening by ~1 mag about 1 h after the trigger and peaks at R ~ 16.4 mag. Shortly after the onset of the explosive re-brightening the OT doubled its flux on a time-scale of about 4 minutes. The total R-band fluence received from GRB 060206 during this episode is 2.3e-9 erg/cm2. In the rest frame of the burst (z = 4.045) this yields an isotropic equivalent energy release of ~0.7e50 erg in just a narrow UV band 130 +/- 22 nm. We discuss the implications of RAPTOR observations for untriggered searches for fast optical transients and studies of GRB environments at high redshift.Comment: Submitted to ApJ Letter

Wellbeing and Society: Towards Quantification of the Co-benefits of Wellbeing

This is the final version. Available on open access from Springer Verlag via the DOI in this recordThe objectives of this paper are twofold. First, it reviews the empirical evidence showing the existence of linkage between wellbeing and possible co-benefits, investigating in particular the positive effect that happiness and life satisfaction can have on health, social outcomes, employment, education and environmental behaviours. Second, it presents the valuation methods that have been proposed in the literature to place a monetary value on these outcomes. With wellbeing having become more and more relevant for individuals and policy makers, the full understanding of the co-benefits of wellbeing is central for the design and development of wellbeing interventions. As a consequence, the evaluation of the co-benefits of wellbeing is of crucial importance for the appropriate allocation of resources towards such strategies.Innovate U