Evaluation of a low cost solid-state accelerometer as a distance measuring sensor for vehicle positioning system

This paper describes an evaluation of a low cost, solid state accelerometer as a distance-measuring device. Kalman filter was applied to reduce random noise existing in the sensor. The random bias drift of the accelerometer was found to be 2.5 mg. The accelerometer was moved back and forth eight times for a distance of 40 cm with an acceleration of 10 m/s2 and the distance error accumulated +1.55 cm. The bias drift rate due to temperature was 0.108 μg/s when the accelerometer was placed at room temperature. The performance shows that the device is suitable for short duration distance measurement and may act as a complementary sensor to the GPS during signal blockage or between periodical absolute position updates.published_or_final_versio

Optical wireless based on high brightness visible LEDs

This paper is on a novel use of lighting or signaling devices constructed by light-emitting diodes (LEDs). The idea is on their concurrent use for simultaneous signaling and communications. The visible light from LEDs can be modulated and encoded with audio or data signal. Hence, an LED indicator lamp or traffic light can become an information broadcasting device. Such a system made up of high brightness visible LEDs can provide the function of open space, wireless broadcasting of audio or data signal. An implemented system with experimental results is shown. A portable receiver is designed to demodulate the optically transmitted information. The distance for audio transmission of an LED traffic light can reach over 20m. The optical link employs intensity modulation with direct detection. The system is limited to line-of-sight communications. However, this concurrent use of LEDs will open up many new applications.published_or_final_versio

The association between ethnicity and the delay time in seeking medical care for chest pain: a systematic review

Made available in accordance with the Publisher's Author's Permissions policyBackground: Acute coronary syndrome (ACS) is a leading cause of mortality and morbidity worldwide, and chest pain is one of the most common symptoms of ACSs. A rapid response to chest pain by patients and appropriate management by health professionals are vital to improve survival rates. People from different ethnic groups are likely to have different perceptions of chest pain, its severity and the need for urgent treatment. These differences in perception may contribute to differences in response to chests pain and precipitate unique coping strategies. Delay in seeking medical care for chest pain in the general population has been well documented; however, limited studies have focused on delay times within ethnic groups. There is little research to date as to whether ethnicity is associated with the time taken to seek medical care for chest pain. Consequently, addressing this gap in knowledge will play a crucial role in improving the health outcomes of culturally and linguistically diverse (CALD) patients suffering from chest pain and for developing appropriate clinical practice and public awareness for these populations. Objectives: The current review aimed to determine if there is an association between ethnicity and delay in seeking medical care for chest pain among CALD populations. Inclusion criteria Types of participants: Patients from different ethnic minority groups presenting to emergency departments (EDs) with chest pain. Types of exposure: The current review will examine studies that evaluate the association between ethnicity and delay in seeking medical care for chest pain among CALD populations. Types of studies: The current review will consider quantitative studies including randomized controlled trials (RCTs), non-RCTs, quasi-experimental, before and after studies, prospective and retrospective cohort studies, case-control studies and analytical cross-sectional studies. Outcomes: The current review will consider studies that measure delay time as the main outcome. The time will be measured as the interval between the time of symptom onset and time to reach an ED. Search strategy: A comprehensive search was undertaken for relevant published and unpublished studies written in English with no date restriction. All searches were conducted in October 2014. We searched the following databases: MEDLINE, PubMed, Cochrane Central Register of Controlled Trials, Embase, Cumulative Index to Nursing and Allied Health Literature (CINAHL), PsycINFO, ProQuest (health databases only), Informit, Sociological Abstracts, Scopus and Web of Science. The search for unpublished studies included a wide range of ‘gray literature’ sources including national libraries, digital theses repositories and clinical trial registries. We also targeted specific health research, specialist cardiac, migrant health, and emergency medicine organizational websites and/or conferences. We also checked the reference lists of included studies and contacted authors when further details about reported data was required to make a decision about eligibility. Methodological quality: Papers selected for retrieval were assessed by two independent reviewers for methodological validity prior to being included in the review. Validity was assessed using standardized critical appraisal instruments from the Joanna Briggs Institute. Adjudication was produced by the third reviewer. Data extraction: Data were extracted from included articles by two independent reviewers using the standardized data extraction tool from the Joanna Briggs Institute. Data synthesis: The extracted data were synthesized into a narrative summary. Meta-analysis could not be performed due to the heterogeneity of study protocols and methods used to measure outcomes. Results: A total of 10 studies, with a total of 1,511,382 participants, investigating the association between ethnicity and delay met the inclusion criteria. Delay times varied across ethnic groups, including Black, Hispanic, Asian, South Asian, Southeast Asian and Chinese. Seven studies reported delay in hours and ranged from 1.90 to 3.10 h. Delay times were longer among CALD populations than the majority population. The other three studies reported delay time in categories of time (e.g. <1, <4 and <6 h) and found larger proportions of later presentations to the EDs among ethnic groups compared with the majority groups. Conclusion: There is evidence of an association between ethnicity and time taken in seeking medical care for chest pain, with patients from some ethnic minorities (e.g. Black, Asian, Hispanic and South Asian) taking longer than those of the majority population. Health promotions and health campaigns focusing on these populations are indicated

A comparison of LKB1/AMPK/mTOR metabolic axis response to global ischaemia in brain, heart, liver and kidney in a rat model of cardiac arrest

© The Author(s). 2018 This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Abstract Background Cellular energy failure in high metabolic rate organs is one of the underlying causes for many disorders such as neurodegenerative diseases, cardiomyopathies, liver and renal failures. In the past decade, numerous studies have discovered the cellular axis of LKB1/AMPK/mTOR as an essential modulator of cell homeostasis in response to energy stress. Through regulating adaptive mechanisms, this axis adjusts the energy availability to its demand by a systematized control on metabolism. Energy stress, however, could be sensed at different levels in various tissues, leading to applying different strategies in response to hypoxic insults. Methods Here the immediate strategies of high metabolic rate organs to time-dependent short episodes of ischaemia were studied by using a rat model (n = 6/group) of cardiac arrest (CA) (15 and 30 s, 1, 2, 4 and 8 min CA). Using western blot analysis, we examined the responses of LKB1/AMPK/mTOR pathway in brain, heart, liver and kidney from 15 s up to 8 min of global ischaemia. The ratio of ADP/ATP was assessed in all ischemic and control groups, using ApoSENSOR bioluminescent assay kit. Results Brain, followed by kidney showed the early dephosphorylation response in AMPK (Thr172) and LKB1 (Ser431); in the absence of ATP decline (ADP/ATP elevation). Dephosphorylation of AMPK was followed by rephosphorylation and hyperphosphorylation, which was associated with a significant ATP decline. While heart’s activity of AMPK and LKB1 remained at the same level during short episodes of ischaemia, liver’s LKB1 was dephosphorylated after 2 min. AMPK response to ischaemia in liver was mainly based on an early alternative and a late constant hyperphosphorylation. No significant changes was observed in mTOR activity in all groups. Conclusion Together our results suggest that early AMPK dephosphorylation followed by late hyperphosphorylation is the strategy of brain and kidney in response to ischaemia. While the liver seemed to get benefit of its AMPK system in early ischameia, possibly to stabilize ATP, the level of LKB1/AMPK activity in heart remained unchanged in short ischaemic episodes up to 8 min. Further researches must be conducted to elucidate the molecular mechanism underlying LKB1/AMPK response to oxygen supply

Archaean crustal evolution in West Africa: A new synthesis of the Archaean geology in Sierra Leone, Liberia, Guinea and Ivory Coast

A new synthesis of the geology and geochronology of the little-known Archaean rocks in Sierra Leone, Liberia, Guinea and Ivory Coast is presented in order to better understand the processes of Archaean crustal evolution in this region, and to attempt to interpret these data in the light of our current understanding of Archaean crustal evolution. In addition, this study seeks to identify those aspects of Archaean crustal evolution which are currently not known in this area and which need to become the subject of future studies, given the economic importance of this region in terms of the mineral deposits hosted in the Archaean rocks. These include greenstone-belt hosted iron ore, lode gold, chromite and columbite-tantalite and younger diamondiferous kimberlites intrusive into Archaean felsic gneisses. The new results show that this cratonic nucleus comprises of four main geological units: 1. The oldest crust is made up of 3.5-3.6 Ga TTG (tonalite-trondjemite-granodiorite) gneisses. These only outcrop in the east of the craton in Guinea but their presence is indicated elsewhere in the central part of the craton though xenocrystic zircon cores in younger rocks. 2. The major rock type found throughout the craton is 3.26-2.85 Ga TTG gneiss. In detail these magmas are thought to have formed in two episodes one between 3.05-3.26 Ga and the other between 2.85-2.96 Ga. The presence of inherited zircons in the younger suite indicate that this event represents the partial reworking of the older gneisses. 3.4 Ga eclogite xenoliths in kimberlite derived from the sub-continental lithospheric mantle are thought to be the restite after the partial melting of a basaltic protolith in the production of the TTG magmas. 3. Supracrustal rocks form linear belts infolded into the TTG gneisses and metamorphosed to amphibolite and granulite grade. They are of different sizes, contain a variety of lithological sequences and may be of several different ages. The larger supracrustal belts in Sierra Leone contain a thick basalt-komatiite sequence derived by the partial melting of two different mantle sources, unconformably overlain by a sedimentary formation. They are seen as an important resource for gold, iron-ore, chromite and columbite-tantalite. 4. A suite of late Archaean granitoids formed by the partial melting of the TTG gneisses in a craton wide deformation-metamorphic-partial melting event at 2800 +/- 20 Ma. This thermal event is thought to be responsible for the stabilisation of the craton. This new synthesis highlights major geological and geochronological similarities between the Archaean rocks of Sierra Leone, Liberia, Guinea and Ivory Coast and those in the Reguibat Shield in the northern part of the West African Craton suggesting that the two regions were once more closely related.UoD URS

Prioritizing Land and Sea Conservation Investments to Protect Coral Reefs

Background: Coral reefs have exceptional biodiversity, support the livelihoods of millions of people, and are threatened by multiple human activities on land (e.g. farming) and in the sea (e.g. overfishing). Most conservation efforts occur at local scales and, when effective, can increase the resilience of coral reefs to global threats such as climate change (e.g. warming water and ocean acidification). Limited resources for conservation require that we efficiently prioritize where and how to best sustain coral reef ecosystems

Accommodating Dynamic Oceanographic Processes and Pelagic Biodiversity in Marine Conservation Planning

Pelagic ecosystems support a significant and vital component of the ocean's productivity and biodiversity. They are also heavily exploited and, as a result, are the focus of numerous spatial planning initiatives. Over the past decade, there has been increasing enthusiasm for protected areas as a tool for pelagic conservation, however, few have been implemented. Here we demonstrate an approach to plan protected areas that address the physical and biological dynamics typical of the pelagic realm. Specifically, we provide an example of an approach to planning protected areas that integrates pelagic and benthic conservation in the southern Benguela and Agulhas Bank ecosystems off South Africa. Our aim was to represent species of importance to fisheries and species of conservation concern within protected areas. In addition to representation, we ensured that protected areas were designed to consider pelagic dynamics, characterized from time-series data on key oceanographic processes, together with data on the abundance of small pelagic fishes. We found that, to have the highest likelihood of reaching conservation targets, protected area selection should be based on time-specific data rather than data averaged across time. More generally, we argue that innovative methods are needed to conserve ephemeral and dynamic pelagic biodiversity

Integrated planning for land-sea ecosystem connectivity to protect coral reefs

Coral reefs are threatened by human activities both on the land and in the sea. However, standard approaches for prioritizing locations for marine and terrestrial reserves neglect to consider connections between ecosystems. We demonstrate an integrated approach for coral reef conservation with the objective of prioritizing marine reserves close to catchments with high forest cover in order to facilitate ecological processes that rely upon intact land-sea protected area connections and minimize negative impact of land-based runoff on coral reefs. Our aims are to (1) develop and apply simple models of connections between ecosystems that require little data and (2) incorporate different types of connectivity models into spatial conservation prioritization. We compared how, if at all, the locations and attributes (e.g., costs) of priorities differ from an approach that ignores connections. We analyzed spatial prioritization plans that allow for no connectivity, adjacent connectivity in the sea, symmetric and asymmetric land-sea connectivity, and the combination of adjacent connectivity in the sea and asymmetric land-sea connectivity. The overall reserve system costs were similar for all scenarios. We discovered that integrated planning delivered substantially different spatial priorities compared to the approach that ignored connections. Only 11-40% of sites that were high priority for conservation were similar between scenarios with and without connectivity. Many coral reefs that were a high priority when we considered adjacent connectivity in the sea and ignored land-sea connectivity were assigned to low priorities when symmetric land-sea connectivity was included, and vice versa. Our approach can be applied to incorporate connections between ecosystems. (C) 2013 Elsevier Ltd. All rights reserved

Risk factors for back, neck and shoulder musculoskeletal injuries and claims in ambulance officers

Relatively little has been published on the range of risk factors contributing to musculoskeletal injuries in ambulance officers. This study aims to identify perceived risk factors for back, neck and shoulder musculoskeletal injuries and claims in relation to working conditions, and the physical and psychological demands of the job. This was a cross-sectional study using an internet-based survey in an Australian ambulance service. The survey included demographic questions and questions on psychosocial factors related to the job and the way in which work is organized, musculoskeletal injuries sustained and claims submitted in the previous 12 months; and two open ended questions on perceived risk factors for injury and injury risk mitigation strategies. Ambulance officers who felt they were able to take sufficient breaks were less likely to sustain a back, neck or shoulder musculoskeletal injury, and those who perceived their work required high levels of physical effort were more likely to submit a claim for these injuries. Two important perceived causal factors contributing to musculoskeletal injuries were the uncontrolled environment and non-adherence to manual handling techniques. However, suggested risk mitigation strategies of improving fitness and manual handling training, were not supported by the quantitative analysis