Increasing spatiotemporal proximity of heat and precipitation extremes in a warming world quantified by a large model ensemble

Increases in climate hazards and their impacts mark one of the major challenges of climate change. Situations in which hazards occur close enough to one another to result in amplified impacts, because systems are insufficiently resilient or because hazards themselves are made more severe, are of special concern. We consider projected changes in such compounding hazards using the MPI Grand Ensemble under the moderate (RCP4.5) emissions scenario, which produces warming of about 2.25°C between pre-industrial (1851-1880) and 2100. We find that extreme heat events occurring on 3 or more consecutive days increase in frequency by 100-300%, and consecutive extreme precipitation events increase in most regions, nearly doubling for some. The chance of concurrent heat and drought leading to simultaneous maize failures in 3 or more breadbasket regions increases by about 50%, while interannual wet-dry oscillations become at least 20% more likely across much of the subtropics. Our results highlight the importance of taking compounding climate extremes into account when looking at possible tipping points of socio-environmental systems

A mechatronics approach to develop STEM accessibility tools for visually impaired students

This paper is focusing on how to develop a suitable educational platform for visually impaired students to access STEM (Science, Technology, Engineering and Mathematics) learning materials without depending any printed materials. It is a challenge for the visually impaired students to learn STEM subjects because visual information. The first part of this paper will be an overview about the visually impaired students and also their challenges in STEM learning. The next part will be an overview on the invention of learning kits, devices and technology to help the visually impaired students to access knowledge and information as well as for STEM learning. Finally, we proposed with our concept of tactile display device that can be used for STEM teaching and learning for visually impaired students based on Mechatronics approach. Currently, we have developed a system that can create and process digital images to be displayed in tactile graphic format and it is supported with a GUI system. In this paper, we have demonstrated our initial concept prototype. In future, the system will be adapted to any platform or devices that can display tactile graphics

A Rapid Assessment of Avoidable Blindness in Southern Zambia

INTRODUCTION: A rapid assessment of avoidable blindness (RAAB) was conducted in Southern Zambia to establish the prevalence and causes of blindness in order to plan effective services and advocate for support for eye care to achieve the goals of VISION 2020: the right to sight. METHODS: Cluster randomisation was used to select villages in the survey area. These were further subdivided into segments. One segment was selected randomly and a survey team moved from house to house examining everyone over the age of 50 years. Each individual received a visual acuity assessment and simple ocular examination. Data was recorded on a standard proforma and entered into an established software programme for analysis. RESULTS: 2.29% of people over the age of 50 were found to be blind (VA <3/60 in the better eye with available correction). The major cause of blindness was cataract (47.2%) with posterior segment disease being the next main cause (18.8%). 113 eyes had received cataract surgery with 30.1% having a poor outcome (VA <6/60) following surgery. Cataract surgical coverage showed that men (72%) received more surgery than women (65%). DISCUSSION: The results from the RAAB survey in Zambia were very similar to the results from a similar survey in Malawi, where the main cause of blindness was cataract but posterior segment disease was also a significant contributor. Blindness in this part of Zambia is mainly avoidable and there is a need for comprehensive eye care services that can address both cataract and posterior segment disease in the population if the aim of VISION 2020 is to be achieved. Services should focus on quality and gender equity of cataract surgery

Inflammatory cytokines and biofilm production sustain Staphylococcus aureus outgrowth and persistence: A pivotal interplay in the pathogenesis of Atopic Dermatitis

Individuals with Atopic dermatitis (AD) are highly susceptible to Staphylococcus aureus colonization. However, the mechanisms driving this process as well as the impact of S. aureus in AD pathogenesis are still incompletely understood. In this study, we analysed the role of biofilm in sustaining S. aureus chronic persistence and its impact on AD severity. Further we explored whether key inflammatory cytokines overexpressed in AD might provide a selective advantage to S. aureus. Results show that the strength of biofilm production by S. aureus correlated with the severity of the skin lesion, being significantly higher (P < 0.01) in patients with a more severe form of the disease as compared to those individuals with mild AD. Additionally, interleukin (IL)-β and interferon γ (IFN-γ), but not interleukin (IL)-6, induced a concentration-dependent increase of S. aureus growth. This effect was not observed with coagulase-negative staphylococci isolated from the skin of AD patients. These findings indicate that inflammatory cytokines such as IL1-β and IFN-γ, can selectively promote S. aureus outgrowth, thus subverting the composition of the healthy skin microbiome. Moreover, biofilm production by S. aureus plays a relevant role in further supporting chronic colonization and disease severity, while providing an increased tolerance to antimicrobials

A proposal for multi-tens of GW fully coherent femtosecond soft X-ray lasers

X-ray free-electron lasers1,2 delivering up to 131013 coherent photons in femtosecond pulses are bringing about a revolution in X-ray science3?5. However, some plasma-based soft X-ray lasers6 are attractive because they spontaneously emit an even higher number of photons (131015), but these are emitted in incoherent and long (hundreds of picoseconds) pulses7 as a consequence of the amplification of stochastic incoherent self-emission. Previous experimental attempts to seed such amplifiers with coherent femtosecond soft X-rays resulted in as yet unexplained weak amplification of the seed and strong amplification of incoherent spontaneous emission8. Using a time-dependent Maxwell?Bloch model describing the amplification of both coherent and incoherent soft X-rays in plasma, we explain the observed inefficiency and propose a new amplification scheme based on the seeding of stretched high harmonics using a transposition of chirped pulse amplification to soft X-rays. This scheme is able to deliver 531014 fully coherent soft X-ray photons in 200 fs pulses and with a peak power of 20 GW

The Search for Gravitational Waves

Experiments aimed at searching for gravitational waves from astrophysical sources have been under development for the last 40 years, but only now are sensitivities reaching the level where there is a real possibility of detections being made within the next five years. In this article a history of detector development will be followed by a description of current detectors such as LIGO, VIRGO, GEO 600, TAMA 300, Nautilus and Auriga. Preliminary results from these detectors will be discussed and related to predicted detection rates for some types of sources. Experimental challenges for detector design are introduced and discussed in the context of detector developments for the future.Comment: 21 pages, 7 figures, accepted J. Phys. B: At. Mol. Opt. Phy

Comparison of age-specific cataract prevalence in two population-based surveys 6 years apart

BACKGROUND: In this study, we aimed to compare age-specific cortical, nuclear and posterior subcapsular (PSC) cataract prevalence in two surveys 6 years apart. METHODS: The Blue Mountains Eye Study examined 3654 participants (82.4% of those eligible) in cross-section I (1992–4) and 3509 participants (75.1% of survivors and 85.2% of newly eligible) in cross-section II (1997–2000, 66.5% overlap with cross-section I). Cataract was assessed from lens photographs following the Wisconsin Cataract Grading System. Cortical cataract was defined if cortical opacity comprised ≥ 5% of lens area. Nuclear cataract was defined if nuclear opacity ≥ Wisconsin standard 4. PSC was defined if any present. Any cataract was defined to include persons who had previous cataract surgery. Weighted kappa for inter-grader reliability was 0.82, 0.55 and 0.82 for cortical, nuclear and PSC cataract, respectively. We assessed age-specific prevalence using an interval of 5 years, so that participants within each age group were independent between the two surveys. RESULTS: Age and gender distributions were similar between the two populations. The age-specific prevalence of cortical (23.8% in 1(st), 23.7% in 2(nd)) and PSC cataract (6.3%, 6.0%) was similar. The prevalence of nuclear cataract increased slightly from 18.7% to 23.9%. After age standardization, the similar prevalence of cortical (23.8%, 23.5%) and PSC cataract (6.3%, 5.9%), and the increased prevalence of nuclear cataract (18.7%, 24.2%) remained. CONCLUSION: In two surveys of two population-based samples with similar age and gender distributions, we found a relatively stable cortical and PSC cataract prevalence over a 6-year period. The increased prevalence of nuclear cataract deserves further study

Developing the specifications of an Open Angle Glaucoma screening intervention in the United Kingdom : a Delphi approach

PMID: 23216983 [PubMed - indexed for MEDLINE] PMCID: PMC3563574 Free PMC Article Acknowledgements We thank all the glaucoma specialists who took part in the Delphi process. We thank the Glaucoma screening Platform Study advisory panel including R Bativala, D Crabb, D Garway-Heath, M Griffiths, R Hitchings; S McPherson, A Tuulonen, A Viswanathan, H Waterman, R Wormald, D Wright for their guidance and contribution to the Delphi process and Luke Vale and Rodolfo Hernandez for their advice on development of the Delphi questionnaires. This paper was developed from the first phase of a project funded by the MRC (project reference G0701759) Developing the intervention & outcome components of a proposed randomized controlled trial of screening for open angle glaucoma. The Health Services Research Unit is core funded by the Chief Scientist Office of the Scottish Government Health Directorates. The views expressed in this report are those of the authors and not necessarily those of the funders.Peer reviewedPublisher PD