The formation of biofilm by bacteria confers resistance to biocides and presents problems in medical and veterinary clinical settings. Here we report the effect of carvacrol, one of the major ...antimicrobial components of oregano oil, on the formation of biofilms and its activity on existing biofilms. Assays were carried out in polystyrene microplates to observe (a) the effect of 0-0.8 mM carvacrol on the formation of biofilms by selected bacterial pathogens over 24 h and (b) the effect of 0-8 mM carvacrol on the stability of pre-formed biofilms. Carvacrol was able to inhibit the formation of biofilms of Chromobacterium violaceum ATCC 12472, Salmonella enterica subsp. Typhimurium DT104, and Staphylococcus aureus 0074, while it showed no effect on formation of Pseudomonas aeruginosa (field isolate) biofilms. This inhibitory effect of carvacrol was observed at sub-lethal concentrations (<0.5 mM) where no effect was seen on total bacterial numbers, indicating that carvacrol's bactericidal effect was not causing the observed inhibition of biofilm formation. In contrast, carvacrol had (up to 8 mM) very little or no activity against existing biofilms of the bacteria described, showing that formation of the biofilm also confers protection against this compound. Since quorum sensing is an essential part of biofilm formation, the effect of carvacrol on quorum sensing of C. violaceum was also studied. Sub-MIC concentrations of carvacrol reduced expression of cviI (a gene coding for the N-acyl-L-homoserine lactone synthase), production of violacein (pigmentation) and chitinase activity (both regulated by quorum sensing) at concentrations coinciding with carvacrol's inhibiting effect on biofilm formation. These results indicate that carvacrol's activity in inhibition of biofilm formation may be related to the disruption of quorum sensing.
The United Arab Emirates (UAE) host valuable coastal and marine biodiversity that is subjected to multiple pressures under extreme conditions. To mitigate impacts on marine ecosystems, the UAE ...protects almost 12% of its Exclusive Economic Zone. This study mapped and validated the distribution of key coastal and marine habitats, species and critical areas for their life cycle in the Gulf area of the UAE. We identified gaps in the current protection of these ecological features and assessed the quality of the data used. The overall dataset showed good data quality, but deficiencies in information for the coastline of the north-western emirates. The existing protected areas are inadequate to safeguard key ecological features such as mangroves and coastal lagoons. This study offers a solid basis to understand the spatial distribution and protection of marine biodiversity in the UAE. This information should be considered for implementing effective conservation planning and ecosystem-based management.
•Mapping species and habitats is necessary for effective ecosystem-based management.•We compiled data to map marine and coastal biodiversity distribution in the UAE.•Data quality assessment showed that data are sufficient to guide management.•Current MPA extension is insufficient to safeguard some habitats such as mangroves.•The information provided should be used in future conservation plans and management.
The Science and Technology of Particle Accelerators provides an accessible introduction to the field, and is suitable for advanced undergraduates, graduate students, and academics, as well as ...professionals in national laboratories and facilities, industry, and medicine who are designing or using particle accelerators. Providing integrated coverage of accelerator science and technology, this book presents the fundamental concepts alongside detailed engineering discussions and extensive practical guidance, including many numerical examples. For each topic, the authors provide a description of the physical principles, a guide to the practical application of those principles, and a discussion of how to design the components that allow the application to be realised. Features: Written by an interdisciplinary and highly respected team of physicists and engineers from the Cockcroft Institute of Accelerator Science and Technology in the UK Accessible style, with many numerical examples Contains an extensive set of problems, with fully worked solutions available Rob Appleby is an academic member of staff at the University of Manchester, and Chief Examiner in the Department of Physics and Astronomy. Graeme Burt is an academic member of staff at the University of Lancaster, and previous Director of Education at the Cockcroft Institute. James Clarke is head of Science Division in the Accelerator Science and Technology Centre at STFC Daresbury Laboratory. Hywel Owen is an academic member of staff at the University of Manchester, and Director of Education at the Cockcroft Institute. All authors are researchers within the Cockcroft Institute of Accelerator Science and Technology and have extensive experience in the design and construction of particle accelerators, including particle colliders, synchrotron radiation sources, free electron lasers, and medical and industrial accelerator systems.
Background:
Autologous haematopoietic stem cell transplantation (AHSCT) is an effective treatment for patients with multiple sclerosis (MS) who have highly active disease, despite the use of standard ...disease-modifying therapies (DMTs). However, the optimal time for offering AHSCT to patients with ‘aggressive’ MS is yet to be established.
Objectives:
The objective was to explore the safety and efficacy of AHSCT as a first-line DMT in patients with ‘aggressive’ MS.
Methods:
All patients with ‘aggressive’ MS who received AHSCT as a first-line DMT in five European and North American centres were retrospectively evaluated.
Results:
Twenty patients were identified. The median interval between diagnosis and AHSCT was 5 (1–20) months. All had multiple poor prognostic markers with a median pre-transplant Expanded Disability Status Scale (EDSS) score of 5.0 (1.5–9.5). After a median follow-up of 30 (12–118) months, the median EDSS score improved to 2.0 (0–6.5, p < 0.0001). No patient had further relapses. Three had residual magnetic resonance imaging (MRI) disease activities in the first 6 months post-transplant, but no further new or enhancing lesions were observed in subsequent scans.
Conclusion:
AHSCT is safe and effective as a first-line DMT in inducing rapid and sustained remission in patients with ‘aggressive’ MS.
Abstract
With the increase in antibiotic-resistant bacteria and the lack of new antibiotics being brought onto the market, alternative strategies need to be found to cope with infections resulting ...from drug-resistant bacteria. A possible solution may be to combine existing antibiotics with phytochemicals to enhance the efficacy of antibiotics. A group of phytochemicals that is said to have such effects, according to in vitro studies, is essential oils (EOs) and their components. Amongst others, EOs containing carvacrol, cinnamaldehyde, cinnamic acid, eugenol and thymol can have a synergistic effect in combination with antibiotics. Several modes of action have been put forward by which antibiotics and the essential oil components may act synergistically, such as by affecting multiple targets; by physicochemical interactions and inhibiting antibacterial-resistance mechanisms. Many reported assays show additivity or moderate synergism, indicating that EOs may offer possibilities for reducing antibiotic use.
The development of desalination has been essential to the rapid economic development of the countries bordering the Arabian Gulf. The current production capacity of sea water desalination plants ...drawing water from Gulf is over 20 million m3 day−1, which may rise to 80 million m3 day−1 by 2050. Whilst supporting aspects of sustainable development related to water and sanitation, desalination impacts the marine environment through impingement and entrainment of organisms in intakes, and through thermal, brine and chemical discharges. This may compromise other objectives for sustainable development related to sustainable use of the oceans. Under business as usual scenarios, by 2050, the impact of individual desalination plants will combine causing a regional scale impact. Without mitigating actions to avoid the business as usual scenario, by 2050, desalination in combination with climate change, will elevate coastal water temperatures across more than 50% of the Gulf by at least 3 °C, and a volume of water equivalent to more than a third of the total volume of water between 0 and 10 m deep will pass through desalination plants each year. This will adversely impact the coastal ecosystem of the Gulf, with impacts on biodiversity, fisheries and coastal communities and may cause potential loss of species and habitats from the Gulf. Given the significant implications of these preliminary findings, and in light of the precautionary approach to management, it is recommended that mitigating options addressing behavioural, regulatory and technological change are rapidly evaluated and implemented to avoid the development of desalination in the region along a business as usual pathway, and multidisciplinary research studies should be conducted to reduce uncertainty in predictions of future impacts.
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•Desalination in the Arabian Gulf both supports and threatens sustainable development.•Impacts of individual desalination plants will combine to cause regional impact.•Desalination will adversely impact biodiversity, fisheries, and coastal communities.•Desalination will magnify the impact of climate change on the Gulf.•Minimising impacts requires behavioural, regulatory, and technological development.
We report studies of ultrahigh-energy cosmic-ray composition via analysis of depth of air shower maximum (X(max)), for air shower events collected by the High-Resolution Fly's Eye (HiRes) ...observatory. The HiRes data are consistent with a constant elongation rate d<X(max)>/dlog(E) of 47.9+/-6.0(stat)+/-3.2(syst) g/cm2/decade for energies between 1.6 and 63 EeV, and are consistent with a predominantly protonic composition of cosmic rays when interpreted via the QGSJET01 and QGSJET-II high-energy hadronic interaction models. These measurements constrain models in which the galactic-to-extragalactic transition is the cause of the energy spectrum ankle at 4x10(18) eV.
Coral reefs are one of the most biodiverse and economically important ecosystems in the world, but they are rapidly degrading due to the effects of global climate change and local anthropogenic ...stressors. Reef scientists are increasingly studying coral reefs that occur in marginal and extreme environments to understand how organisms respond to, and cope with, environmental stress, and to gain insight into how reef organisms may acclimate or adapt to future environmental change. To date, there have been more than 860 publications describing the biology and/or abiotic conditions of marginal and extreme reef environments, most of which were published within the past decade. These include systems characterized by unusually high, low, and/or variable temperatures (intertidal, lagoonal, high-latitude areas, and shallow seas), turbid or urban environments, acidified habitats, and mesophotic depth, and focus on reefs geographically spread throughout most of the tropics. The papers in this special issue of Coral Reefs, entitled
Coral Reefs in a Changing World: Insights from Extremes
, build on the growing body of literature on these unique and important ecosystems, providing a deeper understanding of the patterns and processes governing life in marginal reef systems, and the implications that these insights may have for the future of tropical coral reefs in our rapidly changing world.
The new standard C37.118.1 lays down strict performance limits for phasor measurement units (PMUs) under steady-state and dynamic conditions. Reference algorithms are also presented for the ...performance (P) and measurement (M) class PMUs. In this paper, the performance of these algorithms is analyzed during some key signal scenarios, particularly those of offnominal frequency, frequency ramps, and harmonic contamination. While it is found that total vector error (TVE) accuracy is relatively easy to achieve, the reference algorithm is not able to achieve a useful rate of change of frequency (ROCOF) accuracy. Instead, this paper presents alternative algorithms for P and M class PMUs, which use adaptive filtering techniques in real time up to 10-kHz sample rates, allowing consistent accuracy to be maintained across a ±33% frequency range. ROCOF errors can be reduced by factors of > 40 for P class and > 100 for M class devices.
More than 11 genetic causes of severe combined immunodeficiency (SCID) have been identified, affecting development and/or function of T lymphocytes, and sometimes B lymphocytes and natural killer ...(NK) cells. Deletion of 22q11.2 is associated with immunodeficiency, although less than 1% of cases are associated with T-B + NK + SCID phenotype. Severe immunodeficiency with CHARGE syndrome has been noted only rarely Omenn syndrome is a rare autosomal recessive form of SCID with erythroderma, hepatosplenomegaly, lymphadenopathy and alopecia. Hypomorphic recombination activating genes 1 and 2 mutations were first described in patients with Omenn syndrome. More recently, defects in Artemis, RMRP, IL7Rα and common gamma chain genes have been described. We describe four patients with mutations in CHD7, who had clinical features of CHARGE syndrome and who had T-B + NK + SCID (two patients) or clinical features consistent with Omenn syndrome (two patients). Immunodeficiency in patients with DiGeorge syndrome is well recognized - CHARGE syndrome should now be added to the causes of T-B + NK + SCID, and mutations in the CHD7 gene may be associated with Omenn-like syndrome.
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