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Genotypic and phenotypic diversity differences of presumptive commensal and avian pathogenic E. coli
1. The objective of the experiment was to characterise the genotypic and phenotypic differences between presumptive commensal E. coli and avian pathogenic E. coli (APEC) of poultry.
2. DNA was extracted from 65 confirmed APEC E. coli from chicken, 100 presumptive commensal E. coli from healthy turkey and 35 from healthy chicken. Enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) and virulence factors genotyping was performed to characterise genetic features.
3. Carbon source utilisation and antimicrobial susceptibility tests were performed to characterise phenotypic features of isolates.
4. The genetic divergence between E. coli strains tested by ERIC-PCR profiles and virulence associated genes showed a clear genetic separation between E. coli APEC and turkey E. coli strains.
5. The carbon utilisation profile of turkey isolates was different from chicken and APEC strains; whereas antimicrobial susceptibility was highest for turkey isolates (53%), and lowest for APEC strains (33.8%).
6. The study showed a significant negative correlation between utilisation of arabitol and adonitol with different virulence determinants tested, which suggests that the ability to utilise some uncommon carbon sources may be used to discriminate between presumptive commensal E. coli and APEC
Syntheses of 7-substituted anthra[2,3-b]thiophene derivatives and naphtho[2,3-b:6,7-b’]dithiophene
7-R-anthra[2,3-b]thiophene derivatives (1, R = H, Me, i-Pr, MeO) are prepared in three steps (in average overall yield >50%) starting from (E)-4-RC6H4CH2(HOCH2)C=CI(CH2OH). The latter are commercial or readily prepared from 2-butyne-1,4-diol and ArCH2Cl (both costin
Passive smoking, as measured by hair nicotine, and severity of acute lower respiratory illnesses among children
The aim of this study was to describe the association between passive smoking and the severity of acute lower respiratory illnesses (ALRI) among 351 children aged 3–27 months admitted to hospital. A total of 297 children provided hair samples, which were analysed for hair nicotine levels as an indicator of passive smoking. A severity of illness grading system was developed by using clinical and management criteria used by the medical staff at hospital. The OR for children with more severe illness being exposed to higher nicotine levels was 1.2, 95% CI: 0.57–2.58 when using dichotomised respiratory severity levels and upper versus lower nicotine quartile levels. In an ordinal logistic regression model, the OR of more severe illness being associated with higher nicotine levels was 1.07 (95% CI: 0.92–1.25). When analysis was limited to the more severe cases, the OR of the least severe category compared to the most severe category, in relation to nicotine levels in hair, was 1.79 (95% CI: 0.5–6.30). The ordinal logistic regression of this group of severely-ill children (OR 1.1 (95% CI: 0.94–1.29) was not substantially different from the overall study subjects
Sex-Specific differences in cardiovascular risk, risk factors and risk management in the peripheral arterial disease population
Cardiovascular disease (CVD) is the leading cause of mortality in women worldwide but has been primarily recognised as a man’s disease. The major components of CVD are ischaemic heart disease (IHD), stroke and peripheral arterial disease (PAD). Compared with IHD or stroke, individuals with PAD are at significantly greater risk of major cardiovascular events. Despite this, they are less likely to receive preventative treatment than those with IHD. Women are at least as affected by PAD as men, but major sex-specific knowledge gaps exist in the understanding of relevant CVD risk factors and efficacy of treatment. This prompted the American Heart Association to issue a “call to action” for PAD in women, in 2012. Despite this, PAD and CVD risk in women continues to be under-recognised, leading to a loss of opportunity to moderate and prevent CVD morbidity. This review outlines current evidence regarding cardiovascular risk in women and men with PAD, the relative significance of traditional and non-traditional risk factors and sex differences in cardiovascular risk managemen
China’s Sudan engagement: changing Northern and Southern political trajectories in peace and war
China has developed a more consequential role in Sudan over the past two decades, during which it has become bound up in the combination of enduring violent internal instability and protracted external adversity that has characterized the politics of the central state since the 1989 Islamist revolution. Two inter-related political trajectories of China’s Sudan engagement are examined here. The first concerns Beijing’s relations with the ruling National Congress party in incorporating China into its domestic politics and foreign relations amidst war in Darfur, to which Beijing has responded through a more engaged political role. The second confronts the practical limitations of China’s sovereignty doctrine and exclusive reliance upon relations with the central state. Following the peace agreement of 2005 that ended the North–South war, and motivated by political imperatives linked to investment protection concerns, China has developed new relations with the semi-autonomous Government of Southern Sudan, thus seeking to position itself to navigate Sudan’s uncertain political future
Ecophysiology of Kuwaiti macroalgae with special emphasis on temperature and salinity tolerance related to the conditions at desalination plant outfalls
ACKNOWLEDGEMENTS The present work is part of the PhD thesis 'Macroalgal biodiversity of Kuwait, with special emphasis on the vicinity of desalination plants' of Amal H. Hajiya Hasan. We acknowledge the technical assistance of Dr. Hedda Weitz and Mr Mohamed Elgamily for ArcGIS assistance. We acknowledge the funding received to support this work from the Marine Alliance for Science and Technology (grant reference HR09011) to FCK and Kuwait Foundation for the Advancement of Science (KFAS; grant number PR1712SL18) to DA.Peer reviewedPostprin
Global patterns of the double mutualism phenomenon
This is the author accepted manuscript. The final version is available from Wiley via the DOI in this recordData deposition: Data available from the Dryad Digital Repository: (Fuster et al. 2018).A double mutualism (DM) occurs when two interacting species benefit each other in two different functions, e.g. when an animal species acts both as pollinator and seed disperser of the same plant. Besides the double benefit, a DM also imposes a larger risk to both functions if the performance of one partner declines. We conducted the first global review of DMs involving pollinators and seed dispersers, aiming to: 1) assess their prevalence across ecosystems and biogeographical regions; 2) identify the main plant and animal taxa, and their traits, implicated in DMs; and 3) evaluate the conservation status of double mutualist species. We compiled published and unpublished DM records using specific search terms, noting the species involved, their conservation status and geographic location, as well as the type of study (species vs community‐level) in which the DM was detected. We identified 302 DM cases involving 207 plant and 92 animal species from 16 mainland and 17 island areas. Most records come from tropical regions and islands. Animals included birds (62%), mammals (22%), and reptiles (16%), mostly opportunist species; only 18% were nectarivores. Plants were mainly fleshy‐fruited shrub or tree species (59%) with actinomorphic flowers that were visited by several or many pollinator species (87%). Most (56%) DMs were detected in community‐level studies. DMs are mostly prevalent in ecosystems with limited food resources and mutualist partners, and with high generalization levels. Nearly 30% of the species involved in DMs are threatened according to IUCN criteria, 68% of which are found on islands. The high prevalence of DM on islands paired with the threat status of island species suggest that the loss of a double mutualists and its cascading consequences may have a severe impact on community composition and functioning of fragile island ecosystems.Spanish Governmen
A monolithic resonant terahertz sensor element comprising a metamaterial absorber and micro-bolometer
In this article a monolithic resonant terahertz sensor element with a noise equivalent power superior to that of typical commercial room temperature single pixel terahertz detectors and capable of close to real time read-out rates is presented. The detector is constructed via the integration of a metamaterial absorber and a micro-bolometer sensor. An absorption magnitude of 57% at 2.5 THz, a minimum NEP of inline image and a thermal time constant of 68 ms for the sensor are measured. As a demonstration of detector capability, it is employed in a practical Nipkow terahertz imaging system. The monolithic resonant terahertz detector is readily scaled to focal plane array formats by adding standard read-out and addressing circuitry enabling compact, low-cost terahertz imaging
Efficient synthesis of 2,5-dicarbonyl derivatives of 3,4-ethylenedithiothiophene (EDTT) via addition-elimination reaction
Derivatives of 3,4-ethylenedithiothiophene (EDTT) are reported starting from tetrabromothiophene. Selective 2,5-dilithiation followed by reaction with a range of aldehydes gives diols as mixtures of diastereomers. Only the 2 and 5 positions in thiophene react leaving the 3,4-bromides for further elaboration. The diols are oxidised to their corresponding diketones using activated MnO2. Reaction with 1,2-ethanedithiol, by addition-elimination, provides access to novel monomers for the preparation of conjugated copolymers of 3,4-ethylenedithiothiophene (EDTT). A range of these monomers can be attained by applying the synthesis of a series of ketones applicable to further synthesis of ?-extended thiophene-based organic semiconductors. Finally, this new route was compared to 3,4-ethylenedioxythiophene (EDOT) dialdehyde derivatives synthesised by an alternative to literature chemistry
Assessment of the macroalgal diversity of Kuwait by using the Germling Emergence Method
ACKNOWLEDGEMENTS The present work formed part of the first author’s PhD thesis 'Macroalgal biodiversity of Kuwait, with special emphasis on the vicinity of desalination plants'. We acknowledge Dr. Hedda Weitz (University of Aberdeen) for providing help in the laboratory and from Ioanna Kosma (University of the Aegean) and Andreas Henkel (Kuwait University) for diving and logistics support during the expedition to Kuwait. We acknowledge the funding received to support this work from the Marine Alliance for Science and Technology (grant reference HR09011) to FCK and Kuwait Foundation for the Advancement of Science (KFAS; grant number PR17125L18) to DA. To Mr. Yusuf Buhadi from the Department of Marine Sciences at Kuwait University for his help in the field work and to Mrs. Nisha V. S. Vadakkhancheril for photographyPeer reviewedPublisher PD
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