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Escherichia coli O157 are zoonotic bacteria for which cattle are an important reservoir. Prevalence estimates for E. coli O157 in British cattle for human consumption are over 10 years old. A new baseline is needed to inform current human health risk. The British E. coli O157 in Cattle Study (BECS) ran between September 2014 and November 2015 on 270 farms across Scotland and England & Wales. This is the first study to be conducted contemporaneously across Great Britain, thus enabling comparison between Scotland and England & Wales. Herd-level prevalence estimates for E. coli O157 did not differ significantly for Scotland (0·236, 95% CI 0·166–0·325) and England & Wales (0·213, 95% CI 0·156–0·283) (P = 0·65). The majority of isolates were verocytotoxin positive. A higher proportion of samples from Scotland were in the super-shedder category, though there was no difference between the surveys in the likelihood of a positive farm having at least one super-shedder sample. E. coli O157 continues to be common in British beef cattle, reaffirming public health policy that contact with cattle and their environments is a potential infection source.
Population-based registries report 95% 5-year survival for children undergoing surgery for CHD. This study investigated paediatric cardiac surgical outcomes in the Australian indigenous population.
All children who underwent cardiac surgery between May, 2008 and August, 2014 were studied. Demographic information including socio-economic status, diagnoses and co-morbidities, and treatment and outcome data were collected at time of surgery and at last follow-up.
A total of 1528 children with a mean age 3.4±4.6 years were studied. Among them, 123 (8.1%) children were identified as indigenous, and 52.7% (62) of indigenous patients were in the lowest third of the socio-economic index compared with 28.2% (456) of non-indigenous patients (p⩽0.001). The indigenous sample had a significantly higher Comprehensive Aristotle Complexity score (indigenous 9.4±4.2 versus non-indigenous 8.7±3.9, p=0.04). The probability of having long-term follow-up did not differ between groups (indigenous 93.8% versus non-indigenous 95.6%, p=0.17). No difference was noted in 30-day mortality (indigenous 3.2% versus non-indigenous 1.4%, p=0.13). The 6-year survival for the entire cohort was 95.9%. The Cox survival analysis demonstrated higher 6-year mortality in the indigenous group – indigenous 8.1% versus non-indigenous 5.0%; hazard ratio (HR)=2.1; 95% confidence intervals (CI): 1.1, 4.2; p=0.03. Freedom from surgical re-intervention was 79%, and was not significantly associated with the indigenous status (HR=1.4; 95% CI: 0.9, 1.9; p=0.11). When long-term survival was adjusted for the Comprehensive Aristotle Complexity score, no difference in outcomes between the populations was demonstrated (HR=1.6; 95% CI: 0.8, 3.2; p=0.19).
The indigenous population experienced higher late mortality. This apparent relationship is explained by increased patient complexity, which may reflect negative social and environmental factors.
Mental health problems are inseparable from the environment. With virtual reality (VR), computer-generated interactive environments, individuals can repeatedly experience their problematic situations and be taught, via evidence-based psychological treatments, how to overcome difficulties. VR is moving out of specialist laboratories. Our central aim was to describe the potential of VR in mental health, including a consideration of the first 20 years of applications. A systematic review of empirical studies was conducted. In all, 285 studies were identified, with 86 concerning assessment, 45 theory development, and 154 treatment. The main disorders researched were anxiety (n = 192), schizophrenia (n = 44), substance-related disorders (n = 22) and eating disorders (n = 18). There are pioneering early studies, but the methodological quality of studies was generally low. The gaps in meaningful applications to mental health are extensive. The most established finding is that VR exposure-based treatments can reduce anxiety disorders, but there are numerous research and treatment avenues of promise. VR was found to be a much-misused term, often applied to non-interactive and non-immersive technologies. We conclude that VR has the potential to transform the assessment, understanding and treatment of mental health problems. The treatment possibilities will only be realized if – with the user experience at the heart of design – the best immersive VR technology is combined with targeted translational interventions. The capability of VR to simulate reality could greatly increase access to psychological therapies, while treatment outcomes could be enhanced by the technology's ability to create new realities. VR may merit the level of attention given to neuroimaging.
We compare the results of using a Random Forest Classifier with the results of using Nonparametric Discriminant Analysis to classify whether a filament channel (in the case of a filament eruption) or an active region (in the case of a flare) is about to produce an event. A large number of descriptors are considered in each case, but it is found that only a small number are needed in order to get most of the improvement in performance over always predicting the majority class. There is little difference in performance between the two classifiers, and neither results in substantial improvements over simply predicting the majority class.
De novo interictal psychosis, albeit uncommon, can develop in patients following temporal lobe surgery for epilepsy. Pathological alterations of the dentate gyrus, including cytoarchitectural changes, immaturity and axonal reorganization that occur in epilepsy, may also underpin co-morbid psychiatric disorders. Our aim was to study candidate pathways that may be associated with the development of interictal psychosis post-operatively in patients with hippocampal sclerosis (HS).
A total of 11 patients with HS who developed interictal psychosis (HS-P) post-operatively were compared with a matched surgical HS group without psychosis (HS-NP). Resected tissues were investigated for the extent of granule cell dispersion, mossy fibre sprouting and calbindin expression in the granule cells. We quantified doublecortin, mini-chromosome maintenance protein 2 (MCM2) and reelin-expressing neuronal populations in the dentate gyrus as well as the distribution of cannabinoid type 1 receptor (CBR1).
The patterns of neuronal loss and gliosis were similar in both groups. HS-P patients demonstrated less mossy fibre sprouting and granule cell dispersion (p < 0.01) and more frequent reduction in calbindin expression in granule cells. There were no group differences in the densities of immature MCM2, doublecortin and reelin-positive cells. CBR1 labelling was significantly lower in Cornu ammonis area CA4 relative to other subfields (p < 0.01); although reduced staining in all hippocampal regions was noted in HS-P compared with HS-NP patients, the differences were not statistically significant.
The alterations in dentate gyrus pathology found in HS-P patients could indicate underlying differences in the cellular response to seizures. These mechanisms may predispose to the development of psychosis in epilepsy and warrant further investigation.
In this study, the authors focused on children from 2-8 years of age and asked the simple question: what do engineers do? The number one response was: “I don’t know”, the number two response was “they drive a train.” While children are very familiar with professionals such as doctors, teachers, nurses, firefighters and policemen, they are rarely introduced to engineers. With this motivation, the authors developed a novel children’s book on engineering: Engineering Elephants. This book is an outreach tool that introduces children to the dynamic world of engineering design through roller coasters, fireworks, and a plethora of other exciting adventures. The book teaches children about relevant topics such as nanotechnology, renewable energy, and prosthetics by engaging them through an interactive journey of an elephant and his questioning of the world around him. The text was strategically developed using the language of science (asking questions) and introducing vocabulary relevant to science and math using a lyrical pattern. This presentation will highlight the development of this book as an instructional aid but also detail the response of various age groups to engineering activities presented as a companion to this book. In particular, an elementary school district in West Texas designed a 4-5th grade 3-week summer school curriculum around this book. Results from this study will have an impact on future generations by inspiring them to consider the exciting profession of engineering at an early age.
The field of neuroscience draws together many disciplines in the study of the nervous system and the properties of mind. Although understanding the basic structure and physiology of the brain and its processes has led to high-impact findings, it is typically the manipulation or application of this knowledge that is most interesting to individuals outside the scientific community. The development and use of neurotechnologies, those tools and devices that interact with and modulate the nervous system, is a fast-emerging area of technical achievement that has vast potential to impact our understanding of, and interaction with the brain. The rapidly growing field of neurotechnology research and development employs knowledge and tools from diverse fields. It is through interdisciplinary, collaborative thinking that great advances have been made to develop, research, and transfer neurotechnology to the clinic and beyond. Such technologies include functional magnetic resonance imaging (fMRI), electroencephalography (EEG), functional near-infrared spectroscopy (fNIRS), deep brain stimulation (DBS), and neural prosthetics. Investigation into the mechanisms and functions of the brain is leading to a vastly improved understanding of brain disease, injuries, human cognition, and behavior, and will give us an unprecedented ability to heal, enhance, and manipulate the nervous system.
Many ethical, legal, and social implications (ELSI) of these technologies and their identified and potential uses have emerged, with others still to surface, as the scientific community and general public have increasing access to medical and commercial neurotechnologies (Eaton & Illes 2007).
About 2·3% (16/700) of faecal specimens from renal transplant recipients and patients having home haemodialysis as well as patients attending their general practitioners with symptoms of gastroenteritis yielded Listeria species 40% of positive faeces contained more than one Listeria species or serovar. The proportion of positive specimens was similar in all three patient groups. Listeria were isolated from 5·6% (10/177) of renal transplant recipients on one or more occasions over the period of a year. The commonest species was L. monocytogenes and type 4b the commonest serovar. Carriage was more common in July and August than other times of year, and less than 28 weeks in duration. In renal transplant recipients carriage was positively related to treatment with ranitidine, consumption of more than three types of cheese in the previous 20 months, and consumption of English cheddar cheese more than once per week.
Stochastic Efficiency with Respect to a Function (SERF) is used to rank transgenic cotton technology groups and place an upper and lower bound on their value. Yield and production data from replicated plot experiments are used to build cumulative distribution functions of returns for nontransgenic, Roundup Ready, Bollgard, and stacked gene cotton cultivars. Analysis of Arkansas data indicated that the stacked gene and Roundup Ready technologies would be preferred by a large number of risk neutral and risk averse producers as long as the costs of the technology and seed are below the lower bounds calculated in this manuscript.
The techniques currently used by most specialist centres for magnetic resonance (MR) imaging of the fetus were developed in the 1990s, when fast imaging sequences capable of good soft tissue contrast were introduced. Earlier pioneering work on fetal MR imaging in the early 1980s revealed some promise for this application, but at the time it was not generally considered of diagnostic quality or clinical practicality because of the long acquisition times and inevitable image degradation resulting from fetal movement, problems which were overcome only by means of maternal sedation or neuromuscular blockade of the fetus. As with the early development of MR imaging in general, it is the ability to image central nervous system (CNS) tissues with a clarity and contrast far exceeding X-ray computed tomography and ultrasound that has shown the most benefit to date. Subsequent development of techniques for specific problem solving in other areas of the body will undoubtedly follow.
Norway rats (Rattus norvegicus) carry several zoonotic pathogens and because rats and humans live in close proximity in urban environments, there exists potential for transmission. To identify zoonotic agents carried by rats in Baltimore, Maryland, USA, we live-trapped 201 rats during 2005–2006 and screened them for a panel of viruses, bacteria, and parasites. Antibodies against Seoul virus (57·7%), hepatitis E virus (HEV, 73·5%), Leptospira interrogans (65·3%), Bartonella elizabethae (34·1%), and Rickettsia typhi (7·0%) were detected in Norway rats. Endoparasites, including Calodium hepatica (87·9%) and Hymenolepis sp. (34·4%), and ectoparasites (13·9%, primarily Laelaps echidninus) also were present. The risk of human exposure to these pathogens is a significant public health concern. Because these pathogens cause non-specific and often self-limiting symptoms in humans, infection in human populations is probably underdiagnosed.
Relatively little is known about the relationship of most personality disorders to executive cognitive functioning despite their associations with frontal cortex activity. Research on genetic influence is lacking for most personality disorders, and research on genetic influences associated with executive cognitive functioning is sparse and mixed. The Florida State Twin Registry was created to conduct a pilot twin study aimed at examining genetic influence on personality disorders and executive cognitive functioning. Measures included structured clinical interviews for symptoms and diagnoses of personality disorders (borderline, histrionic, narcissistic, antisocial, obsessive–compulsive, avoidant, and dependent), depression, substance abuse/dependence, anxiety disorders, and eating disorders. The Wisconsin Card Sorting Test and the Stroop Color-Word Test were administered to assess executive cognitive functioning. Self-report questionnaires were included to assess maladaptive personality traits. Data sharing and future directions for growing the Florida State Twin Registry are discussed.
Studies on strontium-doped lead zirconate titanate (PSZT) have been reported for its high piezoelectric and ferroelectric properties. For PSZT to exhibit pronounced piezoelectric behaviour it must have a crystalline grain structure (perovskite orientation). This paper is a study of the deposition of PSZT thin films by RF magnetron sputtering and the effect of cooling rate, after deposition at temperatures between 500 °C and 700 °C. X-Ray Diffraction (XRD) results are used to show how a cooling rate of 5 °C/min increases the degree of perovskite orientation in sputtered films, when compared to a cooling rate of 15 °C/min. The absence of significant shifts in the positions of diffraction peak patterns in XRD results are used to demonstrate low stress in the deposited films. Atomic Force Microscope (AFM) imaging is used to show the crystalline nature of the PSZT thin films.
This paper examines the fate of alleles and changes of genetic diversity in old (ca 1930s) versus more modern (ca 1990s) UK bread wheat varieties using 14 mapped DNA microsatellite (simple sequence repeat, SSR) loci and morphological markers. The allelic constitution of varieties belonging to three time periods (early, intermediate, late) was determined. While at certain loci one or more SSR alleles were gained between early and late periods, at others the allelic representation remained constant, although a shift in allelic frequencies could sometimes be detected. No locus showed a clear, net loss in the total number of alleles over the time period. In a further group of loci, there was neither clear gain nor loss, but rather a dynamic flux of alleles. A comparison of the allelic constitution of the UK variety set with a larger genetic pool (non-UK varieties) showed that some loci were rather similar in allelic constitution, while others possessed additional diversity. Certain SSR alleles appeared to be associated with old or modern varieties, possibly indicating associations with chromosome regions under selection pressure. The same exercise was conducted on the basis of 14 of the morphological characteristics recorded in the course of distinctness, uniformity and stability testing of varieties. Overall, this analysis generated a similar picture of changes in diversity to that obtained from the microsatellite data.
Active nitrogen species produced by an Oxford Applied Research HD-25 plasma source have been monitored by optical emission spectroscopy and quadrapole mass spectroscopy. Both techniques confirmed that at higher RF powers and lower flow rates the efficiency of atomic nitrogen production increased; emission spectroscopy confirmed that this was at the expense of active molecular nitrogen (N2*). InN films grown on (0001) sapphire/GaN with higher relative molecular content were found to have lower carrier concentrations than the corresponding films grown with higher atomic content. However, electrical properties of films grown on (111) YSZ showed insensitivity to the active nitrogen content. Etching experiments revealed that films grown on sapphire/GaN were nitrogen-polar, while films grown on YSZ were In-polar, suggesting that film polarity can greatly influence the effect active species have on growth. Lattice relaxation, as measured by reflection high-energy electron diffraction, revealed that the N-polar films grown under high relative molecular flux relaxed fully after ∼60 nm of growth, while the corresponding In-polar film relaxed fully within the first several nm of growth.
The morphology of insect eyes often seems to be shaped by evolution to match their behaviour and lifestyle. Here the relationship between the nuptial flight behaviour of 10 Atta species (Hymenoptera: Formicidae) and the eye size of male and female alates, including the compound eyes, ommatidia facets, and ocelli were examined. These species can be divided into two distinct groups by nuptial flight behaviour: those that initiate the nuptial flight during the day and those that initiate it at night. The most striking difference between day- vs night-flying alates was in ocellus area, which was almost 50% larger in night-flying species. Night-flying species also had significantly larger ommatidia facets than day-flying species. A scaling relationship was also found between compound eye area, facet diameter, and ocellus area vs overall body size. Detailed observations are also presented on the nuptial flight behaviour of a night- vs day-flying species, A. texana and A. sexdens, respectively. The pattern in A. texana is for a single large and precisely timed nuptial flight before dawn, while flights of A. sexdens last for several hours, beginning at midday. Further observations suggest that the timing of the nuptial flight in A. texana is easily disrupted by light pollution.
A novel method for forming interdigitated electrodes for GHz Surface acoustic wave (SAW) devices on diamond using a damascene-like polishing technique is described. Low aspect ratio Al electrodes are recessed into the diamond substrates to create a near planar surface. This allows the deposition of higher quality oriented ZnO. CVD diamond samples were ion-beam etched with groove widths in the range 1-5μm to a depth of 80-120nm. Al (120nm thick) was sputter deposited on to the etched diamond and was polished using either (i) a solution of 0.05μm silica on a neoprene polishing cloth or (ii) using a ∼0.12mm thick PVDF (polyvinylidene difluoride) filter pad with colloidal solutions of silica. Using AFM scans and optical microscopy it was observed that the combination of method (i) with the small sample size resulted in significant hollowing-out of the Al electrodes and complete removal of Al from over 90% of the pad-interconnect area. The alternative technique in (ii) demonstrated far less Al removal and better uniformity in the electrode patterns.
Several Vigna species were used to determine the role of pod trichomes and pod toughness in the resistance of cowpea to feeding damage by the coreid bug Clavigralla tomentosicollis Stal. The scanning electron microscopy study revealed the presence of glandular and non-glandular trichomes on the pod wall of all test genotypes. The cultivated genotypes TVu 1890, TVu 3354 and IT84S-2246 of the V. unguiculata ssp. unguiculata showed significantly lower (P<0.05) densities of glandular trichomes than accessions of the wild Vigna species (TVnu 72, TVnu 151, and TVnu 707). All pods were similar with respect to the density and length of non-glandular trichomes. The two wild accessions TVnu 151 and TVnu 707 of the V. unguiculata ssp. dekindtiana had low pod, strength similar to that of the susceptible genotype IT84S-2246, and also showed high seed damage levels comparable to that of this susceptible genotype. These accessions of the subspecies dekindtiana contrasted with the wild and resistant accession TVnu 72 of the V. vexillata species which suffered minor seed damage in spite of its low pod strength. The association between high pod strength and low seed damage was found only in the two cultivated genotypes TVu 1890 and TVu 3354. Our results suggest that tough pod wall and high density of glandular trichomes can be combined to achieve enhanced resistance to C. tomentosicollis in cultivated Vigna genotypes.
We evaluated denaturing high pressure liquid chromatography (DHPLC) as a scanning method
for mutation detection in TSC2, and compared it to conformation-sensitive gel electrophoresis
(CSGE) and single-stranded conformation polymorphism analysis (SSCP). The first 20 exons of TSC2
were amplified from 84 TSC patients and screened initially by CSGE and then by DHPLC.
Optimization of DHPLC analysis of each exon was carried out by design of primers with minimum
variation in the melting temperature of the amplicon, and titration of both elution gradient and
temperature. CSGE analysis identified 40 shifts (21 unique) in the 84 patients and 20 exons. All of
these variants were detected by DHPLC, and an additional 27 changes (14 unique) were identified.
Overall 15 of 28 (54%) unique single base substitutions were detected by CSGE; all were detected
by DHPLC. 25 definite or probable mutations were found in these 84 patients (30%) in exons 1–20
of TSC2. In a subsequent blinded analysis of 15 samples with 18 distinct TSC2 sequence variants
originally detected by SSCP in another centre, all variants were detected by DHPLC except one
where the variation occurred within the primer. Ten other (7 unique) sequence variants were
detected in these samples which had not been detected by SSCP. Overall, 11 of 16 (69%) unique
single base substitutions were detected by SSCP; all were detected by DHPLC. We conclude that
DHPLC is superior to both CSGE and SSCP for detection of DNA sequence variation in TSC2,
particularly for single base substitution mutations.