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Here we present the synthesis of porous platinum–palladium macrobeams templated from high aspect ratio Magnus’ salt needle derivatives. The combination of [PtCl4]2− and/or [PdCl4]2− with [Pt(NH3)4]2+ ions results in salt needles ranging from 15 to 300 µm in length. Electrochemical reduction of the salt templates results in porous macrobeams with a square cross-section. Porous side wall texture and elemental composition was controlled with initial platinum to palladium salt ratio. Macrobeam free-standing films exhibited a specific capacitance up to 11.73 F/g and a solvent accessible surface area of 26.6 m2/g. These salt-templated porous platinum–palladium macrobeams offer a promising material for fuel cell catalysis.
Gary P. Baker, Research Associate at the University of East Anglia, and a Researcher at the University of Groningen in the Netherlands.,
Craig L. Lambert, Lecturer in Maritime History at the University of Southampton.,
David Simpkin, Teacher of History at Birkenhead Sixth-Form College.,
J. J. N. Palmer
Given the contribution Andrew Ayton has made to the study of late medieval military history we hope he is not surprised by the production of a Festschrift in his honour. All the editors of this volume were supervised by Andrew for their doctoral studies, and all no doubt thrashed out the general outlines to their theses in one of the infamous ‘Ayton’ meetings that regularly ran into the late evening. Andrew's enthusiasm for his subject was infectious and it is to his credit that many of his former students have gone on to publish contributions on late medieval military and naval history. The papers featured in the present volume highlight the important international impact Andrew's work has had on his students and academic colleagues.
Andrew, a native of Dorset, is in his own words ‘a country dweller at heart’ but has spent much of his working life in the big city. He studied as an undergraduate at the University of Hull in the early 1980s, during which time he undertook several modules taught by Professor John Palmer. John's module on the Hundred Years’ War in particular seems to have kindled Andrew's interest in medieval military history and military communities; it certainly began a fruitful association between two like-minded scholars which was to span some three decades until John's retirement in 2002. Andrew often visited John's home to discuss their latest research and he will be pleased to know he is remembered with some affection by John's children.
After graduating, Andrew spent a brief spell in a ‘real’ job, before returning to Hull to study for his Ph.D. under John Palmer – ‘The Warhorse and Military Service under Edward III’ – and from 1985 to 1987 Andrew was employed, alongside Virginia Davis, on John's Domesday Project. This was a role for which Andrew was particularly well equipped. He had taken John Palmer's special subject on the Domesday Book as an undergraduate, which had provided him with the essential background plus the basic computing skills – in particular related to databases – needed for the research: rare qualifications in the mid-1980s. This period, of course, included the 900th anniversary of Domesday Book, which for Andrew and Virginia entailed a frenetic year, giving lectures and demonstrations around the UK while trying to keep to a research schedule and do some work on their own account.
Whether monozygotic (MZ) and dizygotic (DZ) twins differ from each other in a variety of phenotypes is important for genetic twin modeling and for inferences made from twin studies in general. We analyzed whether there were differences in individual, maternal and paternal education between MZ and DZ twins in a large pooled dataset. Information was gathered on individual education for 218,362 adult twins from 27 twin cohorts (53% females; 39% MZ twins), and on maternal and paternal education for 147,315 and 143,056 twins respectively, from 28 twin cohorts (52% females; 38% MZ twins). Together, we had information on individual or parental education from 42 twin cohorts representing 19 countries. The original education classifications were transformed to education years and analyzed using linear regression models. Overall, MZ males had 0.26 (95% CI [0.21, 0.31]) years and MZ females 0.17 (95% CI [0.12, 0.21]) years longer education than DZ twins. The zygosity difference became smaller in more recent birth cohorts for both males and females. Parental education was somewhat longer for fathers of DZ twins in cohorts born in 1990–1999 (0.16 years, 95% CI [0.08, 0.25]) and 2000 or later (0.11 years, 95% CI [0.00, 0.22]), compared with fathers of MZ twins. The results show that the years of both individual and parental education are largely similar in MZ and DZ twins. We suggest that the socio-economic differences between MZ and DZ twins are so small that inferences based upon genetic modeling of twin data are not affected.
To describe the epidemiology of complex surgical site infection (SSI) following commonly performed surgical procedures in community hospitals and to characterize trends of SSI prevalence rates over time for MRSA and other common pathogens
We prospectively collected SSI data at 29 community hospitals in the southeastern United States from 2008 through 2012. We determined the overall prevalence rates of SSI for commonly performed procedures during this 5-year study period. For each year of the study, we then calculated prevalence rates of SSI stratified by causative organism. We created log-binomial regression models to analyze trends of SSI prevalence over time for all pathogens combined and specifically for MRSA.
A total of 3,988 complex SSIs occurred following 532,694 procedures (prevalence rate, 0.7 infections per 100 procedures). SSIs occurred most frequently after small bowel surgery, peripheral vascular bypass surgery, and colon surgery. Staphylococcus aureus was the most common pathogen. The prevalence rate of SSI decreased from 0.76 infections per 100 procedures in 2008 to 0.69 infections per 100 procedures in 2012 (prevalence rate ratio [PRR], 0.90; 95% confidence interval [CI], 0.82–1.00). A more substantial decrease in MRSA SSI (PRR, 0.69; 95% CI, 0.54–0.89) was largely responsible for this overall trend.
The prevalence of MRSA SSI decreased from 2008 to 2012 in our network of community hospitals. This decrease in MRSA SSI prevalence led to an overall decrease in SSI prevalence over the study period.
To determine the association (1) between shorter operative duration and surgical site infection (SSI) and (2) between surgeon median operative duration and SSI risk among first-time hip and knee arthroplasties.
Retrospective cohort study
A total of 43 community hospitals located in the southeastern United States.
Adults who developed SSIs according to National Healthcare Safety Network criteria within 365 days of first-time knee or hip arthroplasties performed between January 1, 2008 and December 31, 2012.
Log-binomial regression models estimated the association (1) between operative duration and SSI outcome and (2) between surgeon median operative duration and SSI outcome. Hip and knee arthroplasties were evaluated in separate models. Each model was adjusted for American Society of Anesthesiology score and patient age.
A total of 25,531 hip arthroplasties and 42,187 knee arthroplasties were included in the study. The risk of SSI in knee arthroplasties with an operative duration shorter than the 25th percentile was 0.40 times the risk of SSI in knee arthroplasties with an operative duration between the 25th and 75th percentile (risk ratio [RR], 0.40; 95% confidence interval [CI], 0.38–0.56; P<.01). Short operative duration did not demonstrate significant association with SSI for hip arthroplasties (RR, 1.04; 95% CI, 0.79–1.37; P=.36). Knee arthroplasty surgeons with shorter median operative durations had a lower risk of SSI than surgeons with typical median operative durations (RR, 0.52; 95% CI, 0.43–0.64; P<.01).
Short operative durations were not associated with a higher SSI risk for knee or hip arthroplasty procedures in our analysis.
Infect. Control Hosp. Epidemiol. 2015;36(12):1431–1436
A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), and included 842,951 height and BMI measurements from twins aged 1 to 102 years. The results showed that DZ twins were consistently taller than MZ twins, with differences of up to 2.0 cm in childhood and adolescence and up to 0.9 cm in adulthood. Similarly, a greater mean BMI of up to 0.3 kg/m2 in childhood and adolescence and up to 0.2 kg/m2 in adulthood was observed in DZ twins, although the pattern was less consistent. DZ twins presented up to 1.7% greater height and 1.9% greater BMI than MZ twins; these percentage differences were largest in middle and late childhood and decreased with age in both sexes. The variance of height was similar in MZ and DZ twins at most ages. In contrast, the variance of BMI was significantly higher in DZ than in MZ twins, particularly in childhood. In conclusion, DZ twins were generally taller and had greater BMI than MZ twins, but the differences decreased with age in both sexes.
For over 100 years, the genetics of human anthropometric traits has attracted scientific interest. In particular, height and body mass index (BMI, calculated as kg/m2) have been under intensive genetic research. However, it is still largely unknown whether and how heritability estimates vary between human populations. Opportunities to address this question have increased recently because of the establishment of many new twin cohorts and the increasing accumulation of data in established twin cohorts. We started a new research project to analyze systematically (1) the variation of heritability estimates of height, BMI and their trajectories over the life course between birth cohorts, ethnicities and countries, and (2) to study the effects of birth-related factors, education and smoking on these anthropometric traits and whether these effects vary between twin cohorts. We identified 67 twin projects, including both monozygotic (MZ) and dizygotic (DZ) twins, using various sources. We asked for individual level data on height and weight including repeated measurements, birth related traits, background variables, education and smoking. By the end of 2014, 48 projects participated. Together, we have 893,458 height and weight measures (52% females) from 434,723 twin individuals, including 201,192 complete twin pairs (40% monozygotic, 40% same-sex dizygotic and 20% opposite-sex dizygotic) representing 22 countries. This project demonstrates that large-scale international twin studies are feasible and can promote the use of existing data for novel research purposes.
Many species of marine sponges on tropical reefs host abundant and diverse symbiont communities capable of varied metabolic pathways. While such communities may confer a nutritional benefit to some hosts (termed High Microbial Abundance (HMA) sponges), other sympatric species host only sparse symbiont communities (termed Low Microbial Abundance (LMA) sponges) and obtain a majority of their C and N from local sources. Sponge communities are widespread across large latitudinal gradients, however, and recent evidence suggests that these symbioses may also extend beyond the tropics. We investigated the role that symbionts play in the ecology of sponges from the temperate, hard-bottom reefs of Gray's Reef National Marine Sanctuary by calculating the niche size (as standard ellipse area (SEAc)) and assessing the relative placement of five HMA and four LMA sponge species within bivariate (δ13C and δ15N) isotopic space. Although photosymbiont abundance was low across most of these species, sponges were widespread across isotopic niche space, implying that microbial metabolism confers an ecological benefit to temperate sponges by expanding host metabolic capability. To examine how these associations vary across a latitudinal gradient, we also compared the relative placement of temperate and tropical conspecifics within isotopic space. Surprisingly, shifts in sponge δ13C and δ15N values between these regions suggest a reduced reliance on symbiont-derived nutrients in temperate sponges compared with their tropical conspecifics. Despite this, symbiotic sponges in temperate systems likely have a competitive advantage, allowing them to grow and compete for space within these habitats.
In North America, terrestrial records of biodiversity and climate change that span Marine Oxygen Isotope Stage (MIS) 5 are rare. Where found, they provide insight into how the coupling of the ocean–atmosphere system is manifested in biotic and environmental records and how the biosphere responds to climate change. In 2010–2011, construction at Ziegler Reservoir near Snowmass Village, Colorado (USA) revealed a nearly continuous, lacustrine/wetland sedimentary sequence that preserved evidence of past plant communities between ~140 and 55 ka, including all of MIS 5. At an elevation of 2705 m, the Ziegler Reservoir fossil site also contained thousands of well-preserved bones of late Pleistocene megafauna, including mastodons, mammoths, ground sloths, horses, camels, deer, bison, black bear, coyotes, and bighorn sheep. In addition, the site contained more than 26,000 bones from at least 30 species of small animals including salamanders, otters, muskrats, minks, rabbits, beavers, frogs, lizards, snakes, fish, and birds. The combination of macro- and micro-vertebrates, invertebrates, terrestrial and aquatic plant macrofossils, a detailed pollen record, and a robust, directly dated stratigraphic framework shows that high-elevation ecosystems in the Rocky Mountains of Colorado are climatically sensitive and varied dramatically throughout MIS 5.
Emergency Medical Services (EMS) providers face many ethical issues while providing prehospital care to children and adults. Although provider judgment plays a large role in the resolution of conflicts at the scene, it is important to establish protocols and policies, when possible, to address these high-risk and complex situations. This article describes some of the common situations with ethical underpinnings encountered by EMS personnel and managers including denying or delaying transport of patients with non-emergency conditions, use of lights and sirens for patient transport, determination of medical futility in the field, termination of resuscitation, restriction of EMS provider duty hours to prevent fatigue, substance abuse by EMS providers, disaster triage and difficulty in switching from individual care to mass-casualty care, and the challenges of child maltreatment recognition and reporting. A series of ethical questions are proposed, followed by a review of the literature and, when possible, recommendations for management.
BeckerTK, Gausche-HillM, AsweganAL, BakerEF, BookmanKJ, BradleyRN, De LorenzoRA, SchoenwetterDJ for the American College of Emergency Physicians’ EMS Committee. Ethical Challenges in Emergency Medical Services: Controversies and Recommendations. Prehosp Disaster Med. 2013;28(5):1-10.
Background: While smoking rates in the United States have decreased, some population subgroups have smoking rates that exceed national and state averages. These higher rates often are associated with higher incidence rates of tobacco-associated cancers. Over time, a decrease in smoking rates leads to lower cancer incidence. Methods: Using spatial modelling techniques, we identified an underserved geographic locale in South Florida with higher than expected incidence rates of tobacco-associated cancers. We then used a community-based participatory research (CBPR) design to conduct focus groups in 2011 to elicit information about the acceptability of a smoking cessation intervention delivered by trained former smokers from within peer networks. Results: A variety of smoking cessation strategies was presented and discussed in separate, gender-stratified focus groups comprised of former and current smokers (n = 39). Focus group findings consistently indicated that support groups were the preferred cessation mechanism in this community. Based on this finding, we changed our initially proposed cessation approach to one which employed support groups as a quit method. Conclusions: Currently, we are collecting pilot data to test this intervention and to reach smokers who might not otherwise be directly targeted with cessation messaging from larger tobacco control initiatives. If successful, this strategy can be adapted to effect other important changes in health behaviours in at-risk populations.
Background: People with dementia have a range of needs that are met by informal caregivers. A DVD-based training program was developed using research-based strategies for memory and communication in dementia. The effectiveness of the training on the caregiver experience and the well-being of the person with dementia was evaluated.
Methods: A pre-test/post-test controlled trial was undertaken with caregiver–care-recipient dyads living in the community. Measures of the carers’ knowledge of memory and communication strategies, burden, positive perceptions of caregiving, and perceptions of problem behaviors were taken pre- and three months post-intervention. The depression and well-being of the person with dementia were also evaluated. Satisfaction with the training and feedback were measured.
Results: Twenty-nine dyads (13 training group, 16 control group) participated. Bonferroni's correction was made to adjust for multiple comparisons, setting α at 0.00385. A significant improvement was found in caregivers’ knowledge for the training group compared to the control group (p = 0.0011). The training group caregivers reported a reduction in the frequency of care recipient disruptive behaviors (p = 0.028) and increased perceptions of positive aspects of caregiving (p = 0.039), both at a level approaching significance. The training group care recipients had increased frequency of verbally communicated depressive behaviors at a level approaching significance (p = 0.0126). The frequency of observed depressive behaviors was not significantly different between groups.
Conclusions: This approach to training for caregivers of people with dementia appears promising for its impact on knowledge and the caregiving experience. Further research could monitor the impact of the training on broader measures of depression and well-being, with a larger sample.