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Seed dispersal is an important ecological process that structures plant communities and influences ecosystem functioning. Loss of animal dispersers therefore poses a serious threat to forest ecosystems, particularly in the tropics where zoochory predominates. A prominent example is the near-total extinction of seed dispersers on the tropical island of Guam following the accidental introduction of the invasive brown tree snake (Boiga irregularis), negatively impacting seedling recruitment and forest regeneration. We investigated frugivory by a remnant population of Såli (Micronesian starling – Aplonis opaca) on Guam and two other island populations (Rota, Saipan) to evaluate their ecological role as a seed disperser in the Mariana archipelago. Using a combination of behavioural observations, nest contents and fecal samples, we documented frugivory of 37 plant species. Native plants comprised the majority (66%) of all species and 90% of all seeds identified in fecal and nest contents. Diet was highly similar across age classes and sampling years. In addition, plant species consumed by Såli comprised 88% of bird-dispersed adult trees and 54% of all adult trees in long-term forest monitoring plots, demonstrating the Såli’s broad diet and potential for restoring native forests. Overall, we provide the most comprehensive assessment to date of frugivory by the Såli and confirm its importance as a seed disperser on Guam and throughout the Marianas.
Describe common pathogens and antimicrobial resistance patterns for healthcare-associated infections (HAIs) that occurred during 2015–2017 and were reported to the Centers for Disease Control and Prevention’s (CDC’s) National Healthcare Safety Network (NHSN).
Data from central line-associated bloodstream infections (CLABSIs), catheter-associated urinary tract infections (CAUTIs), ventilator-associated events (VAEs), and surgical site infections (SSIs) were reported from acute-care hospitals, long-term acute-care hospitals, and inpatient rehabilitation facilities. This analysis included device-associated HAIs reported from adult location types, and SSIs among patients ≥18 years old. Percentages of pathogens with nonsusceptibility (%NS) to selected antimicrobials were calculated for each HAI type, location type, surgical category, and surgical wound closure technique.
Overall, 5,626 facilities performed adult HAI surveillance during this period, most of which were general acute-care hospitals with <200 beds. Escherichia coli (18%), Staphylococcus aureus (12%), and Klebsiella spp (9%) were the 3 most frequently reported pathogens. Pathogens varied by HAI and location type, with oncology units having a distinct pathogen distribution compared to other settings. The %NS for most pathogens was significantly higher among device-associated HAIs than SSIs. In addition, pathogens from long-term acute-care hospitals had a significantly higher %NS than those from general hospital wards.
This report provides an updated national summary of pathogen distributions and antimicrobial resistance among select HAIs and pathogens, stratified by several factors. These data underscore the importance of tracking antimicrobial resistance, particularly in vulnerable populations such as long-term acute-care hospitals and intensive care units.
To describe common pathogens and antimicrobial resistance patterns for healthcare-associated infections (HAIs) among pediatric patients that occurred in 2015–2017 and were reported to the Centers for Disease Control and Prevention’s National Healthcare Safety Network (NHSN).
Antimicrobial resistance data were analyzed for pathogens implicated in central line-associated bloodstream infections (CLABSIs), catheter-associated urinary tract infections (CAUTIs), ventilator-associated pneumonias (VAPs), and surgical site infections (SSIs). This analysis was restricted to device-associated HAIs reported from pediatric patient care locations and SSIs among patients <18 years old. Percentages of pathogens with nonsusceptibility (%NS) to selected antimicrobials were calculated by HAI type, location type, and surgical category.
Overall, 2,545 facilities performed surveillance of pediatric HAIs in the NHSN during this period. Staphylococcus aureus (15%), Escherichia coli (12%), and coagulase-negative staphylococci (12%) were the 3 most commonly reported pathogens associated with pediatric HAIs. Pathogens and the %NS varied by HAI type, location type, and/or surgical category. Among CLABSIs, the %NS was generally lowest in neonatal intensive care units and highest in pediatric oncology units. Staphylococcus spp were particularly common among orthopedic, neurosurgical, and cardiac SSIs; however, E. coli was more common in abdominal SSIs. Overall, antimicrobial nonsusceptibility was less prevalent in pediatric HAIs than in adult HAIs.
This report provides an updated national summary of pathogen distributions and antimicrobial resistance patterns among pediatric HAIs. These data highlight the need for continued antimicrobial resistance tracking among pediatric patients and should encourage the pediatric healthcare community to use such data when establishing policies for infection prevention and antimicrobial stewardship.
Over the past three years, my colleagues and I have embarked on an exciting journey into electric-field control of magnetism, parts of which we describe in this article. What we present to you is something that we believe is extremely exciting from both a fundamental science and applications perspective, and has the potential to revolutionize our world. Needless to say, this will require a lot of new innovations, both in the fundamental science arena as well as translating scientific discoveries into real applications. We hope this article will help spur more research in electric-field control of magnetism within the broad materials community.
Recovery Colleges are opening internationally. The evaluation focus has been on outcomes for Recovery College students who use mental health services. However, benefits may also arise for: staff who attend or co-deliver courses; the mental health and social care service hosting the Recovery College; and wider society. A theory-based change model characterising how Recovery Colleges impact at these higher levels is needed for formal evaluation of their impact, and to inform future Recovery College development. The aim of this study was to develop a stratified theory identifying candidate mechanisms of action and outcomes (impact) for Recovery Colleges at staff, services and societal levels.
Inductive thematic analysis of 44 publications identified in a systematised review was supplemented by collaborative analysis involving a lived experience advisory panel to develop a preliminary theoretical framework. This was refined through semi-structured interviews with 33 Recovery College stakeholders (service user students, peer/non-peer trainers, managers, community partners, clinicians) in three sites in England.
Candidate mechanisms of action and outcomes were identified at staff, services and societal levels. At the staff level, experiencing new relationships may change attitudes and associated professional practice. Identified outcomes for staff included: experiencing and valuing co-production; changed perceptions of service users; and increased passion and job motivation. At the services level, Recovery Colleges often develop somewhat separately from their host system, reducing the reach of the college into the host organisation but allowing development of an alternative culture giving experiential learning opportunities to staff around co-production and the role of a peer workforce. At the societal level, partnering with community-based agencies gave other members of the public opportunities for learning alongside people with mental health problems and enabled community agencies to work with people they might not have otherwise. Recovery Colleges also gave opportunities to beneficially impact on community attitudes.
This study is the first to characterise the mechanisms of action and impact of Recovery Colleges on mental health staff, mental health and social care services, and wider society. The findings suggest that a certain distance is needed in the relationship between the Recovery College and its host organisation if a genuine cultural alternative is to be created. Different strategies are needed depending on what level of impact is intended, and this study can inform decision-making about mechanisms to prioritise. Future research into Recovery Colleges should include contextual evaluation of these higher level impacts, and investigate effectiveness and harms.
. NGC 300 X-1 and IC 10 X-1 are currently the only two robust extragalactic candidates for being Wolf-Rayet/black hole X-ray binaries, the Galactic analogue being Cyg X-3. These systems are believed to be a late product of high-mass X-ray binary evolution and direct progenitors of black hole mergers. From the analysis of Swift data, the orbital period of NGC 300 X-1 was found to be 32.8 h. We here merge the full set of existing data of NGC 300 X-1, using XMM-Newton, Chandra and Swift observations to derive a more precise value of the orbital period of 32.7932 ± 0.0029 h above a confidence level of 99.99%. This allows us to phase connect the X-ray light curve of the source with radial velocity measurements of He II lines performed in 2010. We show that, as for IC 10 X-1 and Cyg X-3, the X-ray eclipse corresponds to maximum of the blueshift of the He II lines, instead of the expected zero velocity. This indicates that for NGC 300 X-1 as well, the wind of the WR star is completely ionised by the black hole radiation and that the emission lines come from the region of the WR star that is in the shadow. We also present for the first time the light curve of two recent very long XMM-Newton observations of the source, performed on the 16th to 20th of December 2016.
Fatigue cracking in polycrystalline NiTi was investigated using a multiscale experimental framework for average grain sizes (GS) from 10 to 1500 nm for the first time. Macroscopic fatigue crack growth rates, measured by optical digital image correlation, were connected to microscopic crack opening and closing displacements, measured by scanning electron microscope DIC (SEM-DIC) using a high-precision external SEM scan controller. Among all grain sizes, the 1500 nm GS sample exhibited the slowest crack growth rate at the macroscale, and the largest crack opening level (stress intensity at first crack opening) and minimum crack opening displacements at the microscale. Smaller GS samples (10, 18, 42, and 80 nm) exhibited nonmonotonic trends in their fatigue performance, yet the correlation was strong between macroscale and microscale behaviors for each GS. The samples that exhibited the fastest crack growth rates (42 and 80 nm GS) showed a small crack opening level and the largest crack opening displacements. The irregular trends in fatigue performance across the nanocrystalline GS samples were consistent with nonmonotonic values in the elastic modulus reported previously, both of which may be related to the presence of residual martensite only evident in the small GS samples (10 and 18 nm).
It is increasingly essential for medical researchers to be literate in statistics, but the requisite degree of literacy is not the same for every statistical competency in translational research. Statistical competency can range from ‘fundamental’ (necessary for all) to ‘specialized’ (necessary for only some). In this study, we determine the degree to which each competency is fundamental or specialized.
We surveyed members of 4 professional organizations, targeting doctorally trained biostatisticians and epidemiologists who taught statistics to medical research learners in the past 5 years. Respondents rated 24 educational competencies on a 5-point Likert scale anchored by ‘fundamental’ and ‘specialized.’
There were 112 responses. Nineteen of 24 competencies were fundamental. The competencies considered most fundamental were assessing sources of bias and variation (95%), recognizing one’s own limits with regard to statistics (93%), identifying the strengths, and limitations of study designs (93%). The least endorsed items were meta-analysis (34%) and stopping rules (18%).
We have identified the statistical competencies needed by all medical researchers. These competencies should be considered when designing statistical curricula for medical researchers and should inform which topics are taught in graduate programs and evidence-based medicine courses where learners need to read and understand the medical research literature.
Giardia duodenalis and Cryptosporidium species are protozoan parasites capable of causing gastrointestinal disease in humans and animals through the ingestion of infective faeces. Whereas Cryptosporidium species can be acquired locally or through foreign travel, there is the mis-conception that giardiasis is considered to be largely travel-associated, which results in differences in laboratory testing algorithms. In order to determine the level of variation in testing criteria and detection methods between diagnostic laboratories for both pathogens across Scotland, an audit was performed. Twenty Scottish diagnostic microbiology laboratories were invited to participate with questions on sample acceptance criteria, testing methods, testing rates and future plans for pathogen detection. Reponses were received from 19 of the 20 laboratories representing each of the 14 territorial Health Boards. Detection methods varied between laboratories with the majority performing microscopy, one using a lateral flow immunochromatographic antigen assay, another using a manually washed plate-based enzyme immunoassay (EIA) and one laboratory trialling a plate-based EIA automated with an EIA plate washer. Whereas all laboratories except one screened every stool for Cryptosporidium species, an important finding was that significant variation in the testing algorithm for detecting Giardia was noted with only four laboratories testing all diagnostic stools. The most common criteria were ‘travel history’ (11 laboratories) and/or ‘when requested’ (14 laboratories). Despite only a small proportion of stools being examined in 15 laboratories for Giardia (2%–18% of the total number of stools submitted), of interest is the finding that a higher positivity rate was observed for Giardia than Cryptosporidium in 10 of these 15 laboratories. These findings highlight that the underreporting of Giardia in Scotland is likely based on current selection and testing algorithms.
Placebo responses raise significant challenges for the design of clinical trials. We report changes in agitation outcomes in the placebo arm of a recent trial of citalopram for agitation in Alzheimer's disease (CitAD).
In the CitAD study, all participants and caregivers received a psychosocial intervention and 92 were assigned to placebo for nine weeks. Outcomes included Neurobehavioral Rating Scale agitation subscale (NBRS-A), modified AD Cooperative Study-Clinical Global Impression of Change (CGIC), Cohen-Mansfield Agitation Inventory (CMAI), the Neuropsychiatric Inventory (NPI) Agitation/Aggression domain (NPI A/A) and Total (NPI-Total) and ADLs. Continuous outcomes were analyzed with mixed-effects modeling and dichotomous outcomes with logistic regression.
Agitation outcomes improved over nine weeks: NBRS-A mean (SD) decreased from 7.8 (3.0) at baseline to 5.4 (3.2), CMAI from 28.7 (6.7) to 26.7 (7.4), NPI A/A from 8.0 (2.4) to 4.9 (3.8), and NPI-Total from 37.3 (17.7) to 28.4 (22.1). The proportion of CGI-C agitation responders ranged from 21 to 29% and was significantly different from zero. MMSE improved from 14.4 (6.9) to 15.7 (7.2) and ADLs similarly improved. Most of the improvement was observed by three weeks and was sustained through nine weeks. The major predictor of improvement in each agitation measure was a higher baseline score in that measure.
We observed significant placebo response which may be due to regression to the mean, response to a psychosocial intervention, natural course of symptoms, or nonspecific benefits of participation in a trial.
A tuberculosis (TB) case was reported May 2008 in Kelowna, British Columbia, leading to a multi-year outbreak in homeless persons. The epidemiological characteristics and social networks of cases are described. Outbreak-related cases were identified from epidemiological information in medical records and from genotyping of TB isolates. Social network information from case interviews were used to identify potential locations of TB transmission, where symptom screening and tuberculin skin testing was conducted. Fifty-two cases that were predominantly male (47/52), Canadian-born (44/50), and were homeless or associated with homeless individuals (42/52) were reported from May 2008 to May 2014. Many isolates (40/49) had partial resistance to isoniazid. Transmission primarily occurred at two homeless shelters, with potential further transmission at sites visited by the general population. TB outbreaks in homeless populations can occur in small, low-incidence cities. Social network information helped prioritize sites for TB screening, thereby improving detection of persons with TB disease or latent infection for treatment.
Cryptosporidium parvum (C. parvum) is one of the most prevalent protozoan pathogens responsible for inducing human and animal disease worldwide. In this study, the glycoprotein-60 (gp60) subtyping tool was employed to assess the molecular diversity of C. parvum from human feces throughout Scotland during potential outbreaks. Over a 24-month period, microscopy analysis revealed 1139 positive feces containing Cryptosporidium species with 256 identified by molecular methods specifically as C. parvum. Cryptosporidium parvum was shown to be more prevalent in rural areas of Scotland and subtyping of 87 isolates demonstrated the predominant family as IIa, which occurred in 94% (n = 82) of isolates. The IIaA15G1R1 subtype was most common, being isolated from 47% (n = 41) of Scottish human cases. Non-IIa strains constituted a total of 5 isolates and included subtypes from the IIc, IId and IIg families. This information contributes significantly to existing knowledge and understanding of C. parvum subtypes in Scotland which is vital in assisting with the management of future local and national outbreaks.
High densities of palms are common in many tropical forests. In some cases, the dominance of palms has been associated with a depauperate understorey and high rates of native seedling mortality. A variety of different potential mechanisms has been suggested to explain the sustained palm dominance in the understorey and canopy of these forests. Working in a Cocos nucifera-dominated wet tropical forest at Palmyra Atoll in the central Pacific, we examine how litterfall from this pantropical, and economically important palm, impacts seedling survival. We compare rates of litterfall, and rates of litterfall-associated damage, between forest stands dominated by C. nucifera (coconut palm) and forest stands with low abundance of C. nucifera. To assess litterfall damage we survey damage to both artificial seedlings (n = 711), outplanted real seedlings of two species (with and without protection via caging; n = 204), and standing rates of litterfall damage. We find that rates of large-litterfall damage were an average of five times higher in sites with high densities of C. nucifera. Associated with these increases we observe that levels of physical damage to artificial model seedlings caused by litterfall over a 4-mo period increased from 4.9% in sites with low abundance of C. nucifera to 16.1% in sites with high abundance of C. nucifera. Extrapolated to annual rates, litterfall damage of this magnitude exceeds the average levels observed in other published studies. Living native seedlings also showed more than 300% higher levels of mortality in forest stands with high densities of C. nucifera, a difference that was greatly reduced when protected by caging from litterfall. In contrast, uncaged C. nucifera seedlings actually had slightly higher survivorship in habitats dominated by conspecifics. We suggest that litterfall damage may be an important mechanism by which this tropical palm reaches and maintains near monodominance in many coastal and insular habitats.