To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Herbicide resistance is an increasing issue in many weed species, including rigid ryegrass (Lolium rigidum Gaudin); a major weed of winter cropping systems in southern Australia. Recently, this weed has also been found in summer crops in the southeastern region of Australia. Effective control of this herbicide-resistant weed across southeastern Australia requires alternative management strategies. These strategies can be informed by analyses on the interaction of germinable seeds with their regional environments and by identifying the differences between populations of varying herbicide-resistance levels. In this study, we explore how various environmental factors differentially affect the seed germination and seedling emergence of three L. rigidum populations, including one glyphosate-resistant population (GR), one glyphosate-susceptible population (GS), and one population of unknown resistance status (CC04). Germination was greater than 90% for all populations at each temperature regime, except 15/5 C. Populations germinated at a lower rate under 15/5 C, ranging from 74% to 87% germination. Salt stress had a similar effect on the germination of all populations, with 0% germination occurring at 250 mM salt stress. Population GS had greater tolerance to osmotic stress, with 65% germination at −0.4 MPa compared with 47% and 43% germination for CC04 and GR, respectively; however, germination was inhibited at −0.8 and −1.6 MPa for all populations. All populations had lower germination when placed in complete darkness as opposed to alternating light/dark. Germination in darkness was lower for CC04 (69%) than GR (83%) and GS (83%). Seedling emergence declined with increasing burial depth with the lowest emergence occuring at 8 cm (37%) when averaged over the populations. These results indicate that L. rigidum can survive under a range of environmental variables and that the extent of survival differs based on population; however, there was no difference based on herbicide-resistance status.
Targeted drug development efforts in patients with CHD are needed to standardise care, improve outcomes, and limit adverse events in the post-operative period. To identify major gaps in knowledge that can be addressed by drug development efforts and provide a rationale for current clinical practice, this review evaluates the evidence behind the most common medication classes used in the post-operative care of children with CHD undergoing cardiac surgery with cardiopulmonary bypass.
We systematically searched PubMed and EMBASE from 2000 to 2019 using a controlled vocabulary and keywords related to diuretics, vasoactives, sedatives, analgesics, pulmonary vasodilators, coagulation system medications, antiarrhythmics, steroids, and other endocrine drugs. We included studies of drugs given post-operatively to children with CHD undergoing repair or palliation with cardiopulmonary bypass.
We identified a total of 127 studies with 51,573 total children across medication classes. Most studies were retrospective cohorts at single centres. There is significant age- and disease-related variability in drug disposition, efficacy, and safety.
In this study, we discovered major gaps in knowledge for each medication class and identified areas for future research. Advances in data collection through electronic health records, novel trial methods, and collaboration can aid drug development efforts in standardising care, improving outcomes, and limiting adverse events in the post-operative period.
The peoples of southern Mesoamerica, including the Classic period Maya, are often claimed to exhibit a distinct type of spatial organization relative to contemporary urban systems. Here, we use the settlement scaling framework and properties of settlements recorded in systematic, full-coverage surveys to examine ways in which southern Mesoamerican settlement systems were both similar to and different from contemporary systems. We find that the population-area relationship in these settlements differs greatly from that reported for other agrarian settlement systems, but that more typical patterns emerge when one considers a site epicenter as the relevant social interaction area, and the population administered from a given center as the relevant interacting population. Our results imply that southern Mesoamerican populations mixed socially at a slower temporal rhythm than is typical of contemporary systems. Residential locations reflected the need to balance energetic and transport costs of farming with lower-frequency costs of commuting to central places. Nevertheless, increasing returns in activities such as civic construction were still realized through lower-frequency social mixing. These findings suggest that the primary difference between low-density urbanism and contemporary urban systems lies in the spatial and temporal rhythms of social mixing.
The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
Accurate low-dimensional models for the dynamics of falling liquid films subject to localized or time-varying heating are essential for applications that involve patterning or control. However, existing modelling methodologies either fail to respect fundamental thermodynamic properties or else do not accurately capture the effects of advection and diffusion on the temperature profile. We argue that the best-performing long-wave models are those that give the surface temperature implicitly as the solution of an evolution equation in which the wall temperature alone (and none of its derivatives) appears as a source term. We show that, for both flat and non-uniform films, such a model can be rationally derived by expanding the temperature field about its free-surface values. We test this model in linear and nonlinear regimes, and show that its predictions are in remarkable quantitative agreement with full Navier–Stokes calculations regarding the surface temperature, the internal temperature field and the surface displacement that would result from temperature-induced Marangoni stresses.
The rate of failing to apply a tourniquet remains high.
The study objective was to examine whether early advanced training under conditions that approximate combat conditions and provide stress inoculation improve competency, compared to the current educational program of non-medical personnel.
This was a randomized controlled trial. Male recruits of the armored corps were included in the study. During Combat Lifesaver training, recruits apply The Tourniquet 12 times. This educational program was used as the control group. The combat stress inoculation (CSI) group also included 12 tourniquet applications, albeit some of them in combat conditions such as low light and physical exertion. Three parameters defined success, and these parameters were measured by The Simulator: (1) applied pressure ≥ 200mmHg; (2) time to stop bleeding ≤ 60 seconds; and (3) placement up to 7.5cm above the amputation.
Out of the participants, 138 were assigned to the control group and 167 were assigned to the CSI group. The overall failure rate was 80.33% (81.90% in the control group versus 79.00% in the CSI group; P value = .565; 95% confidence interval, 0.677 to 2.122). Differences in pressure, time to stop bleeding, or placement were not significant (95% confidence intervals, −17.283 to 23.404, −1.792 to 6.105, and 0.932 to 2.387, respectively). Tourniquet placement was incorrect in most of the applications (62.30%).
This study found high rates of failure in tourniquet application immediately after successful completion of tourniquet training. These rates did not improve with tourniquet training, including CSI. The results may indicate that better tourniquet training methods should be pursued.
Tsur, AM, Binyamin, Y, Koren, L, Ohayon, S, Thompson; P, Glassberg, E. High tourniquet failure rates among non-medical personnel do not improve with tourniquet training, including combat stress inoculation: a randomized controlled trial. Prehosp Disaster Med. 2019;34(3):282–287.
Children with CHD and acquired heart disease have unique, high-risk physiology. They may have a higher risk of adverse tracheal-intubation-associated events, as compared with children with non-cardiac disease.
Materials and methods
We sought to evaluate the occurrence of adverse tracheal-intubation-associated events in children with cardiac disease compared to children with non-cardiac disease. A retrospective analysis of tracheal intubations from 38 international paediatric ICUs was performed using the National Emergency Airway Registry for Children (NEAR4KIDS) quality improvement registry. The primary outcome was the occurrence of any tracheal-intubation-associated event. Secondary outcomes included the occurrence of severe tracheal-intubation-associated events, multiple intubation attempts, and oxygen desaturation.
A total of 8851 intubations were reported between July, 2012 and March, 2016. Cardiac patients were younger, more likely to have haemodynamic instability, and less likely to have respiratory failure as an indication. The overall frequency of tracheal-intubation-associated events was not different (cardiac: 17% versus non-cardiac: 16%, p=0.13), nor was the rate of severe tracheal-intubation-associated events (cardiac: 7% versus non-cardiac: 6%, p=0.11). Tracheal-intubation-associated cardiac arrest occurred more often in cardiac patients (2.80 versus 1.28%; p<0.001), even after adjusting for patient and provider differences (adjusted odds ratio 1.79; p=0.03). Multiple intubation attempts occurred less often in cardiac patients (p=0.04), and oxygen desaturations occurred more often, even after excluding patients with cyanotic heart disease.
The overall incidence of adverse tracheal-intubation-associated events in cardiac patients was not different from that in non-cardiac patients. However, the presence of a cardiac diagnosis was associated with a higher occurrence of both tracheal-intubation-associated cardiac arrest and oxygen desaturation.
The suboptimal provision of analgesia to children in the emergency department (ED) is well-described. A yet unexplored barrier is caregiver or child refusal of analgesia. We sought to evaluate the frequency of caregiver/child acceptance of analgesia offered in the ED.
We conducted a two-centre cross-sectional study of 743 caregivers of children 4–17 years presenting to the pediatric ED with an acutely painful condition using a survey and medical record review. The primary outcome was the proportion of children/caregiver pairs who accepted analgesia in the ED.
The median (IQR) age of children was 11 (7) years, and 339/743 (45.6%) were female. The overall survey response rate was 73% (743/1018). In the 24 hours preceding ED arrival, the median (IQR) maximal pain score rated by children and caregivers was 8/10 (4) and 5/10 (2), respectively, and 30.4% (226/743) of caregivers offered analgesia. In the ED, children reported a median (IQR) pain score of 8/10 (2) and 54.9% (408/743) were offered analgesia. When offered in the ED, analgesia was accepted by 91% (373/408). Overall, 55.7% (414/743) of children received some form of analgesia.
Most caregivers/children accept analgesia when offered by ED personnel, suggesting refusal is not a major barrier to optimal management of children’s pain and highlighting the importance of ED personnel in encouraging adequate analgesia. A large proportion of children in pain are not offered analgesia by caregivers or ED personnel. Educational strategies for recognizing and treating pain should be directed at children, caregivers, and ED personnel.
One year of antipsychotic treatment from symptom remission is recommended following a first episode of psychosis (FEP).
To investigate the effectiveness of commonly used antipsychotic medications in FEP.
A retrospective cohort study of naturalistic treatment of patients (N = 460) accepted by FEP services across seven UK sites. Treatment initiation to all-cause discontinuation determined from case files.
Risk of treatment discontinuation is greatest within 3 months of treatment initiation. Risperidone had longest median survival time. No significant differences were observed in time to discontinuation between commonly used antipsychotics on multivariable Cox regression analysis. Poor adherence and efficacy failure were the most common reasons for discontinuation.
Effectiveness differences appear not to be a current reason for antipsychotic choice in FEP. Adherence strategies and weighing up likely adverse effects should be the clinical focus.
The Coronal Solar Magnetism Observatory (CoSMO) is a proposed new facility led by the High Altitude Observatory and a consortium of partners to measure magnetic field and plasma properties in a large (one degree) field of view extending down to the inner parts of the solar corona. CoSMO is intended as a research facility that will advance the understanding and prediction of space weather. The instrumentation elements of CoSMO are: a white-light coronagraph (KCor), already operational at the Mauna Loa Solar Observatory (MLSO); the Chromosphere and Prominence Magnetometer (ChroMag), due for deployment to MLSO next year; and the CoSMO Large Coronagraph (LC) which has completed Preliminary Design Review.
Malnutrition is common in children with CHD and is likely to place them at an increased risk for adverse surgical outcomes. We sought to evaluate the impact of preoperative malnutrition on outcomes after paediatric cardiac surgery.
We conducted a retrospective analysis of patients from age 0 to 5 years undergoing cardiac surgery at Seattle Children’s Hospital from 2006 to 2015. We used regression modelling to examine the impact of malnutrition on surgical outcomes.
We found a non-linear relationship between low height-for-age and weight-for-age z-scores and mortality after surgery. In the range of z-score ⩽−2, each additional unit decrease in height-for-age or weight-for-age z-score was associated with a 2.9 or 2.1% increased risk for mortality, respectively. Each unit decrease in height-for-age z-score was associated with a 1.2% increased risk for cardiac arrest, 1.1% increased risk for infection, and an average of 1.7 additional hours of mechanical ventilation, 6 hours longer ICU stay, and 13 hours longer hospital stay. Each unit decrease in weight-for-age z-score was associated with a 0.7% increased risk for cardiac arrest, 0.8% increased risk for infection, and an average of 1.9 additional hours of mechanical ventilation and 5.3 additional hours of ICU stay.
This study is unique in demonstrating a significant association between malnutrition and 30-day mortality and other adverse outcomes after paediatric cardiac surgery in a mixed population of CHD patients. By evaluating nutritional status as a continuous variable, we were able to clearly distinguish the point at which malnutrition begins to affect mortality.
Establishing a health screening protocol is fundamental for successful captive breeding and release of wildlife. The aim of this study was to undertake a parasitological survey focusing on the presence of trypanosomes in a cohort of Regent Honeyeaters, Anthochaera phrygia, syn. Xanthomyza phrygia (Aves: Passeriformes) that are part of the breeding and reintroduction programme carried out in Australia. We describe a new blood parasite, Trypanosoma thomasbancrofti sp. n. (Kinetoplastida: Trypanosomatidae) with prevalence of 24·4% (20/81) in a captive population in 2015. The sequence of the small subunit rRNA gene (SSU rDNA) and kinetoplast ultrastructure of T. thomasbancrofti sp. n. are the key differentiating characteristics from other Trypanosoma spp. T. thomasbancrofti sp. n. is distinct from Trypanosoma cf. avium found in sympatric Noisy Miners (Manorina melanocephala). The SSU rDNA comparison suggests an intercontinental distribution of T. thomasbancrofti sp. n. and Culex mosquitoes as a suspected vector. Currently, no information exists on the effect of T. thomasbancrofti sp. n. on its hosts; however, all trypanosome-positive birds remain clinically healthy. This information is useful in establishing baseline health data and screening protocols, particularly prior to release to the wild.
Evidence exists that analgesics are underutilized, delayed, and insufficiently dosed for emergency department (ED) patients with acute abdominal pain. For physicians practicing in a Canadian paediatric ED setting, we (1) explored theoretical practice variation in the provision of analgesia to children with acute abdominal pain; (2) identified reasons for withholding analgesia; and (3) evaluated the relationship between providing analgesia and surgical consultation.
Physician members of Paediatric Emergency Research Canada (PERC) were prospectively surveyed and presented with three scenarios of undifferentiated acute abdominal pain to assess management. A modified Dillman’s Tailored Design method was used to distribute the survey from June to July 2014.
Overall response rate was 74.5% (149/200); 51.7% of respondents were female and mean age was 44 (SD 8.4) years. The reported rates of providing analgesia for case scenarios representative of renal colic, appendicitis, and intussusception, were 100%, 92.1%, and 83.4%, respectively, while rates of providing intravenous opioids were 85.2%, 58.6%, and 12.4%, respectively. In all 60 responses where the respondent indicated they would obtain a surgical consultation, analgesia would be provided. In the 35 responses where analgesia would be withheld, 21 (60%) believed pain was not severe enough, while 5 (14.3%) indicated it would obscure a surgical condition.
Pediatric emergency physicians self-reported rates of providing analgesia for acute abdominal pain scenarios were higher than previously reported, and appeared unrelated to request for surgical consultation. However, an unwillingness to provide opioid analgesia, belief that analgesia can obscure a surgical condition, and failure to take self-reported pain at face value remain, suggesting that the need exists for further knowledge translation efforts.
Taming the beast of uncertainty has been the grand project to which actuaries have dedicated much of their energy and skill over at least the last 50 years – roughly the time since, in Hans Bühlmann's (1989) famous term, “Actuaries of the Second Kind” emerged.
Development of a photoelectrochemical conversion device, operated at room
temperature and ambient pressure with only ultraviolet radiation as an energy
source is presented. We report a nanocomposite platform that combines a
photocatalyst and an electrocatalyst capable of reducing gaseous Carbon Dioxide,
without using external electricity. The composite catalyst produces Methane from
Carbon Dioxide and atmospheric water vapor at an initial high conversion rate of
2596 μL of CH4 per gram of catalyst per hour, which is
amongst the highest reported. Our new approach offers a versatile solution to
reduce the rising level of atmospheric Carbon Dioxide where a source of light is
Prominent moraines deposited by the Laurentide Ice Sheet in northern New England document readvances, or stillstands, of the ice margin during overall deglaciation. However, until now, the paucity of direct chronologies over much of the region has precluded meaningful assessment of the mechanisms that drove these events, or of the complex relationships between ice-sheet dynamics and climate. As a step towards addressing this problem, we present a cosmogenic 10Be surface-exposure chronology from the Androscoggin moraine complex, located in the White Mountains of western Maine and northern New Hampshire, as well as four recalculated ages from the nearby Littleton–Bethlehem moraine. Seven internally consistent 10Be ages from the Androscoggin terminal moraines indicate that advance culminated ~ 13.2 ± 0.8 ka, in close agreement with the mean age of the neighboring Littleton–Bethlehem complex. Together, these two datasets indicate stabilization or advance of the ice-sheet margin in northern New England, at ~ 14–13 ka, during the Allerød/Greenland Interstadial I.