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Introduction: We previously derived (N = 559) and validated (N = 1,100) the 10-item Ottawa Heart Failure Risk Scale (OHFRS), to assist with disposition decisions for patients with acute heart failure (AHF) in the emergency department (ED). In the current study we sought to use a larger dataset to develop a more concise and more accurate risk scale. Methods: We analyzed data from the prior two studies and from a new cohort. For all 3 groups we conducted prospective cohort studies that enrolled patients who required treatment for AHF at 8 tertiary care hospital EDs. Patients were followed for 30 days. The primary outcome was short-term serious outcome (SSO), defined as death within 30 days, intubation or non-invasive ventilation (NIV) after admission, myocardial infarction, or relapse resulting in hospital admission within 14 days. The fully pre-specified logistic regression model with 13 predictors (where age, pCO2, and SaO2 were modeled using spline functions) was fitted to 10 multiple imputation datasets. Harrell's fast stepdown procedure reduced the number of variables. We calculated the potential impact on sensitivity (95% CI) for SSO and hospital admissions, and estimated a sample size of 2,000 patients. Results: The 1,986 patients had mean age 77.3 years, male 54.1%, EMS arrival 41.2%, IV NTG 3.3%, ED NIV 5.4%, admission on initial visit 49.5%. Overall there were 236 (11.9%) SSOs including 61 deaths (3.1%), meaning that current admission practice sensitivity for SSO was only 59.7%. The final HEARTRISK6 scale is comprised of 6 variables (points) (C-statistic 0.68): Valvular heart disease (2) Antiarrhythmic medication (2) ED non-invasive ventilation (3) Creatinine 80–150 (1); ≥150 (3) Troponin ≥3x URL (2) Walk test failed (1). The probability of SSO ranged from 4.8% for a total score of 0 to 62.4% for a score of 10, showing good calibration. Choosing a HEARTRISK6 total point admission threshold of ≥3 would yield sensitivity of 70.8% (95%CI 64.5-76.5) for SSO with a slight decrease in admissions to 47.9%. Choosing a threshold of ≥2 would yield a sensitivity of 84.3% (95%CI 79.0-88.7) but require 66.6% admissions. Conclusion: Using a large prospectively collected dataset, we created a more concise and more sensitive risk scale to assist with admission decisions for patients with AHF in the ED. Implementation of the HEARTRISK6 scale should lead to safer and more efficient disposition decisions, with more high-risk patients being admitted and more low-risk patients being discharged.
After five positive randomized controlled trials showed benefit of mechanical thrombectomy in the management of acute ischemic stroke with emergent large-vessel occlusion, a multi-society meeting was organized during the 17th Congress of the World Federation of Interventional and Therapeutic Neuroradiology in October 2017 in Budapest, Hungary. This multi-society meeting was dedicated to establish standards of practice in acute ischemic stroke intervention aiming for a consensus on the minimum requirements for centers providing such treatment. In an ideal situation, all patients would be treated at a center offering a full spectrum of neuroendovascular care (a level 1 center). However, for geographical reasons, some patients are unable to reach such a center in a reasonable period of time. With this in mind, the group paid special attention to define recommendations on the prerequisites of organizing stroke centers providing medical thrombectomy for acute ischemic stroke, but not for other neurovascular diseases (level 2 centers). Finally, some centers will have a stroke unit and offer intravenous thrombolysis, but not any endovascular stroke therapy (level 3 centers). Together, these level 1, 2, and 3 centers form a complete stroke system of care. The multi-society group provides recommendations and a framework for the development of medical thrombectomy services worldwide.
The current experiment aimed at assessing the effects of dietary supplementation of guanidino acetic acid (GAA) on growth performance, thigh meat quality and development of small intestine in broilers. A total of 360 1-day-old female broiler chicks were distributed randomly to four groups of 90 birds each, and each group received GAA dosages of 0, 0.4, 0.8 and 1.2 g/kg of feed dry matter. During the whole experiment of 60 days, broilers had ad libitum access to water and feed and the feed intake was recorded daily. All broilers were weighed before and after the experiment, and 30 broilers of each group were selected randomly to slaughter at the end. Increasing dietary supplementation of GAA increased final live weight and daily body weight gain, gain-to-feed ratio, thigh muscle pH value and fibre diameter of broilers, but decreased daily feed intake, drip loss, cooking loss, shear force value, hardness, gumminess and chewiness of thigh meat. In addition, increasing supplementation of GAA quadratically increased duodenal, jejunal and ileal villus height and width and ratio of villus height to crypt depth, but decreased crypt depth. The results indicated that GAA as a feed additive may support better development of small intestine, thereby resulting in improvement of growth performance and meat quality of broilers.
Monolithic integrated thin film tandem solar cells consisting of a high bandgap perovskite top cell and a low bandgap thin film bottom cell are expected to reach higher power conversion efficiencies (PCEs) with lower manufacturing cost and environmental impacts than the market-dominant crystalline silicon photovoltaics. There have been several demonstrations of 4-terminal and 2-terminal perovskite tandem devices with CuInGaSe2 (CIGS) or CuInSe2 (CIS) and, similar to the other tandem structures, the optimization of this device relies on optimal choice for the perovskite bandgap and thickness. Therefore, further advancement will be enabled by tuning the perovskite absorber to maximize the photocurrent limited by the current match condition. Here, we systematically study the optical absorption and transmission of perovskite thin films with varying absorber band gap. Based on these results, we model the photocurrent generations in both perovskite and CIS subcells and estimate the performances of projected tandem devices by considering the ideally functioning perovskite and CIS device. Our results show that for perovskite layers with 500 nm thickness the optimal bandgap is around 1.6 eV. With these configurations, PCEs above 20% could be achieved by monolithically integrated perovskite/CIS tandem solar cells. Also by modelling the absorption at every layer we calculate the quantum efficiency at each subcell in addition to tracking optical losses.
Methods of obtaining large grain size and high crystallinity in absorber materials play an important role in fabrication of high-performance methylammonium lead iodide (MAPbI3) perovskite solar cells. Here we study the effect of adding small concentrations of Cd2+, Zn2+, and Fe2+salts to the perovskite precursor solution used in the single-step solution fabrication process. Enhanced grain size and crystallinity in MAPbI3 films were obtained by using 0.1% of Cd2+ or Zn2+in the precursor solution. Consequently, solar cells constructed with Cd- and Zn-doped perovskite films show a significant improvement in device performance. These results suggest that the process may be an effective and facile method to fabricate high-efficiency perovskite photovoltaic devices.
Curcumin has been attributed with antioxidant, anti-inflammatory, antibacterial activities, and has shown highly protective effects against enteropathogenic bacteria and mycotoxins. Ochratoxin A (OTA) is one of the major intestinal pathogenic mycotoxins. The possible effect of curcumin on the alleviation of enterotoxicity induced by OTA is unknown. The effects of dietary curcumin supplementation on OTA-induced oxidative stress, intestinal barrier and mitochondrial dysfunctions were examined in young ducks. A total of 540 mixed-sex 1-day-old White Pekin ducklings with initial BW (43.4±0.1 g) were randomly assigned into controls (fed only the basal diet), a group fed an OTA-contaminated diet (2 mg/kg feed), and a group fed the same OTA-contaminated feed plus 400 mg/kg of curcumin. Each treatment consisted of six replicates, each containing 30 ducklings and treatment lasted for 21 days. There was a significant decrease in average daily gain (ADG) and increased feed : gain caused by OTA (P<0.05); curcumin co-treatment prevented the decrease in BW and ADG compared with the OTA group (P<0.05). Histopathological and ultrastructural examination showed clear signs of enterotoxicity caused by OTA, but these changes were largely prevented by curcumin supplementation. Curcumin decreased the concentrations of interleukin-1β, tumor necrosis factor-α and malondialdehyde, and increased the activity of glutathione peroxidase induced by OTA in the jejunal mucosa of ducks (P<0.05). Additionally, curcumin increased jejunal mucosa occludin and tight junction protein 1 mRNA and protein levels, and decreased those of ρ-associated protein kinase 1 (P<0.05). Notably, curcumin inhibited the increased expression of apoptosis-related genes, and downregulated mitochondrial transcription factors A, B1 and B2 caused by OTA without any effects on RNA polymerase mitochondrial (P<0.05). These results indicated that curcumin could protect ducks from OTA-induced impairment of intestinal barrier function and mitochondrial integrity.
The triplite LiFeSO4F displays both the highest potential ever reported for an Fe-based compound, as well as a comparable specific energy with that of popular LiFePO4. The synthesis is still a challenge because the present approaches are connected with long time, special equipments or organic reagents, etc. In this work, the triplite LiFeSO4F powder was synthesized through an ambient two-step solid-state route. The reaction process and phase purity were analyzed, coupled with structure refinement and electrochemical test.
There is little information available in the literature on the validation of the currently adopted energy feeding systems developed from calorimetric data, using data obtained in production studies. The objective of the present study was to use production data from feeding studies to validate some metabolisable energy (ME) systems (AFRC, 1990 and 1993; SCA, 1990) and net energy (NE) systems (Van Es, 1978, INRA, 1989; NRC, 2001).
Holstein-Friesian cattle are the predominant breed of dairy cattle in Northern Ireland. Breeding programmes for the Holstein Friesian have focused on improved milk production with little emphasis on functional traits such as fertility or disease resistance. In contrast Norwegian dairy cattle have been bred via a multi-trait selection procedure and there is evidence that problems associated with disease and fertility have tended to decrease in recent years. It is important, however, to investigate possible differences in efficiency of food use and partitioning of nutrients between the two breeds which may offset the potential advantages of improvements in secondary characteristics. Consequently, the objectives of this experiment were firstly to investigate the effects of breed type on the efficiency of utilization and partitioning of nutrients for milk production and secondly to investigate if there are differences in the energy requirement for maintenance and the efficiency of utilization of ME for lactation (kl) between the two breeds.
AFRC (1993) recommends a reduction of proportionately 0.018 in dietary metabolisble energy (ME) concentration with each unit increase in feeding level above maintenance in dairy cows (feeding level is calculated as total ME intake divided by ME requirement for maintenance). A similar value (0.016) was reported recently by Yan et al. (2001) using a number of linear and multiple regression techniques with lactating dairy cows offered grass silage-based diets. The objectives of the present study were to validate these two values and also to evaluate the effects of feeding level on nutrient digestibility and ME concentration in the mixed diets.
The energy feeding systems currently adopted for dairy cows in Western Europe and North America were developed from calorimetric data published 30 years ago. However, the calorimetric measurements were usually undertaken with a small number of trained animals, housed for a short period in respiration chambers. The objective of the present study was to use production data to develop the metabolisable energy (ME) requirement for maintenance (MEm) and the efficiency of ME use for lactation (kl) for dairy cows.
San Pietro and Rittenberg (1953) reported that urea appeared to meet all the requirements of a satisfactory tracer. Urea is non toxic, not foreign to the body and it shows an even and rapid distribution throughout the total body water without any physiological effect. For these reasons in addition to its easy and accurate measurement, urea is an ideal candidate tracer to estimate empty body water in vivo. Total body water volume (urea space) can be estimated by dividing the total amount of urea infused by the increase in plasma urea concentration from prior to infusion until 12 or 30 minutes after mean infusion time. Kock and Preston (1973) reported significant relationships between urea space measurements and percentage of empty body fat and water in cattle. However, Andrew et al. (1995) using 21 Holstein cows showed that prediction of empty body water using the urea space technique only explained 31 % of the variation. The objective of this experiment was to use the urea dilution technique to estimate the body composition of lactating dairy cows and produce relationships between urea space and body fat and protein content.
In an extensive review of energy metabolism of dairy cows, Agnew and Yan (2000) concluded that high genetic merit cows are capable of partitioning more energy into milk and less into body tissue when compared to low genetic merit cows. The objective of the present study was to use production data for a complete lactation to evaluate the effect of cow genotype on energy partitioning between milk and body tissue.
Wilting of grass prior to ensiling generally produces positive responses in dry matter (DM) intake of cattle, but the responses in animal performance are often small, or even negative. The primary objective of the present study was to compare energy utilization from heavily wilted and unwilted silages by growing cattle when given at equal metabolisable energy (ME) intakes. A secondary objective was to evaluate effects of silage additive type (inoculant v. formic acid) on energy utilization.
Four silages were produced from unwilted and wilted grasses (DM 193 and 450 g/kg) obtained from a perennial ryegrass sward. The wilted grass was dried in the field for 26 hours using rapid wilting techniques involving crop conditioning and spreading. At ensiling both the unwilted and wilted grasses were each treated with two additives, a bacterial inoculant (Ecosyl, Zeneca Bioproducts Limited) and a formic acid additive (ADD-F, BP Chemicals Ltd.).
This paper presents the bed topography of Jakobshavn Isbræ, Greenland, and Byrd Glacier, Antarctica, derived from sounding these glaciers with high-sensitivity radars. To understand the processes causing the speed-up and retreat of outlet glaciers, and to enable the development of next-generation ice-sheet models, we need information on bed topography and basal conditions. To this end, we performed measurements with the progressively improved Multichannel Coherent Radar Depth Sounder/Imager (MCoRDS/I). We processed the data from each antenna-array element using synthetic aperture radar algorithms to improve radar sensitivity and reduce along-track surface clutter. We then applied array and image-processing algorithms to extract the weak bed echoes buried in off-vertical scatter (cross-track surface clutter). At Jakobshavn Isbræ, we observed 2.7 km thick ice ~30 km upstream of the calving front and ~850 m thick ice at the calving front. We also observed echoes from multiple interfaces near the bed. We applied the MUSIC algorithm to the data to derive the direction of arrival of the signals. This analysis revealed that clutter is dominated by the ice surface at Jakobshavn Isbræ. At Byrd Glacier, we found ~3.62 km thick ice, as well as a subglacial trench ~3.05 km below sea level. We used ice thickness information derived from radar data in conjunction with surface elevation data to generate bed maps for these two critical glaciers. The performance of current radars must be improved further by ~15 dB to fully sound the deepest part of Byrd Glacier. Unmanned aerial systems equipped with radars that can be flown over lines spaced as close as 5 m apart in the cross-track direction to synthesize a two-dimensional aperture would be ideal for collecting fine-resolution data over glaciers like Jakobshavn near their grounding lines.
One view of major Solar Energetic Particle (SEP) events is that these (proton-dominated) fluxes are accelerated in heliospheric shock sources created by Interplanetary Coronal Mass Ejections (ICMEs), and then travel mainly along interplanetary magnetic field lines connecting the shock(s) to the observer(s). This places a particular emphasis on the role of the heliospheric conditions during the event, requiring a realistic description of the latter to interpret and/or model SEP events. The well-known ENLIL heliospheric simulation with cone model generated ICME shocks is used together with the SEPMOD particle event modeling scheme to demonstrate the value of applying these concepts at multiple inner heliosphere sites.
A Lean Premixed Prevaporised (LPP) low-emission combustor with a staged lean combustion technology was developed. In order to study cold-flow dynamics in the LPP combustor, both experimental tests using the particle image velocimetry (PIV) to quantify the flow dynamics and numerical simulation using the commercial software (FLUENT) were conducted, respectively. Numerical results were in good agreement with the experimental data. It is shown from the observation of the results that: there is a Primary Recirculation Zone (PRZ), a Corner Recirculation Zone (CRZ) and a Lip Recirculation Zone (LRZ) in the LPP combustor, and the exchanges of mass, momentum and energy between pilot swirling flow and primary swirling flow are contributed by the velocity gradients, and the shear flow is transformed into a mixing layer exhibiting the higher Reynolds stresses, which suggests the mixing process is strictly affected by the Reynolds stresses.
Studies of schizophrenia at drug-naive state and on antipsychotic medication have reported a number of regions of gray-matter (GM) abnormalities but the reports have been inconsistent. The aim of this study was to conduct multimodal meta-analysis to compare the cross-sectional voxel-based morphometry studies of brain GM in antipsychotic-naive first-episode schizophrenia (AN-FES) and those with antipsychotic treatment within 1 year (AT-FES) to determine the similarities and differences in these groups. We conducted two separate meta-analyses containing 24 studies with a sample size of 801 patients and 957 healthy controls. A multimodal meta-analysis method was used to compare the findings between AN-FES and AT-FES. Meta-regression analyses were done to determine the influence of different variables including age, duration of illness, and positive and negative symptom scores. Finally, jack-knife analyses were done to test the robustness of the results. AN-FES and AT-FES showed common patterns of GM abnormalities in frontal (gyrus rectus), superior temporal, left hippocampal and insular cortex. GM in the left supramarginal gyrus and left middle temporal gyrus were found to be increased in AN-FES but decreased in AT-FES, whereas left median cingulate/paracingulate gyri and right hippocampus GM was decreased in AN-FES but increased in AT-FES. Findings suggest that both AN-FES and AT-FES share frontal, temporal and insular regions as common anatomical regions to be affected indicating these to be the primary regions of GM abnormalities in both groups.