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Over the last 25 years, radiowave detection of neutrino-generated signals, using cold polar ice as the neutrino target, has emerged as perhaps the most promising technique for detection of extragalactic ultra-high energy neutrinos (corresponding to neutrino energies in excess of 0.01 Joules, or 1017 electron volts). During the summer of 2021 and in tandem with the initial deployment of the Radio Neutrino Observatory in Greenland (RNO-G), we conducted radioglaciological measurements at Summit Station, Greenland to refine our understanding of the ice target. We report the result of one such measurement, the radio-frequency electric field attenuation length $L_\alpha$. We find an approximately linear dependence of $L_\alpha$ on frequency with the best fit of the average field attenuation for the upper 1500 m of ice: $\langle L_\alpha \rangle = ( ( 1154 \pm 121) - ( 0.81 \pm 0.14) \, ( \nu /{\rm MHz}) ) \,{\rm m}$ for frequencies ν ∈ [145 − 350] MHz.
To develop a physiological data-driven model for early identification of impending cardiac arrest in neonates and infants with cardiac disease hospitalised in the cardiovascular ICU.
Methods:
We performed a single-institution retrospective cohort study (11 January 2013–16 September 2015) of patients ≤1 year old with cardiac disease who were hospitalised in the cardiovascular ICU at a tertiary care children’s hospital. Demographics and diagnostic codes of cardiac arrest were obtained via the electronic health record. Diagnosis of cardiac arrest was validated by expert clinician review. Minute-to-minute physiological monitoring data were recorded via bedside monitors. A generalized linear model was used to compute a minute by minute risk score. Training and test data sets both included data from patients who did and did not develop cardiac arrest. An optimal risk-score threshold was derived based on the model’s discriminatory capacity for impending arrest versus non-arrest. Model performance measures included sensitivity, specificity, accuracy, likelihood ratios, and post-test probability of arrest.
Results:
The final model consisting of multiple clinical parameters was able to identify impending cardiac arrest at least 2 hours prior to the event with an overall accuracy of 75% (sensitivity = 61%, specificity = 80%) and observed an increase in probability of detection of cardiac arrest from a pre-test probability of 9.6% to a post-test probability of 21.2%.
Conclusions:
Our findings demonstrate that a predictive model using physiologic monitoring data in neonates and infants with cardiac disease hospitalised in the paediatric cardiovascular ICU can identify impending cardiac arrest on average 17 hours prior to arrest.
We reviewed all patients who were supported with extracorporeal membrane oxygenation and/or ventricular assist device at our institution in order to describe diagnostic characteristics and assess mortality.
Methods
A retrospective cohort study was performed including all patients supported with extracorporeal membrane oxygenation and/or ventricular assist device from our first case (8 October, 1998) through 25 July, 2016. The primary outcome of interest was mortality, which was modelled by the Kaplan–Meier method.
Results
A total of 223 patients underwent 241 extracorporeal membrane oxygenation runs. Median support time was 4.0 days, ranging from 0.04 to 55.8 days, with a mean of 6.4±7.0 days. Mean (±SD) age at initiation was 727.4 days (±146.9 days). Indications for extracorporeal membrane oxygenation were stratified by primary indication: cardiac extracorporeal membrane oxygenation (n=175; 72.6%) or respiratory extracorporeal membrane oxygenation (n=66; 27.4%). The most frequent diagnosis for cardiac extracorporeal membrane oxygenation patients was hypoplastic left heart syndrome or hypoplastic left heart syndrome-related malformation (n=55 patients with HLHS who underwent 64 extracorporeal membrane oxygenation runs). For respiratory extracorporeal membrane oxygenation, the most frequent diagnosis was congenital diaphragmatic hernia (n=22). A total of 24 patients underwent 26 ventricular assist device runs. Median support time was 7 days, ranging from 0 to 75 days, with a mean of 15.3±18.8 days. Mean age at initiation of ventricular assist device was 2530.8±660.2 days (6.93±1.81 years). Cardiomyopathy/myocarditis was the most frequent indication for ventricular assist device placement (n=14; 53.8%). Survival to discharge was 42.2% for extracorporeal membrane oxygenation patients and 54.2% for ventricular assist device patients. Kaplan–Meier 1-year survival was as follows: all patients, 41.0%; extracorporeal membrane oxygenation patients, 41.0%; and ventricular assist device patients, 43.2%. Kaplan–Meier 5-year survival was as follows: all patients, 39.7%; extracorporeal membrane oxygenation patients, 39.7%; and ventricular assist device patients, 43.2%.
Conclusions
This single-institutional 18-year review documents the differential probability of survival for various sub-groups of patients who require support with extracorporeal membrane oxygenation or ventricular assist device. The indication for mechanical circulatory support, underlying diagnosis, age, and setting in which cannulation occurs may affect survival after extracorporeal membrane oxygenation and ventricular assist device. The Kaplan–Meier analyses in this study demonstrate that patients who survive to hospital discharge have an excellent chance of longer-term survival.
The effect of annual defoliation on leafy spurge-infested rangeland was investigated over a 5-yr period. Artificial defoliation was conducted once or twice annually at various phenological growth stages of leafy spurge to simulate grazing by herded Angora goats. Single defoliation treatments did not reduce total leafy spurge stem densities. Defoliation twice in a growing season for 4 consecutive yr reduced total leafy spurge stem densities by 55% over nondefoliated controls. Grass foliar cover and yield increased in all defoliation treatments. Despite the increased grass yield on single defoliation treatments, cattle use would likely be limited in these treatments due to the high density of leafy spurge stems. Stem densities of leafy spurge in twice-defoliated treatments should not deter cattle from grazing these sites, thereby increasing the available forage supply. The data suggest that repeated grazing of leafy spurge-infested rangeland within a growing season would be required to reduce stem densities adequately and increase cattle use and production from these sites.
Angora goats have been suggested as biological control agents for leafy spurge, especially in environmentally sensitive or limited access areas. Dietary preferences and dietary nutritive content of herded Angora goats were evaluated over a two-year period in North Dakota. Relative preferences of forages were evaluated by comparing botanical composition of diets as determined by microhistological analysis of fecal samples to forage availability in the field. Leafy spurge and shrubs comprised the largest percentage of goat diets throughout each grazing season. Goats preferred leafy spurge and shrubs at all times and avoided most cool-season grass species. The nutritional requirements of Angora goats nursing kids were met throughout the grazing season. Use of Angora goats is another tool available to land managers to manage leafy spurge infestations in the Northern Plains.
Adverse psychosocial working environments characterized by job strain (the combination of high demands and low control at work) are associated with an increased risk of depressive symptoms among employees, but evidence on clinically diagnosed depression is scarce. We examined job strain as a risk factor for clinical depression.
Method
We identified published cohort studies from a systematic literature search in PubMed and PsycNET and obtained 14 cohort studies with unpublished individual-level data from the Individual-Participant-Data Meta-analysis in Working Populations (IPD-Work) Consortium. Summary estimates of the association were obtained using random-effects models. Individual-level data analyses were based on a pre-published study protocol.
Results
We included six published studies with a total of 27 461 individuals and 914 incident cases of clinical depression. From unpublished datasets we included 120 221 individuals and 982 first episodes of hospital-treated clinical depression. Job strain was associated with an increased risk of clinical depression in both published [relative risk (RR) = 1.77, 95% confidence interval (CI) 1.47–2.13] and unpublished datasets (RR = 1.27, 95% CI 1.04–1.55). Further individual participant analyses showed a similar association across sociodemographic subgroups and after excluding individuals with baseline somatic disease. The association was unchanged when excluding individuals with baseline depressive symptoms (RR = 1.25, 95% CI 0.94–1.65), but attenuated on adjustment for a continuous depressive symptoms score (RR = 1.03, 95% CI 0.81–1.32).
Conclusions
Job strain may precipitate clinical depression among employees. Future intervention studies should test whether job strain is a modifiable risk factor for depression.
Bitter gourd (Momordica charantia L.) is an important market vegetable in the tropics. The objectives of this study were to (1) conduct a preliminary evaluation of genetic diversity in bitter gourd flesh (without seeds) for phytonutrient (carotenoid, ascorbic acid and tocopherol) contents with the aim to understand which phytonutrients might be increased through breeding, (2) assess the association between fruit traits and phytonutrient contents and (3) evaluate the effect of the fruit harvest stage on phytonutrient contents. A total of 17 diverse bitter gourd entries of various commercial market types were evaluated for fruit traits and phytonutrient contents for 2 years. Significant differences (P= 0.05) among the entries were detected for total carotenoids, total tocopherols, dry matter and fruit traits. Mean total carotenoid contents of the entries ranged from 10 to 1335 μg/100 g fresh weight in year 1 and 10 to 1185 μg/100 g fresh weight in year 2. Mean ascorbic acid contents were 69 and 61 mg/100 g fresh weight in year 1 and year 2, respectively. Total tocopherol contents among the entries ranged from 480 to 1345 and 445 to 2145 μg/100 g fresh weight in year 1 and year 2, respectively. Total carotenoid and ascorbic acid contents were highest at 12 days after fruit set (DAFS), but total tocopherol contents were highest from 14 to 20 DAFS. A 100 g portion of bitter gourd fruit can meet 190, 17 and 8% of the recommended daily allowances of vitamin C, vitamin E and vitamin A, respectively, for adults.
Both maternal 25-hydroxyvitamin D (25(OH)D) concentrations during pregnancy andplacental amino acid transporter gene expression have been associated withdevelopment of the offspring in terms of body composition and bone structure.Several amino acid transporter genes have vitamin D response elements in theirpromoters suggesting the possible linkage of these two mechanisms. We aimed toestablish whether maternal 25(OH)D and vitamin D-binding protein (VDBP) levelsrelate to expression of placental amino acid transporters. RNA was extractedfrom 102 placental samples collected in the Southampton Women's Survey,and gene expression was analysed using quantitative real-time PCR. Geneexpression data were normalised to the geometric mean of three housekeepinggenes, and related to maternal factors and childhood body composition. Maternalserum 25(OH)D and VDBP levels were measured by radioimmunoassay. Maternal25(OH)D and VDBP levels were positively associated with placental expression ofspecific genes involved in amino acid transport. Maternal 25(OH)D and VDBPconcentrations were correlated with the expression of specific placental aminoacid transporters, and thus may be involved in the regulation of amino acidtransfer to the fetus. The positive correlation of VDBP levels and placentaltransporter expression suggests that delivery of vitamin D to the placenta maybe important. This exploratory study identifies placental amino acidtransporters which may be altered in response to modifiable maternal factors andprovides a basis for further studies.
Poor nutrition during fetal development can permanently alter growth, cardiovascular physiology and metabolic function. Animal studies have shown that prenatal undernutrition followed by balanced postnatal nutrition alters deoxyribonucleic acid (DNA) methylation of gene promoter regions of candidate metabolic control genes in the liver. The aim of this study was to investigate whether methylation status of the proximal promoter regions of four candidate genes differed between individuals exposed to the Dutch famine in utero. In addition, we determined whether methylation status of these genes was associated with markers of metabolic and cardiovascular disease and adult lifestyle. Methylation status of the GR1-C (glucocorticoid receptor), PPARγ (peroxisome proliferator-activated receptor gamma), lipoprotein lipase and phosphatidylinositol 3 kinase p85 proximal promoters was investigated in DNA isolated from peripheral blood samples of 759 58-year-old subjects born around the time of the 1944–45 Dutch famine. We observed no differences in methylation levels of the promoters between exposed and unexposed men and women. Methylation status of PPARγ was associated with levels of high-density lipoprotein cholesterol and triglycerides as well as with exercise and smoking. Hypomethylation of the GR promoter was associated with adverse adult lifestyle factors, including higher body mass index, less exercise and more smoking. The previously reported increased risk of cardiovascular and metabolic disease after prenatal famine exposure was not associated with differences in methylation status across the promoter regions of these candidate genes measured in peripheral blood. The adult environment seems to affect GR and PPARγ promoter methylation.
Environmental exposures throughout the life course, including nutrition, may induce phenotypic and epigenetic changes. There is limited information about how timing affects the nature of such effects induced by a specific nutritional exposure. We investigated the effect of increased exposure to folic acid before birth or during the juvenile–pubertal period in rats on the epigenetic regulation of glucose homeostasis. Rats were fed either a folic acid-adequate (AF; 1 mg/kg feed) or a folic acid-supplemented (FS; 5 mg/kg feed) diet from conception until delivery and then an AF diet during lactation. Juvenile rats were fed either the AF or the FS diet from weaning for 28 d and then an AF diet. Liver and blood were collected after a 12 h fast between postnatal days 84 and 90. Maternal FS diet increased plasma glucose concentration significantly (P < 0·05) in females, but not in males. Post-weaning FS diet decreased glucose concentration significantly in females, but increased glucose concentration in males. There were no effects of the FS diet on phosphoenolpyruvate carboxykinase (PEPCK) mRNA expression in males, while the pattern of expression was related to plasma glucose concentration in females. The FS diet induced specific changes in the methylation of individual CpG in females, but not in males, which were related to the time of exposure. Methylation of CpG − 248 increased the binding of CCAAT-enhancer-binding protein β to the PEPCK promoter. Together, these findings show that both the period during the life course and sex influence the effect of increased exposure to folic acid on the epigenetic regulation of PEPCK and glucose homeostasis.
Three experiments were carried out to measure grain and biomass yields of spring barley breeding lines and varieties. Leaf diseases were controlled by applying proprietary fungicides and in some treatments plants were supported by nets to prevent lodging. The trials, grown in 1982 and 1983, compared the grain and biomass yields of 14 breeding lines and two varieties with and without support. In a third experiment, comparing three lines and the varieties Triumph and Egmont, all the plots were supported and in addition each experimental plot was flanked by guard plots of the same genotype to minimize inter-plot competition.
In the supported plots of all three experiments, three breeding lines, SB 543–3, SB 71–2 and HSB 258–93 produced significantly greater biomass yields than the mean of the varieties Triumph and Egmont. All three breeding lines were taller and had lower ratios of grain to grain + straw than the controls. Measurements were made of the accumulation of dry matter, chlorophyll content at anthesis and date of ear emergence but no single factor could be identified which was associated with increased biomass in these lines.
The grain yield of the semi-dwarf, lodging-resistant variety Triumph was reduced by an average of 0·24 t/ha by the support treatment compared with the non-supported control. The results from the third experiment suggested that the yield of Triumph was reduced by inter-plot competition by about 10% in relation to the other entries in the trial.
It is suggested that the high biomass lines identified here could be used as parents in a breeding programme to produce varieties with high yield if this high biomass could be combined with a high ratio of grain to above-ground dry-matter yield.
Leaf proportions (LP) were determined in spring barley straws harvested at Cambridge in 1984 and 1985. Linear regression equations showed that a greater number of days to flowering increased LP whilst greater plant height decreased LP in spring barley straws. Plant height accounted for more than 70% of the variance in LP. By contrast, grain yield and stem diameter accounted for only a small percentage of the variance in LP. Straws from two-rowed winter barleys had slightly higher LP than six-rowed winter barleys but LP in winter and spring barleys were similar.
Leaf blade and leaf sheath fractions of the straws had lower acid detergent fibre and lignin contents and were more digestible than the stem fractions. Linear regression equations of straw digestibility in spring barleys on LP, grain yields, days to flowering and plant heights showed that LP accounted for a higher percentage of the variance in digestibility in 1984 than the other characteristics. In 1985, when harvesting conditions were unusually wet, grain yield accounted for the highest percentage of the variance in straw digestibility.
There were no differences in chemical composition and straw digestibility between two-rowed and six-rowed barleys, but winter barleys had higher straw digestibility than spring barleys. Date of sowing did not influence straw quality in two-rowed winter barleys.
The ranking of two-rowed spring barleys for LP, chemical composition and digestibility suggested that varieties with consistently better straw quality could be identified.
Eight varieties of spring barley differing in their morphology and resistance to lodging were grown in a trial as main plots which were split for seven treatments: a natural control (C), a control with plots which were mechanically supported (S) and four artificially induced lodging treatments: permanent early lodging (PEL); temporary early lodging (TEL); permanent late lodging (PLL) and temporary late lodging (TLL). The seventh treatment (GR) was an application of the growth regulator BAS 09800W. In comparison with S, treatments PEL, TEL, PLL and TLL reduced grain yield by 38–1, 24–8, 22–0 and 13–9 % respectively. Natural lodging in C plots reduced the yield of the two weakest strawed varieties, Guilden and Jupiter, by 8 and 10% respectively in comparison with treatment S. Yields (C) of these two varieties were increased by GR which had no effect on the yield of other varieties, but reduced grain size in some cases. Treatment GR significantly reduced but did not eliminate natural lodging in weaker strawed varieties and reduced the length of the top four internodes. Lodging reduced grain size in terms of 1000–grain weight and sieving fractions and increased the content of husk and protein. Lodging susceptibility was positively correlated with plant height but showed no clear relationship with the number of vascular bundles, stem diameter, wall thickness, or with the content of lignin, cellulose and hemicellulose in the basal internodes. Lodging resistance appeared to be closely associated with short basal internodes.
Five experiments, involving 37 varieties, were carried out over three seasons to estimate the increase in yield potential in spring barley achieved by plant breeding during the last 100 years. Most of the important spring barley varieties grown in Britain between 1880 and 1980 were represented. In three experiments disease was controlled by a fungicide while in the other two experiments fungicide application was a main treatment. To prevent yield loss due to lodging, plants were supported as a main treatment in two trials.
In all experiments most of the modern varieties yielded more than the older ones. The genetic gain in yield was 0·39% per year during the 100-year period and 0·84% per year between 1953 and 1980.
Modern varieties had higher grain yields, shorter straw, and higher harvest index denned as the proportion of grain dry weight to total above-ground dry weight; more of the tillers they produced survived to give ears. There was a weak association between biological yield (total above-ground dry weight) and grain yield.
It is suggested that although much of the improvement in yield described here could be attributed to increased harvest index, the scope for further improvement in this character may be limited. Further yield improvements might be achieved by combining high biological yield with high harvest index.
This paper briefly describes the principle of operation and science goals of the AMANDA high energy neutrino telescope located at the South Pole, Antarctica. Results from an earlier phase of the telescope, called AMANDA-BIO, demonstrate both reliable operation and the broad astrophysical reach of this device, which includes searches for a variety of sources of ultrahigh energy neutrinos: generic point sources, Gamma-Ray Bursts and diffuse sources. The predicted sensitivity and angular resolution of the telescope were confirmed by studies of atmospheric muon and neutrino backgrounds. We also report on the status of the analysis from AMANDA-II, a larger version with far greater capabilities. At this stage of analysis, details of the ice properties and other systematic uncertainties of the AMANDA-II telescope are under study, but we have made progress toward critical science objectives. In particular, we present the first preliminary flux limits from AMANDA-II on the search for continuous emission from astrophysical point sources, and report on the search for correlated neutrino emission from Gamma Ray Bursts detected by BATSE before decommissioning in May 2000. During the next two years, we expect to exploit the full potential of AMANDA-II with the installation of a new data acquisition system that records full waveforms from the in-ice optical sensors.
The progress that has been made in SiC diodes and GTOs is reviewed. A 100 A/1000 V SiC pi- n diode package, the highest current rating reported for any SiC device, a 69 A conduction/ 11 A turn-off of a SiC GTO and MTOTM, as well as the first all-SiC, 3 phase Pulse Width Modulated (PWM) inverter are reported, herein, for the first time. The inverter achieves voltage controlled turn off with a high temperature capable, hybrid SiC JFET. Material and process technology issues that will need to be addressed before device commercialization can be realized are discussed.