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We present ALMA band 7 data of the extreme OH/IR star, OH 26.5+0.6. In addition to lines of CO and its isotopologues, the circumstellar envelope also exhibits a number of emission lines due to metal-containing molecules, e.g., NaCl and KCl. A lack of C18O is expected, but a non-detection of C17O is puzzling given the strengths of H217O in Herschel spectra of the star. However, a line associated with Si17O is detected. We also report a tentative detection of a gas-phase emission line of MgS. The ALMA spectrum of this object reveals intriguing features which may be used to investigate chemical processes and dust formation during a high mass-loss phase.
Depression and metabolic syndrome (MetS) are frequently comorbid disorders that are independently associated with premature mortality. Conversely, cardiorespiratory fitness (CRF) is associated with reduced mortality risk. These factors may interact to impact mortality; however, their effects have not been assessed concurrently. This analysis assessed the mortality risk of comorbid depression/MetS and the effect of CRF on mortality in those with depression/MetS.
Prospective study of 47 702 adults in the Cooper Center Longitudinal Study. Mortality status was attained from the National Death Index. History of depression was determined by patient response (yes or no) to a standardized medical history questionnaire. MetS was categorized using the American Heart Association/National Heart, Lung, and Blood Institute criteria. CRF was estimated from the final speed/grade of a treadmill graded exercise test.
13.9% reported a history of depression, 21.4% met criteria for MetS, and 3.0% met criteria for both MetS and history of depression. History of depression (HR = 1.24, p = 0.003) and MetS (HR = 1.28, p < 0.001) were independently associated with an increased mortality risk, with the greatest mortality risk among individuals with both a history of depression and MetS (HR = 1.59, p < 0.001). Higher CRF was associated with a significantly lower risk of mortality (p < 0.001) in all individuals, including those with MetS and/or a history of depression.
Those with higher levels CRF had reduced mortality risk in the context of depression/MetS. Interventions that improve CRF could have substantial impact on the health of persons with depression/MetS.
Supernova (SN) 1987A has provided a unique opportunity to study how SN ejecta evolve in 30 years time scale. We report our ALMA spectral observations of SN 1987A, taken in 2014, 2015 and 2016, with detections of CO, 28SiO, HCO+ and SO, with weaker lines of 29SiO.
We find a dip in the SiO line profiles, suggesting that the ejecta morphology is likely elongated. The difference of the CO and SiO line profiles is consistent with hydrodynamic simulations, which show that Rayleigh-Taylor instabilities causes mixing of gas, with heavier elements much more disturbed, making more elongated structure.
Using 28SiO and its isotopologues, Si isotope ratios were estimated for the first time in SN 1987A. The estimated ratios appear to be consistent with theoretical predictions of inefficient formation of neutron rich atoms at lower metallicity, such as observed in the Large Magellanic Cloud (about half a solar metallicity).
The deduced large HCO+ mass and small SiS mass, which are inconsistent to the predictions of chemical model, might be explained by some mixing of elements immediately after the explosion. The mixing might have made some hydrogen from the envelope to sink into carbon and oxygen-rich zone during early days after the explosion, enabling the formation of a substantial mass of HCO+. Oxygen atoms may penetrate into silicon and sulphur zone, suppressing formation of SiS.
Our ALMA observations open up a new window to investigate chemistry, dynamics and explosive-nucleosynthesis in supernovae.
The development of the helium ion microscope (HIM) enables the imaging of both hard, inorganic materials and soft, organic or biological materials. Advantages include outstanding topographical contrast, superior resolution down to <0.5 nm at high magnification, high depth of field, and no need for conductive coatings. The instrument relies on helium atom adsorption and ionization at a cryogenically cooled tip that is atomically sharp. Under ideal conditions this arrangement provides a beam of ions that is stable for days to weeks, with beam currents in the order of picoamperes. Over time, however, this stability is lost as gaseous contamination builds up in the source region, leading to adsorbed atoms of species other than helium, which ultimately results in beam current fluctuations. This manifests itself as horizontal stripe artifacts in HIM images. We investigate post-processing methods to remove these artifacts from HIM images, such as median filtering, Gaussian blurring, fast Fourier transforms, and principal component analysis. We arrive at a simple method for completely removing beam current fluctuation effects from HIM images while maintaining the full integrity of the information within the image.
Aim: To examine cortical activation during a memory task in children with and without post-concussion symptoms (PCS) following concussion. Methods: A case-controlled study within the PlayGame Trial (www.playgametrial.ca). Children (aged 8-18 years) with PCS at 1-month post-injury were eligible. The fMRI task was a working memory task. Pre-processing and single-subject analysis were performed in FSL. Group activation and inter-group difference maps were extracted. Results: 11 symptomatic, 12 asymptomatic, and 11 controls without concussion participated. Groups were similar in age (14.9, 14.0, and 13.8yrs; p=0.46), sex (p=0.984) and time post-injury (symptomatic: 37d; asymptomatic 35d; p=0.573). Compared with controls, symptomatic children demonstrated greater activation especially in the bilateral orbito-frontal cortex and cerebellum. A similar, less pronounced pattern was observed in asymptomatic subjects. Conclusions: Similar to adult studies, increased network activation may represent decreased “efficiency” and explain the cognitive fatigue in PCS. Further, children who are “asymptomatic” may not yet be fully recovered.
An investigation of the bacterial flora in over 200 homes is reported. The occurrence of potential pathogens and the levels of contamination at individual sites, particularly in the kitchen, toilet and bathroom is described and the implications for hygiene practices in the home discussed.
An ‘in use’ test was developed to investigate effectiveness of disinfectant application and of detergent of hot water cleaning at kitchen, bathroom and toilet sites in the domestic environment. Detergent and hot water cleaning produced no observable reduction in microbial contamination. Single and daily application tests demonstrated that hypochlorite and phenolic disinfectants can be used to produce substantial reductions in bacterial contaminationin the home. Results indicate that maximum protection afforded by disinfection is relatively brief; 3–6 h after disinfection, contamination levels were only marginally less than those observed at pretreatment. Some suggestions are made for improvements in home hygiene.
We have examined karyotypes of five species from five genera of cyprinid fishes endemic to the central and southeastern United States: Campostoma anomalum, Hybognathus hayi, Hybopsis aestivalis, Phenacobius mirabilis, and Pimephales vigilax. All five have a diploid chromosome number of 50. Variation in chromosome arm number among the five species is slight, and may be due to measurement error or technique difficulties. The karyotypes of 40 North American cyprinids are now known. All but five species have 50 (diploid) chromosomes. Variation in chromosome arm number also appears minimal; one-armed chromosomes (centromeres subterminal to terminal) normally comprise only a small fraction of the karyotype, and each species has roughly the same number of chromosomes with median and submedian centromeres. The conservatism of gross chromosomal evolution among these fishes is not in accord with recent hypotheses which suggest that progressive evolution of organisms may depend to a large degree on gene rearrangement brought about by gross chromosomal restructuring. Cyprinids are a highly speciose group in North America, and there is relatively strong morphological differentiation among species. The present data suggest that gross chromosomal restructuring may play only a minor role in the speciation and evolution of these fishes.
A new, patent-pending method of cooling high-power laser diode arrays has been developed which leverages advances in several areas of materials science and manufacturing. This method utilizes multi-layer ceramic microchannel coolers with small (100's of microns) integral water channels to cool the laser diode bar. This approach is similar to the current state-of-the-art method of cooling laser diode bars with copper microchannel coolers. However, the multi-layer ceramic coolers offer many advantages over the copper coolers, including reliability and manufacturing flexibility. The ceramic coolers do not require the use of deionized water as is mandatory of high-thermal-performance copper coolers.
Experimental and modeled data is presented that demonstrates thermal performance equal to or better than copper microchannel coolers that are commercially available. Results of long-term, high-flow tests are also presented to demonstrate the resistance of the ceramic coolers to erosion. The materials selected for these coolers allow for the laser diode bars to be mounted using eutectic AuSn solder. This approach allows for maximum solder bond integrity over the life of the part.
Pregnancy outcome and characteristics of women who conceive following subfertility treatment remains a subject of great interest. We analyzed these variables among 199 women who delivered a registerable twin birth compared with 1773 women who delivered a naturally conceived twin birth in a population-based obstetric cohort drawn from around Oxford, England. Treatment was restricted to conceptions involving simple ovulation induction only. Treated mothers were of significantly higher social class and older, more likely to deliver girls and to be delivered by cesarean section, and significantly less likely to be smokers at the time of antenatal booking and to have delivered previous pregnancies. Pregnancy outcome was similar between the two groups for most measures, with the exception of birthweight which was lower in treated twins, though not significantly so. Overall the results are reassuring with respect to outcome in twin pregnancies following simple ovulation induction.
INTEGRAL is the first gamma-ray astronomy mission with a sufficient sensitivity and angular resolution combination appropriate to the detection and identification of considerable numbers of gamma-ray emitting sources. The large field of view enables INTEGRAL to survey the Galactic Plane on a regular ($\sim$weekly) basis as part of the core programme. The first source catalogue, based on the 1st year of core programme data ($\sim$5 Msec) has been completed and published (Bird et al. 2004). It contained 123 $\gamma$-ray sources (24 HMXB, 54 LMXB, 28 “unknown”, plus 17 others) - sufficient numbers for a reasonable statistical analysis of their global properties. The detection of previously unknown $\gamma$-ray emitting sources generally exhibiting high intrinsic absorption, which do not have readily identifiable counterparts at other wavelengths, is intriguing. The substantial fraction of unclassified $\gamma$-ray sources suggests they must constitute a significant family of objects. In this paper we review the global characteristics of the known galactic sources as well as the unclassified objects.
We report the discovery of carbonates in the Planetary Nebulae NGC 6302 and NGC 6537 (Kemper et al. 2002). In the ISO LWS spectra far-infrared features have been identified with calcite and dolomite by comparison with laboratory spectra of these minerals. This is the first time that carbonates have been identified outside the solar system. In a follow-up study (Kemper et al., in prep.) a detailed analysis of the mineral composition of the dust in NGC 6302 is presented.
As contribution to a recent debate (James, 1998; Murphy et al., 1997, 1998) the proportion of twins following ovulation induction (OI) or assisted conception (AC) in 1994 in Oxfordshire and West Berkshire was estimated, and by extrapolation the natural twinning rate in England and Wales was judged to have maintained a plateau phase since the 1970s. Similar figures for 1995 and 1996 from the same study, and hence a more stable local estimate, are now provided. The proportions, as before, were estimated from women's responses to a questionnaire within a case-control study, with ascertainment from general practitioners' records or hospital case-notes for non-responders or for those excluded from the study originally. In 1994, 1995 and 1996 the proportion of twins following OI/AC was overall 27% (24%, 30% and 27% respectively). Restriction to the 87% locally resident made no difference. The national crude twinning rate for those years was overall 13·3 per 1000 maternities (12·8, 13·6 and 13·4 respectively).
We consider a class of fractal subsets of
formed in a manner analogous to the construction of the Sierpinski carpet. We prove a uniform Harnack inequality for positive harmonic functions; study the heat equation, and obtain upper and lower bounds on the heat kernel which are, up to constants, the best possible; construct a locally isotropic diffusion $X$ and determine its basic properties; and extend some classical Sobolev and Poincaré inequalities to this setting.
Milk yield was determined by the weigh-suckle-weigh method over
2 years (1983 and 1984 calvings),
for a total of 305 purebred Hereford (H×H) and first-cross
Simmental×Hereford (S×H) and Friesian×Hereford (F×H)
cows grazing three pasture systems at
Grafton, New South Wales, Australia. The age of the cows ranged from
6 to 11 years. The data were
used to evaluate different estimates of milk yield and to examine
the effects of milk yield on growth of calves up to weaning.
Of all the cow traits studied, average lactation milk yield (average of
early, mid and late-lactation
milk yields) had the highest correlation coefficient with calf 210-day
weight (r=0·73) and pre-weaning average daily gain
(ADGtotal, r=0·73), and explained >50% of the
variation in the calf
traits. However, milk yield was also moderately correlated with other cow traits
(liveweight and body
condition score). Thus, to predict calf performance, milk yield data may not
be required if detailed
data on other cow traits are available. This is supported by the finding that
differences in the coefficients of determination (R2)
between models for calf 210-day weight and ADGtotal which
included average lactation milk yield and other cow traits (highest
R2=69%) and models which
included other cow traits but no milk yield estimate (highest
R2=57%) were <13%.
Cow breed rankings for average lactation milk yield were similar
to those for calf 210-day weight
and ADGtotal. On high quality pasture, S×H and F×H cows produced
the most milk (S×H,
7·5 kg/day; F×H, 8·3 kg/day; B×H,
H×H, 5·5 kg/day) and weaned the heaviest calves
(S×H, 255 kg; F×H, 252 kg; B×H, 215 kg;
H×H, 217 kg), while on low quality pasture, B×H
and F×H cows produced the most milk (B×H,
4·2 kg/day; F×H, 3·7 kg/day; S×H,
H×H, 2·7 kg/day) but B×H cows weaned the heaviest
calves (B×H, 180 kg; F×H, 168 kg; S×H,
159 kg; H×H, 124 kg).
Hereford (H × H), Brahman × Hereford (B × H), Simmental × Hereford (S × H) and Friesian × Hereford (F × H) females born over a 5-year period (1973–77) were placed on pastures of high, medium or low nutritive value at Grafton, New South Wales, Australia, at weaning (7–8 months of age). The first mating of heifers on high pasture was at 15 months (1974) while that on medium and low pastures was delayed until 27 months of age (1975). This paper reports the reproductive performance of these cows up to 5 years of age and the preweaning growth of their calves which were sired by Hereford bulls at Grafton, Australia. In total, 1222 calving records were analysed.
Most traits were subject to interaction between genotype and other main effects (pasture, year of birth of cow, cow age and sex of calf). Eyelid pigmentation was an exception, with calves from B × H cows having more than calves of other genotypes (73 v. 43%). There were significant genotype differences in calving difficulty among 2-year-old heifers only, with H × H (33%) requiring more assistance than F × H (15%) and SxH (10%) heifers, while B × H heifers did not require any assistance. Genotype differences in percentage of calves born and weaned were observed on low pastures only, where B × H (66% born, 65% weaned) exceeded H × H (48%, 39%) and S × H (39%, 38%) cows, with F × H (58%, 50%) cows being intermediate. Calves by H × H cows were the slowest-growing and were the lightest at weaning on all pastures, with mean gains of 759, 604 and 340 g/day, and mean weaning weights of 212, 188 and 110 kg, on high, medium and low quality pastures, respectively. F × H and S × H cows produced the fastest-growing calves on high quality pasture (966 and 936 g/day, respectively) while B × H cows produced the fastest-growing calves on medium (823 g/day) and low (679 g/day) quality pastures. F × H cows weaned the heaviest calves on high quality pasture (274 kg) while F × H and B × H weaned the heaviest calves on medium (230 and 229 kg, respectively) and low (162 and 169 kg, respectively) quality pastures. Differences in body measurements followed a pattern similar to weaning weight.
The preweaning growth of the progeny of mature cows grazing high, medium or low quality pasture was evaluated. The cows were 5–9 years of age at the beginning of the study and were either purebred Hereford (H x H), first-cross Brahman x Hereford (B x H), Simmental x Hereford (S x H) or Friesian x Hereford (F x H). Hereford and Brahman bulls were mated to these cows for three mating seasons commencing in 1982, at Grafton, New South Wales, Australia. Records on 634 calves born over three consecutive years were used.
Most traits were subject to significant sire breed or dam breed effects or their interactions with one or more of the other main effects (pasture, year of birth of calf, cow age and sex of calf). The incidences of calving difficulty and stillbirths were exceptions. Stillbirths (mean of 3·8%) were not affected by any of the effects studied, while calving difficulty was affected only by sex of calf effect (males, 3·9%; females, 0·8%). The mean calving date of Brahman-sired calves was 11·4 days later (P < 0·05) than that of Hereford-sired calves. Differences between Brahman-sired and Hereford-sired calves for weaning weight were not significant for S x H (Brahman, 237 kg; Hereford, 232 kg) and FxH (Brahman, 238kg; Hereford, 238kg) dams. For HxH dams however, calves sired by Brahman were heavier at weaning (205 kg) than those sired by Hereford (193 kg) bulls, while for B x H dams the reverse was true (Brahman, 222 kg; Hereford, 231 kg). For calves with B x H dams average daily gain (ADG) was the same (957 g/day) for each sire breed, while for the other dam breeds, Brahman-sired calves had a higher ADG than Hereford-sired calves (862 v. 779, 1014 v. 946 and 1022 v. 950 g/day for H x H, S x H and FxH, respectively). Calves sired by Brahman bulls had > 90% eyelid pigmentation while Hereford-sired calves had 44–74%. On high quality pasture, the weaning weights and ADG of calves of F x H and S x H dams were higher than those of B x H and HxH dams. On medium quality pasture, weaning weight of calves of crossbred dams (B x H, S x H and FxH) were similar but higher than those of H x H dams. On low quality pasture, mean weaning weight of calves of B x H was higher than those of S x H and F x H dams, which in turn, were higher than that of H x H dams.