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Gravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, which depend on the neutron star equation of state. Neutron star mergers are expected to often produce rapidly rotating remnant neutron stars that emit gravitational waves. These will provide clues to the extremely hot post-merger environment. This signature of nuclear matter in gravitational waves contains most information in the 2–4 kHz frequency band, which is outside of the most sensitive band of current detectors. We present the design concept and science case for a Neutron Star Extreme Matter Observatory (NEMO): a gravitational-wave interferometer optimised to study nuclear physics with merging neutron stars. The concept uses high-circulating laser power, quantum squeezing, and a detector topology specifically designed to achieve the high-frequency sensitivity necessary to probe nuclear matter using gravitational waves. Above 1 kHz, the proposed strain sensitivity is comparable to full third-generation detectors at a fraction of the cost. Such sensitivity changes expected event rates for detection of post-merger remnants from approximately one per few decades with two A+ detectors to a few per year and potentially allow for the first gravitational-wave observations of supernovae, isolated neutron stars, and other exotica.
Maintaining nutritional adequacy contributes to successful ageing. B vitamins involved in one carbon metabolism regulation (folate, riboflavin, vitamins B6 and B12) are critical nutrients contributing to homocysteine and epigenetic regulation, and DNA synthesis. Although cross-sectional B vitamin intake has been characterised in various ageing populations, longitudinal changes are infrequently reported. This systematic review explores age-related changes in dietary adequacy of folate, riboflavin, vitamins B6 and B12 in community-dwelling older adults (≥65 years at follow-up). Following PRISMA guidelines, relevant databases (Medline, EMBASE, Biosis, CINAHL) were systematically screened, yielding 1579 records; 8 studies were included (n = 3119 participants, 2-25 years of follow-up). Quality assessment using a modified Newcastle-Ottawa quality scale rated all studies of moderate-high quality. The estimated average requirement cut-point method estimated the baseline and follow-up population prevalence of dietary inadequacy. Notably, riboflavin (7 studies, n=1953) inadequacy appears to progressively increase with age, with the prevalence of inadequacy increasing from baseline by up to 22.6% and 9.3% in males and females, respectively. Dietary folate adequacy (3 studies, n=2321) improved in two studies (by up to 22.4%), but the third showed increasing (8.1%) inadequacy. Evidence was similarly limited (2 studies respectively) and inconsistent for changes in dietary inadequacy of vitamins B6 (n=559; -9.9 – 47.9%) and B12 (n=1410; -4.6 – 7.2%). This review emphasises the scarcity of evidence regarding micronutrient intake changes with age, and highlights the demand for improved reporting of longitudinal changes in nutrient intake that can better direct micronutrient recommendations for older adults. This review was registered with Prospero (CRD42018104364).
Diet has a major influence on the composition and metabolic output of the gut microbiome. Higher-protein diets are often recommended for older consumers; however, the effect of high-protein diets on the gut microbiota and faecal volatile organic compounds (VOC) of elderly participants is unknown. The purpose of the study was to establish if the faecal microbiota composition and VOC in older men are different after a diet containing the recommended dietary intake (RDA) of protein compared with a diet containing twice the RDA (2RDA). Healthy males (74⋅2 (sd 3⋅6) years; n 28) were randomised to consume the RDA of protein (0⋅8 g protein/kg body weight per d) or 2RDA, for 10 weeks. Dietary protein was provided via whole foods rather than supplementation or fortification. The diets were matched for dietary fibre from fruit and vegetables. Faecal samples were collected pre- and post-intervention for microbiota profiling by 16S ribosomal RNA amplicon sequencing and VOC analysis by head space/solid-phase microextraction/GC-MS. After correcting for multiple comparisons, no significant differences in the abundance of faecal microbiota or VOC associated with protein fermentation were evident between the RDA and 2RDA diets. Therefore, in the present study, a twofold difference in dietary protein intake did not alter gut microbiota or VOC indicative of altered protein fermentation.
We describe 14 yr of public data from the Parkes Pulsar Timing Array (PPTA), an ongoing project that is producing precise measurements of pulse times of arrival from 26 millisecond pulsars using the 64-m Parkes radio telescope with a cadence of approximately 3 weeks in three observing bands. A comprehensive description of the pulsar observing systems employed at the telescope since 2004 is provided, including the calibration methodology and an analysis of the stability of system components. We attempt to provide full accounting of the reduction from the raw measured Stokes parameters to pulse times of arrival to aid third parties in reproducing our results. This conversion is encapsulated in a processing pipeline designed to track provenance. Our data products include pulse times of arrival for each of the pulsars along with an initial set of pulsar parameters and noise models. The calibrated pulse profiles and timing template profiles are also available. These data represent almost 21 000 h of recorded data spanning over 14 yr. After accounting for processes that induce time-correlated noise, 22 of the pulsars have weighted root-mean-square timing residuals of
in at least one radio band. The data should allow end users to quickly undertake their own gravitational wave analyses, for example, without having to understand the intricacies of pulsar polarisation calibration or attain a mastery of radio frequency interference mitigation as is required when analysing raw data files.
Surveillance for acute flaccid paralysis (AFP) cases are essential for polio eradication. However, as most poliovirus infections are asymptomatic and some regions of the world are inaccessible, additional surveillance tools require development. Within England and Wales, we demonstrate how inclusion of environmental sampling (ENV) improves the sensitivity of detecting both wild and vaccine-derived polioviruses (VDPVs) when compared to current surveillance. Statistical modelling was used to estimate the spatial risk of wild and VDPV importation and circulation in England and Wales. We estimate the sensitivity of each surveillance mode to detect poliovirus and the probability of being free from poliovirus, defined as being below a pre-specified prevalence of infection. Poliovirus risk was higher within local authorities in Manchester, Birmingham, Bradford and London. The sensitivity of detecting wild poliovirus within a given month using AFP and enterovirus surveillance was estimated to be 0.096 (95% CI 0.055–0.134). Inclusion of ENV in the three highest risk local authorities and a site in London increased surveillance sensitivity to 0.192 (95% CI 0.191–0.193). The sensitivity of ENV strategies can be compared using the framework by varying sites and the frequency of sampling. The probability of being free from poliovirus slowly increased from the date of the last case in 1993. ENV within areas thought to have the highest risk improves detection of poliovirus, and has the potential to improve confidence in the polio-free status of England and Wales and detect VDPVs.
We describe an ultra-wide-bandwidth, low-frequency receiver recently installed on the Parkes radio telescope. The receiver system provides continuous frequency coverage from 704 to 4032 MHz. For much of the band (
), the system temperature is approximately 22 K and the receiver system remains in a linear regime even in the presence of strong mobile phone transmissions. We discuss the scientific and technical aspects of the new receiver, including its astronomical objectives, as well as the feed, receiver, digitiser, and signal processor design. We describe the pipeline routines that form the archive-ready data products and how those data files can be accessed from the archives. The system performance is quantified, including the system noise and linearity, beam shape, antenna efficiency, polarisation calibration, and timing stability.
The recognition of ‘fetal origins of adult disease’ has placed new responsibilities on the obstetrician, as antenatal care is no longer simply about ensuring good perinatal outcomes, but also needs to plan for optimal long-term health for mother and baby. Recently, it has become clear that the intrauterine environment has a broad and long-lasting impact, influencing fetal and childhood growth and development as well as future cardiovascular health, non-communicable disease risk and fertility. This article looks specifically at the importance of the developmental origins of ovarian reserve and ageing, the role of the placenta and maternal nutrition before and during pregnancy. It also reviews recent insights in developmental medicine of relevance to the obstetrician, and outlines emerging evidence supporting a proactive clinical approach to optimizing periconceptional as well as antenatal care aimed to protect newborns against long-term disease susceptibility.
Although cognitive deficits are common in patients with chronic heart failure (CHF), no study to date has investigated whether these deficits extend to the capacity to execute delayed intentions (prospective memory, PM). This is a surprising omission given the critical role PM plays in correctly implementing many important CHF self-care behaviors. The present study aimed to provide the first empirical assessment of PM function in people with CHF. The key dependent measure was a laboratory measure of PM that closely simulates PM tasks in daily life – Virtual Week. A group comparison design was used, with 30 CHF patients compared to 30 demographically matched controls. Background measures assessing executive functions, working memory, and verbal memory were also administered. The CHF group exhibited significant PM impairment, with difficulties generalizing across different types of PM tasks (event, time, regular, irregular). The CHF group also had moderate deficits on several of the background cognitive measures. Given the level of impairment remained consistent even on tasks that imposed minimal demands on memory for task content, CHF-related difficulties most likely reflects problems with the prospective component. However, exploratory analyses suggest that difficulties with retrospective memory and global cognition (but not executive control), also contribute to the PM difficulties seen in this group. The implications of these data are discussed, and in particular, it is argued that problems with PM may help explain why patient engagement in CHF self-care behaviors is often poor. (JINS, 2015, 21, 1–10)
Feeding n-3 long-chain polyunsaturated fatty acids (LCPUFA) to gilts or sows has shown different responses to litter growth, pre-weaning mortality and subsequent reproductive performance of the sow. Two hypotheses were tested: (1) that feeding a marine oil-based supplement rich in protected n-3 LCPUFAs to gilts in established gestation would improve the growth performance of their litters; and (2) that continued feeding of the supplement during lactation and after weaning would offset the negative effects of lactational catabolism induced, using an established experimental model involving feed restriction of lactating primiparous sows. A total of 117 primiparous sows were pair-matched at day 60 of gestation by weight, and when possible, litter of origin, and were allocated to be either control sows (CON) fed standard gestation and lactation diets, or treated sows (LCPUFA) fed the standard diets supplemented with 84 g/day of a n-3 LCPUFA rich supplement, from day 60 of first gestation, through a 21-day lactation, and until euthanasia at day 30 of their second gestation. All sows were feed restricted during the last 7 days of lactation to induce catabolism, providing a background challenge against which to determine beneficial effects of n-3 LCPUFA supplementation on subsequent reproduction. In the absence of an effect on litter size or birth weight, n-3 LCPUFA tended to improve piglet BW gain from birth until 34 days after weaning (P = 0.06), while increasing pre-weaning mortality (P = 0.05). It did not affect energy utilization by the sow during lactation, thus not improving the catabolic state of the sows. Supplementation from weaning until day 30 of second gestation did not have an effect on embryonic weight, ovulation rate or early embryonic survival, but did increase corpora lutea (CL) weight (P = 0.001). Eicosapentaenoic acid and docosahexaenoic acid (DHA) levels were increased in sow serum and CL (P < 0.001), whereas only DHA levels increased in embryos (P < 0.01). In conclusion, feeding n-3 LCPUFA to gilts tended to improve litter growth, but did not have an effect on overall subsequent reproductive performance.
Titanium and its alloys have been employed in bone plates/screws, and these
are often designed to be removed after recovery. Bone is known to bond to
the surface of Ti alloys. This can lead to re-fracture of newly repaired
bone during operations to remove the implants, however bone does not bond to
Zr-based alloys. The inhibition of bone conduction on the surface of
Zr-based alloys is thought to be due to the presence of a thin layer of
zirconia (ZrO2) on the surface. The purpose of the present study
was to synthesize bioinert films, including ZrO2 on pure Ti
surfaces. In vitro apatite (HAp) formation and in
vivo bone conduction in the tibiae of rats on the films were
Commercial purity Ti was chemically treated with aqueous
H2O2/HNO3 at 353 K for 20 min. The disks
were hydrothermally treated with aqueous
(citric acid) in an autoclave at 453 K for 12 h. Simulated body fluid (SBF)
immersion test and implantation into tibiae of rats were carried out.
In the hydrothermal treatment with aqueous ZrOCl2/NH3,
the surface product was anatase-type TiO2. On the other hand,
when citric acid was added the surface of Ti was covered homogeneously with
a TiO2–ZrO2 composite film though the amount of
ZrO2 was very small. HAp began to form on the non-modified Ti
and TiO2 surfaces after 6 days and 4 days immersion in Hank’s
solution, respectively. On the surfaces of TiO2–ZrO2,
the presence of precipitates was confirmed after 6-8 days. The HAp formation
was suppressed on the surfaces of TiO2–ZrO2.The
present TiO2-ZrO2 surface also showed significantly
lower bone-implant contact ratio in cortical bone compared with
To determine risk factors for cholera in an epidemic-disease area in South America, a case–control investigation was performed in Guayaquil, Ecuador, in July 1991. Residents > 5 years old who were hospitalized for treatment of acute, watery diarrhoea and two matched controls for each were interviewed regarding sources of water and food, and eating, drinking, and hygienic habits. Interviewers inspected homes of case-patients and controls to document water treatment, food-handling, and hygienic practices. Faecal specimens and shellfish were cultured for Vibrio cholerae O 1. Isolates were tested for susceptibility to a variety of antimicrobial agents. Drinking unboiled water (odds ratio [OR] = 4.0, confidence interval [CI] = 1.8–7.5), drinking a beverage from a street vendor (OR = 2.8, CI = 1.3–5.9), eating raw seafood (OR = 3.4, CI = 1.4–11.5), and eating cooked crab (OR = 5.1, CI = 1.4–19.2) were associated with illness. Always boiling drinking water at home (OR = 0.5, CI = 0.2–0.9) was protective against illness. The presence of soap in either the kitchen (OR = 0.3, CI = 0.2–0.8) or bathroom (OR = 0.4, CI = 0.2–0.9) at home was also protective. V. cholerae O 1 was recovered from a pooled sample of a bivalve mollusc and from 68% of stool samples from case-patients. Thirty-six percent of the isolates from stool specimens were resistant to multiple antimicrobial agents. Specific prevention measures may prevent transmission through these vehicles in the future. The appearance of antimicrobial resistance suggests the need for changes in current methods of prevention and treatment.
Epidemic cholera reached Guatemala in July 1991. By mid-1993, Guatemala ranked third in the hemisphere in reported cases of cholera. We conducted a case-control study with two age-, sex-, and neighbourhood-matched controls per patient in periurban Guatemala City. Twenty-six patients hospitalized for cholera and 52 controls were enrolled. Seven (47%) of 15 stool cultures obtained after admission yielded toxigenic Vibrio cholerae Ol. All seven were resistant to furazolidone, sulfisoxazole, and streptomycin, and differed substantially by pulsed-field gel electrophoresis from the Latin American epidemic strain dominant in the hemisphere since 1991. In univariate analysis, illness was associated with consumption of left-over rice (odds ratio [OR] = 7·0, 95% confidence interval [CI] = 1·4–36), flavored ices (‘helados’) (OR = 3·6, CI = 1·1–12), and street-vended non-carbonated beverages (OR = 3·8, CI = 1·2–12) and food items (OR = 11·0, CI = 2·3–54). Street-vended food items remained significantly associated with illness in multivariate analysis (OR = 6·5, CI = 1·4–31). Illness was not associated with drinking municipal tap water. Maintaining water safety is important, but slowing the epidemic in Guatemala City and elsewhere may also require improvement in street vendor food handling and hygiene.
BMI is commonly used as a sole indicator for the assessment of nutritional status. While it is a good predictor of morbidity and mortality among young and middle-aged adults, its predictive ability among the oldest old remains unclear. The objective of the present study was to investigate the relationship between BMI and risk of falls, fractures and all-cause mortality among older Australians in residential aged care facilities. One thousand eight hundred and forty-six residents of fifty-two nursing homes and thirty hostels in northern Sydney, Australia, participated in the present study. Baseline weight and height were measured and BMI (kg/m2) calculated. For 2 years following the baseline measurements, incidence and date of all falls and fractures were recorded by research nurses who visited the facilities regularly and date of death was documented based on the participants' records at each facility. Cox proportional hazards regression models were calculated to determine the relationship between baseline BMI and time to fall, fracture or death, within 2 years following the baseline measures taken to be the censoring date. After adjustments were made for age, sex and level of care, low BMI ( < 22 kg/m2) increased the risk of fracture by 38 % (hazard ratio = 1·38, 95 % CI 1·11, 1·73) and all-cause mortality by 52 % (hazard ratio = 1·52, 95 % CI 1·30, 1·79). The magnitude of this effect was only slightly reduced when adjustments were further made to incorporate cognition, number of medications, falls and fracture in the subsequent 2-year period. In conclusion, BMI has predictive ability in the area of fracture and all-cause mortality for residents of aged care facilities. It is a simple and rapid indicator of nutritional status rendering it a useful nutrition screen and goal for nutrition intervention.
Abstract Acute phase proteins (APP) are released into the circulation in mammals upon infection and may be used to diagnose the health status of managed populations of animals such as pigs. The current study determines APP levels in a population of apparently healthy Large White pigs from a single farm, to address two questions: (1) whether phenotypic associations can be observed between productivity and APP, indicating the effects of possible subclinical infections and (2) whether previous selection for either food intake or ‘lean growth under restricted feeding’ influences APP levels. The APP investigated were alpha1- acid glycoprotein (AGP) and haptoglobin. The APP were measured at 18 and 24 weeks of age in pigs previously selected for high lean growth (no. = 31), low lean growth (no. = 38), high daily food intake (no. = 24) and low daily food intake (no. = 26), but performing under ad libitum feeding conditions. Performance traits and APP levels were constant over the experimental period, indicating that the farm health status did not vary over time. Performance traits and APP were recorded on 119 pigs, of which 80 had both APP and performance measurements. Multiple regression analyses were used to investigate phenotypic relationships between performance traits and APP levels. Plasma concentrations of AGP were higher in 18-week-old pigs compared with 24-week-old pigs (P < 0·01) whereas haptoglobin levels did not vary according to age. Significant sex differences in APP levels were observed. Females had higher circulating levels of AGP than males at both 18 weeks and 24 weeks. Females also had higher levels of haptoglobin at 18 weeks. Levels of AGP had significant negative correlations with daily weight gain (−0·59, P < 0·01 and −0·48, P < 0·05 at 18 and 24 weeks respectively) and with daily food intake (−0·53, P < 0·01 and −0·38, P < 0·05 at 18 and 24 weeks respectively). At age 24 weeks, haptoglobin was negatively correlated with both daily weight gain (−0·35, P < 0·05) and food efficiency (−0·34, P < 0·05). Pigs selected for high lean growth under restricted feeding had higher AGP levels than pigs selected for low lean growth under restricted feeding at 18 (593 v. 332 μg/ml, P < 0·01) and 24 weeks of age (313 v. 219 μg/ml, P < 0·05). Selection for daily food intake did not consistently affect AGP levels, and neither selection criteria influenced plasma haptoglobin concentrations. To conclude, we have demonstrated that amongst contemporaneous pigs of the same genotype, higher systemic AGP levels and, to a lesser extent, higher haptoglobin levels are associated with decreased performance, and that genetic selection for ‘efficient lean growth under restricted feeding’ can increase serum AGP levels.
Productivity in pigs can be improved by continued selection, however the impact of such selection on immune responses and resistance towards infectious challenges is not known. A risk is that this method may lead to a correlated reduction in the immune response and disease resistance. To estimate the effect of selection for performance traits upon immune responses, we compared levels of immune traits between divergent lines of Large White pigs selected for either lean growth under restricted feeding or feed intake.
This paper describes the development of an approach to handling qualities investigation that can be applied at an early stage in t he design of the vehicle. It makes use of inverse simulation techniques, together with a pilot model to provide an integrated description of the man-machine control system. In order to incorporate pilot effects into data generated by inverse simulation, the output from an inverse simulation run is applied as input to a closed-loop system model that includes the vehicle dynamics and a simple parametric model of the pilot. Parameters of the pilot model are determined by optimisation and the pilot effect is added to the system output. Validation of the approach is achieved through a case study involving a predefined mission task involving a lateral manoeuvre. Equalisation characteristics estimated for each pilot are compared with those found by inverse simulation for the same manoeuvre. This approach may be applied using a simple real-time simulation on a desk-top computer and could be of value in identifying any potential deficiencies in a helicopter flight control system at an early stage in its development