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The effect of maternal Ramadan-type fasting (RTF) on the outcome of pregnancy, kidney development and nephron number in male rat offspring was investigated in current study. Pregnant rats were given food and water ad libitum during pregnancy (control) or restricted for 16 h per day (RTF). Kidney structure was examined during fetal life, at birth, and in early and late adulthood. Maternal body weight, food intake, relative food intake and plasma glucose levels were significantly lower (P<0.001) in the RTF group. Litter and pup weights also were significantly lower (P<0.05) in the RTF group at birth, with no difference in the litter size. The RTF group had a longer gestation, delayed nephrogenesis with less well-differentiated glomeruli, more connective tissue, fewer medullary rays, an increase in the nephrogenic zone/cortical zone ratio, and significant increase (P<0.001) in kidney apoptosis at birth. On the other hand, maternal fasting reduced nephron number (by ~31%) with unchanged kidney and total glomerular volumes. Mean glomerular volume was significantly higher in RTF offspring. Assessment of renal structure revealed mild glomerulosclerosis with enlarged lobulated glomeruli in the renal cortex and high interstitial fibrosis in the medulla of RTF kidneys. Taken together, gestational fasting delays nephrogenesis and reduces nephron number in the kidneys of the offspring, that could be partially owing to increased apoptosis.
Since April 2015, whole genome sequencing (WGS) has been the routine test for Salmonella identification, surveillance and outbreak investigation at the national reference laboratory in England and Wales. In May 2015, an outbreak of Salmonella Enteritidis cases was detected using WGS data and investigated. UK cases were interviewed to obtain a food history and links between suppliers were mapped to produce a food chain network for chicken eggs. The association between the food chain network and the phylogeny was explored using a network comparison approach. Food and environmental samples were taken from premises linked to cases and tested for Salmonella. Within the outbreak single nucleotide polymorphism defined cluster, 136 cases were identified in the UK and 18 in Spain. One isolate from a food containing chicken eggs was within the outbreak cluster. There was a significant association between the chicken egg food chain of UK cases and phylogeny of outbreak isolates. This is the first published Salmonella outbreak to be prospectively detected using WGS. This outbreak in the UK was linked with contemporaneous cases in Spain by WGS. We conclude that UK and Spanish cases were exposed to a common source of Salmonella-contaminated chicken eggs.
Accurate discrimination of two morphologically similar species of Patella limpets has been facilitated by using qPCR amplification of species-specific mitochondrial genomic regions. Cost-effective and non-destructive sampling is achieved using a mucus swab and simple sample lysis and dilution to create a PCR template. Results show 100% concurrence with dissection and microscopic analysis, and the technique has been employed successfully in field studies. The use of highly sensitive DNA barcoding techniques such as this hold great potential for improving previously challenging field assessments of species abundance.
Most of the recent advances in X-ray astronomy have resulted from satellite observations in the low energy (< 20 keV) range. The Einstein X-ray Observatory in particular has been responsible for a dramatic increase in our knowledge of the X-ray sky, in that all major classes of astronomical objects have been detected.
This study examined the socioeconomic pathways linking partnership status to physical functioning, assessed using objective measures of late life physical functioning, including peak flow and grip strength. Using Wave 4 of the Survey of Health, Ageing and Retirement in Europe (SHARE), we ran multilevel models to examine the relationship between partnership status and physical function in late life, adjusting for social-network characteristics, socioeconomic factors, and health behaviours. We found a robust relationship between partnership status and physical function. Incorporating social-network characteristics, socioeconomic factors, and health behaviours showed independent robust relationships with physical function. Co-variates attenuated the impact of cohabitation, separation, and widowhood on physical function; robust effects were found for singlehood and divorce. Sex-segregated analyses suggest that associations between cohabitation, singlehood, divorce, and widowhood were larger for men than for women. Results suggest that social ties are important to improved physical function.
Consumers’ willingness to pay for postharvest-processed (PHP) raw oysters—oysters without health risks—is studied in experimental auction markets. The experimental design decomposes the effects of taste, objective risk information, and information on four PHP technologies on consumer valuations. Results show that relatively uninformed consumers are willing to pay equivalent amounts for PHP and traditional raw oysters. However, after a blind taste test, consumers are willing to pay a significant premium for traditional raw oysters, and the premium persists after objective information on risk and processing technologies is provided. The results are robust across PHP technologies.
A community outbreak of legionellosis occurred in Barrow-in-Furness, Cumbria, during July and August 2002. A descriptive study and active case-finding were instigated and all known wet cooling systems and other potential sources were investigated. Genotypic and phenotypic analysis, and amplified fragment length polymorphism of clinical human and environmental isolates confirmed the air-conditioning unit of a council-owned arts and leisure centre to be the source of infection. Subsequent sequence-based typing confirmed this link. One hundred and seventy-nine cases, including seven deaths [case fatality rate (CFR) 3·9%] were attributed to the outbreak. Timely recognition and management of the incident very likely led to the low CFR compared to other outbreaks. The outbreak highlights the responsibility associated with managing an aerosol-producing system, with the potential to expose and infect a large proportion of the local population and the consequent legal ramifications and human cost.
Protandric oysters generate a relatively uniform reproductive potential over a wide range of environmental conditions that impose variations in growth rate and life span. Sex-at-length keys applied to survey data show that the female fraction routinely fell between 0.4 and 0.5, regardless of location in the salinity gradient. About 70% of population biomass is female over the same salinity range. Due to the necessary local modulation of the rate of male-to-female conversion to limit the influence of varying growth and life span over the salinity gradient, the number of males always exceeds by a small amount the number of females; thus improving the likelihood of a female having neighbouring males, a necessity for an immobile broadcast spawner. However, oysters at the extremes of the estuarine gradient all yielded populations with divergent sex-ratios. One consequence of reduced generation time brought about by increased mortality from disease should be selection favouring the switch from male to female at smaller size, if disease mortality is strongly female-biased. The site with the longest record of high mortality manifests such an increase. Sites up coastal rivers, putative refuges from disease, harbour animals with the slowest male-to-female conversion rates. Arguably these animals are most similar to the ancestral oyster pre-disease. Marketed animals range from 62% to 69% female. The principal influence of the fishery, and of oyster disease, would seem to be a reduction in lifetime egg production. Dermo disease may have reduced lifetime fecundity of females by nearly a factor of four.
This paper describes virological and epidemiological features of an infection which killed two of three affected cheetahs at Whipsnade Park in 1977. Two animals had profuse skin lesions and the third had an acute haemorrhagic pneumonia. The outbreak was shown to be caused by cowpox virus. Cowpox virus is believed to circulate in small wild animals, but the source of infection was not traced despite virological and serological tests on 93 captive and 102 wild animals.
Sub-clinical infections did not occur in susceptible contact cheetahs. Immune globulin did not influence the outcome and smallpox vaccine does not take in cheetahs. Management of any future outbreak will rely on prompt diagnosis and segregation of infected animals.
Skeletal muscle is a highly dynamic and malleable tissue that is able to adapt to different stimuli placed upon it, both during gestation and after birth, ultimately resulting in anatomical changes to muscle fibre composition. Variation in nutrient supply throughout gestation is common, whether in livestock or in the human. The specific effects of maternal nutrition on foetal development are at the forefront of scientific research. However, results describing how different maternal feeding strategies affect skeletal muscle fibre development in the offspring are not fully consistent, even where the same time windows during gestation have been examined. The aim of this study is to determine the effects of increased maternal nutrition (above the recommended levels) on the Musculus semitendinosus phenotype of progeny. In all, 24 pregnant sows were assigned to one of four feeding regimes during gestation; T1 (control group): 30 MJ digestible energy per day (MJ DE/day) throughout gestation, T2: same as that for T1 but increased to 60 MJ DE/day from 25 to 50 days of gestation (dg), T3: same as that for T1 but increased to 60 MJ DE/day from 50 to 80 dg, T4: same as that for T1 but increased nutrition to 60 MJ DE/day from 25 to 80 dg. Light- and heavy-weight littermate pairs of the same sex were selected at birth and individually fed to slaughter (c. 158 days). Histochemical and immunohistochemical staining were used to identify the predominantly oxidative (deep) and less oxidative (superficial) regions of the M. semitendinosus, and to determine total fibre number and proportions of fibre types. The results demonstrate that increased maternal nutrition alters skeletal muscle phenotype in the offspring by changing fibre-type proportions, leading to an increased oxidative capacity due to an increase in Type IIA fibres. No change in total muscle area, total muscle fibre number, or fibre cross-sectional area is observed. The precise molecular mechanism(s) by which these findings occur is being investigated.
Characteristics of the second gnathopod are traditionally used to distinguish between species of caprellid amphipods. However, these distinctions are often subjective and can be variable within a species. Geometric morphometrics were used to quantitatively assess shape variation of the second gnathopod propodus of three species of caprellids in North America, including the non-native Caprella mutica. Gnathopod shapes of C. mutica specimens from different latitudes revealed distinct morphologies; the factors responsible for the shape variations are unknown. Allometric change of propodus shape was observed in C. mutica. Larger individuals showed a wide array of possible propodus morphologies. Despite this variability, there were clear differences between large specimens of C. mutica and two species native to North America: C. alaskana and C. kennerlyi. The use of geometric morphometrics and the thin-plate spline method can serve to both complement descriptions using traditional keys and aid in identification of non-native species in novel geographical regions.
Forest structure and species distribution patterns were examined among eight topographically defined habitats for the 205 species with stems ≥ 1 cm dbh inhabiting a 25-ha plot in the Sinharaja rain forest, Sri Lanka. The habitats were steep spurs, less-steep spurs, steep gullies and less-steep gullies, all at either lower or upper elevations. Mean stem density was significantly greater on the upper spurs than in the lower, less-steep gullies. Stem density was also higher on spurs than in gullies within each elevation category and in each upper-elevation habitat than in its corresponding lower-elevation habitat. Basal area varied less among habitats, but followed similar trends to stem density. Species richness and Fisher's alpha were lower in the upper-elevation habitats than in the lower-elevation habitats. These differences appeared to be related to the abundances of the dominant species. Of the 125 species subjected to torus-translation tests, 99 species (abundant and less abundant and those in different strata) showed at least one positive or negative association to one or more of the habitats. Species associations were relatively more frequent with the lower-elevation gullies. These and the previous findings on seedling ecophysiology, morphology and anatomy of some of the habitat specialists suggest that edaphic and hydrological variation related to topography, accompanied by canopy disturbances of varying intensity, type and extent along the catenal landscape, plays a major role in habitat partitioning in this forest.
Temporal lobe and limbic structures may be abnormal in bipolar disorder. T2-weighted magnetic resonance imaging (MRI) scans frequently show deep white matter lesions. MRI was performed on 50 young (19–39 years) euthymic patients with bipolar disorder and 26 controls. Mean temporal lobe volumes were reduced in patients (right, 9.42 cm3; left, 6.33 cm3) but this could not be ascribed to a specific structure. Deep white matter lesions were present in 5 patients but no controls raising questions of their aetiological significance.
Exercise involving lengthening muscle actions, such as downhill running, results in delayed onset muscle soreness (DOMS), which may be attributable to reactive oxygen species (ROS). Although exercise causes oxidative stress, any link between ROS and DOMS remains speculative. There is emerging evidence to suggest that ROS play an important physiological role, assisting in the recovery process and protecting the cell from future damage; however, this has not been fully established. Despite this uncertainty as to the precise role of ROS, attempts to prevent post-exercise ROS production through antioxidant intervention are still common. The study investigated the effects of ascorbic acid supplementation on ROS production and DOMS following downhill running. Subjects were assigned to two groups. The ascorbic acid group (group AA) received 1 g ascorbic acid 2 h pre-, and for 14 d post-downhill running, whilst the placebo group (Pl group) received a placebo. Blood samples were drawn pre-supplement, pre- and post-exercise, and then 1, 2, 3, 4, 7 and 14 d post-exercise for analysis of ascorbate, malonaldehyde and total glutathione. DOMS was assessed using a visual analogue scale and pressure algometry. Muscle function was assessed using isokinetic dynamometry. Plasma ascorbate was elevated throughout in group AA compared with the Pl group. Downhill running resulted in DOMS in both groups. Muscle function was impaired post-exercise in both groups, although a delayed recovery was noted in group AA. Malonaldehyde increased 4 d post-exercise in the Pl group only. Ascorbic acid supplementation attenuates ROS production following downhill running, without affecting DOMS. Furthermore, ascorbic acid supplementation may inhibit the recovery of muscle function.