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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.
In this chapter I argue that the Great Recession has accelerated preexisting trends regarding transformations of employment opportunities and labor markets in industrial societies. These trends, in turn, are shaped through the dynamic and changing interplay of political and economic relationships in response to increasing globalization. However, national political and institutional structures are not powerless in the face of these changes. While they cannot insulate societies and young people from their effects, they can buffer, and to some extent shape, the ways in which these transformations impact on young people's experience of major economic and financial upheavals such as the Great Recession. More specifically I argue that one of the effects of the recession was to speed up preexisting trends regarding deskilling and casualization on young people's transition to work because of their vulnerability at the point of entry to the labor market. However, the differences in national political structures and institutional arrangements meant that young people in the UK, the USA, and Germany experienced the impact of the Great Recession in different ways. While national governments have not been able to reverse these trends they do have powerful instruments through which their impact on young people can be moderated.
The aim of this chapter is to assess the impact of globalization on youth transitions in times of social and economic change. The first section traces the interplay between economic and political relations at the global level that were responsible for the changes in the transition from school to work associated with the Great Recession. Specifically it documents the shift from nation-centric forms of production to global-centric forms of production. In doing this it highlights the common pressures and trends these global changes imposed on national economies. The second section illustrates how the national economies responded to these longer-term changes. It traces the link between these preexisting global trends and changes in the power balance between different national class and status groups and how globalization changed the occupational structures of the older industrial societies. The third section focuses on how these global processes of change were mediated at the national level by the political and institutional structures of the three societies, the USA, the UK, and Germany, and what their consequences were for young people.
In November 2013, national public health agencies in England and Scotland identified an increase in laboratory-confirmed Salmonella Mikawasima. The role of proton pump inhibitors (PPIs) as a risk factor for salmonellosis is unclear; we therefore captured information on PPI usage as part of our outbreak investigation. We conducted a case-control study, comparing each case with two controls. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were estimated using multivariable logistic regression. Thirty-nine of 61 eligible cases were included in the study. The median age of cases was 45 years; 56% were female. Of these, 33% were admitted to hospital and 31% reported taking PPIs. We identified an association between PPIs and non-typhoidal salmonellosis (aOR 8·8, 95% CI 2·0–38·3). There is increasing evidence supporting the existence of an association between salmonellosis and PPIs; however, biological studies are needed to understand the effect of PPIs in the pathogenesis of Salmonella. We recommend future outbreak studies investigate PPI usage to strengthen evidence on the relevance of PPIs in Salmonella infection. These findings should be used to support the development of guidelines for patients and prescribers on the risk of gastrointestinal infection and PPI usage.
We examine the relationship of biomass B and length L in the eastern oyster Crassostrea virginica by focusing on the scaling exponent b in the allometric equation B = aLb using four datasets: Delaware Bay, Chesapeake Bay, Galveston Bay and a regionally extensive compilation from the NOAA Mussel Watch Program. The average value of the scaling exponent in Delaware Bay and Chesapeake Bay is about 2. For Galveston Bay, the value is distinctly higher, near 2.6. Over all Mussel Watch sites, the value is again near 2. Within Delaware Bay, the salinity gradient exerts an important effect. Shells are longer for their meat weight at lower salinities. The range of scaling exponents revealed by Mussel Watch data is exceedingly large (b < 1 to >3). Scaling exponents below 2.5 are unusual in bivalves. Among bivalves, only other oyster taxa have comparably low scaling exponents averaging near 2. We propose that oyster biomass routinely scales nearer the square of the length rather than the cube and that this is a constraint imposed by the exigency of carbonate production for reef maintenance and accretion in the face of high rates of taphonomic degradation. The adaptation as a reef builder requires the formation of carbonate that rapidly breaks down, thus requiring that carbonate produced be maximized. A biomass-to-length scaling exponent of 2 provides a mechanism to maximize shell production relative to biomass, while at the same time providing maximum surface area for the all-important settling of oyster spat to maintain the population.
Ferromanganese nodules have been recognized widely as potentially important resources for strategic metals. However it remains unclear if the formation of these nodules is purely an abiotic process or if microorganisms are involved in their formation. To determine the microbial contributions, detailed organic geochemical analyses were performed on ferromanganese nodules collected from across the southwest Indian Ocean. These analyses reveal the presence of specific terrestrial, marine and petroleum derived biomarkers, consistent with formation in a marine setting with a substantial influx of terrestrially derived (higher plant detritus) and naturally occurring petroleum-related organic matter. In contrast, only trace amounts of general bacterial biomarkers, commonly present in these types of depositional environments, were present. This indicates that the formation of these ferromanganese nodules is predominantly an abiotic process although a minor contribution from microbial mediated processes to the growth of these nodules cannot be completely ruled out.
Choppers and chopping tools have long been associated with the Clactonian industries of Britain. They have either been dismissed as cores, or often described as woodworking tools, but have rarely been studied from a functional perspective. The purpose of this paper is to publish the results of a series of experiments which has been carried out to investigate the functional efficiency of choppers or chopping tools as compared to other alternative tools. These results are then reviewed in the light of the archaeological information from Clactonian and other Lower and Middle Pleistocene sites.
Due to the problems of definition, for the purposes of the experiments both chopping tools and choppers have been taken to be small nodules of pebbles which have had several flakes removed bifacially along at least one edge. The morphology of the working edge is identical to that found on the edges of many of the Clactonian cores. For this reason, chopping tools, choppers and cores are regarded as artefacts with potentially an identical function. In the experiments they are termed simply as chopping tools.
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.
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.
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.
Three MADS-box cDNA clones and two corresponding genomic sequences (gDNAs) have been isolated from the
bryophyte Physcomitrella patens and sequenced. Our findings indicate that the genes may be expressed in a tissue-
or age-specific manner, and that expression of one of them is regulated by an alternative splicing mechanism.
Conceptual translation of the clones reveals that the encoded MADS-domain proteins have the typical plant-domain pattern (MIKC). Additionally, there is a high degree of conservation of intron number and positions
between angiosperm MADS-box genes and the moss loci. These observations confirm the homology of moss and
higher plant MADS-box genes. We conclude that the MIKC pattern evolved in MADS-box genes after the
separation of the plant lineage from that of fungi and animals, and that it must have been present in the common
ancestor of mosses, ferns and seed plants. Therefore it evolved at least 400 million yr ago. Phylogenetic analysis
of a large subset of the sequenced plant MADS-box genes, incorporating those from P. patens, indicates that the
bryophyte genes are not orthologues of spermatophyte genes belonging to any of the well recognized higher plant
gene subfamilies. This conclusion accords well with reports that the known fern MADS-box genes also comprise
subfamilies distinct from those of higher plants. Therefore we tentatively propose that the gene duplication and
diversification events that created the MADS-box gene subfamilies, discernible in extant angiosperm and other
spermatophyte groups, occurred after separation of the moss and fern lineages from the lineage which produced
the higher plants.
Performance of seedlings of seven rain forest, canopy dominant Shorea species was studied in a transplant experiment in forest sites at three different elevations (low, mid and high) within the humid zone of southwest Sri Lanka. Five species generally inhabit low- to mid-elevations, one at mid- and lower montane elevations, and one exclusively at lower montane elevations. Temperature, rainfall and cloudiness varied with elevation. For each site seedlings were grown in pots under partial shade conditions using similar soils and evermoist conditions. All growth measures showed differences among elevation sites, among species and in the interaction between species and elevation sites. Performances of species collectively showed (i) decline in height and leaf number with increase in elevation, (ii) higher dry mass at low- and mid-elevation sites compared to that at high-elevation and (iii) a higher mass of single leaves at the mid-elevation site than at the high-elevation site. Rank order of species changed across elevations for both height and dry mass. Dry mass declined with elevation in four of the seven species studied. S. gardneri, the only exclusively lower montane species, increased dry mass with elevation. Height declined with elevation for six of the species with only S. gardneri showing no change. Changes with elevation in the rank order of species for total leaf number and mass of single leaves were small. However, total leaf number and masses of single leaves differed among species and among elevations. S. megistophylla and S. disticha had a few leaves with high individual masses, while S. gardneri, S. affinis and S. trapezifolia had many leaves with less mass per individual leaf. One group of species showed relatively little change in leaf number per seedling and large changes in mass of single leaves. The other group varied more in leaf number but mass of individual leaves remained constant. Growth allocation to leaf production versus individual leaf size appears related to the successional division of Shorea section Doona. Also all species grew better at the low-elevation site irrespective of their natural ranges except S. gardneri, whose natural range is restricted to high elevations, and exhibits markedly lower growth responsiveness than the other wide ranging species.
The present study was designed to investigate the interaction between body weight and energy expenditure in well-nourished individuals. Energy expenditure was determined during a 10 d highly controlled work programme in apparently well-nourished adult male construction workers with a wide range of body weights (mean weight: 63·9 (SD 11·0, range 46·7-80·1) kg, mean BMI: 22·5 (SD 3·8, range 16·7-28·9) kg/m2). Total energy expenditure (mean: 12·68 (SE 0·73) MJ/d or 1·78 (SE 0·07) x BMR) was determined using doubly-labelled water and the energy costs of work activities by Oxylog. The energy expenditure during work (mean: 5·75 (SE 0·29) MJ/day or 3·48 (SE 0·09) x BMR) was estimated from the energy costs of individual tasks and the time spent in those tasks. The energy expenditure during discretionary time (mean: 4·37 (SE 0·58) MJ/d or 1·49 (SE 0·17) x BMR) was calculated by subtracting occupation and sleep expenditure (taken as1 x BMR) from total expenditure. Food intake and discretionary time allocation were recorded by the subjects. The energy expenditure in the programmed work activities (expressed as a multiple of BMR) showed a significant increase (P=0·035) with increasing body weight, suggesting that the assumed constancy of BMR multiples across a wide range of body weights may not be valid. This assertion was supported by theoretical calculations based on empirically derived equations. In order to avoid errors which could be interpreted as metabolic ‘adaptation’ it may be necessary to take account of body weight when using the BMR-multiple approach to estimate energy requirements at low body weights.
Site data from 291 forest inventory plots in Mixed Dipterocarp Forest in central Sarawak were simplified by factor analysis. The distribution of the 33 commonest canopy tree species was related to site factor scores by ‘t’ tests. There appears to be a degree of edaphic influence on the distribution of many species. Fairly constant soil characteristics related to the lithology of the parent material appear to be more important than ephemerally variable pro perties such as organic matter or exchangeable cations. Magnesium appears to be particularly important, possibly because of an effect on the capacity of mycorrhizal root systems to absorb phosphorus.
On 7 Metageitnion of the Athenian year 322/1 B.C. a military engagement near Krannon, some 15 kilometres south-west of Larissa in Thessaly, marked the end of the so-called Lamian War in which a majority of the Greek mainland poleis, temporarily united under Athenian leadership, had attempted to terminate the Macedonian domination and to reassert their rights to individual autonomy. Although significant in that it heralded the final miscarriage of the Hellenic revolt, none the less the battle at Krannon was, in itself, a comparatively minor struggle in which the Greek forces, after an initial success, capitulated with surprising rapidity to the Macedonian commander-in-chief Antipater. That this war, in which the Hellenic armies had held the upper hand during the initial stages, should have concluded with such an insignificant clash of arms, is understandable only in the light of events at sea. The key battles which signalled the end of hopes for an overall Greek victory in their struggle for autonomy were naval ones—the most crucial being the naval confrontation determined near the island of Amorgos in the Sporades, some time prior to the battle of Krannon.
1. The transferrin types of 225 Jersey cows in thirteen herds, and 433 Australian Illawarra Shorthorn cows in twenty-four herds in Queensland were determined. The effect of transferrin type on lactation length, milk yield, butterfat yield and butterfat percentage was assessed by a leastsquares multiple linear regression analysis.
2. The results for the two breeds did not differ significantly. Combining the data from both breeds, it was found that on average D/D cows had lactations 13·9 days longer than A/A cows (P < 0·01), and yielded 449·7 lb. more mills (P < 0·01). The results for A/D cows were intermediate.
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