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Human pluripotent stem cell (hPSC)-derived progenies are immature versions of cells, presenting a potential limitation to the accurate modelling of disease associated with maturity or age. Hence, it is important to characterise how closely cells used in culture resemble their native counterparts. In order to select appropriate points in time for RPE cultures to reflect native counterparts, we characterised the transcriptomic profiles of hPSC-derived retinal pigment epithelium (RPE) cells from 1- and 12-month cultures. We differentiated the human embryonic stem cell line H9 into RPE cells, performed single cell RNA-sequencing of a total of 16,576 cells, and analysed the resulting data to assess the molecular changes of RPE cells across these two culture time points. Our results indicate the stability of the RPE transcriptomic signature, with no evidence of an epithelial – mesenchymal transition, and with maturing populations of RPE observed with time in culture. Assessment of gene ontology pathways revealed that as cultures age, RPE cells upregulate expression of genes involved in metal binding and antioxidant functions. This might reflect an increased ability to handle oxidative stress as cells mature. Comparison with native human RPE data confirmed a maturing transcriptional profile of RPE cells in culture. These results suggest that in vitro long-term culture of RPE cells allow the modelling of specific phenotypes observed in native mature tissue. Our work highlights the transcriptional landscape of hPSC-derived RPE as they age in culture, which provides a reference for native and patient-samples to be benchmarked against.

Motivated by the need to understand the compression of syntactic foam composites, we solve the canonical problem of buckling of a thin spherical shell embedded in a medium that is much softer than the shell. Syntactic foams comprise shells that usually have diameters in the micron range and are distributed inside a matrix medium that is typically polymeric. Such foams are commonly employed in a range of applications where high stiffness to density ratios are of interest. This can be tailored via choice of shell thickness and type, and filler volume fraction.Embedded glass microspheres fracture under sufficiently high loading, leading to a permanent softening of the syntactic foam. Embedded polymeric Expancel microspheres however are thought to buckle because the associated softening of the foam is recoverable. We determine critical buckling pressures in the practical scenarios of hydrostatic and uniaxial compressive loading states by solving a more general uniaxial loading problem. Critically, we investigate the thin-stiff shell limit, which yields very different results from a standard thin-shell limit under the assumption that the shell and matrix have stiffnesses of the same order. We employ nonlinear shell theory, linear stability analysis and rigorous asymptotics. We present numerical results for the critical buckling pressure over a wide range of shell thickness and contrasts in shell/matrix stiffnesses. Results for hydrostatic loading are compared against existing analytical and semi-analytical models for embedded shells. Under uniaxial loading we note that there are two distinct regions of parameter space, corresponding to equatorial and non-equatorial buckling regimes. The two non-dimensional parameters of critical importance are the shell thickness to radius ratio h/R and the shell to matrix shear modulus ratio µm/µs. By fixing one whilst varying the other we observe and describe the transition between these two regimes.

Christina M. Lill, who contributed to analysis of data, was inadvertently omitted from the author list in the originally published version of this article. This has now been corrected in both the PDF and HTML versions of the article. © 2019, The Author(s).

Supplemental minerals are routinely offered ad libitum to grazing cattle for the correction of major and trace mineral deficiencies of forages relative to the requirements of various classes of cattle and their expected performance. These mixes are often used as carriers for prophylactic feed additives, which normally have recommended intervals of consumption for them to be effective. However, adequate information is not available on the frequency that cattle visit free-choice mineral feeders. The objective of this study was to determine the frequency with which stocker steers grazing wheat pasture visit a feeder containing a free-choice mineral supplement. Steers were tracked during 53 d using radio-frequency identification ear tags and a custom built, computer monitored mineral feeder. Wheat pasture was grazed by 45 stocker steers (starting weight, 257 ± 4 kg). Individual steers visited the mineral supplement feeder 44.3% of the days monitored (24.5 to 69.8%). Daily weight gain averaged 1.03 ± kg/head. The correlation between frequency of mineral feeder visits with weight gain was 0.40 (P

Sepsis is broadly defined as the systemic inflammatory response to known or suspected infection. It remains a common cause of both morbidity and mortality in the critical care setting. Injury to multiple organ systems including the kidneys, liver, lungs, and brain is an important consequence of the overwhelming inflammatory response in sepsis. Current estimates indicate that acute kidney injury (AKI) occurs in approximately 60% of septic patients and significantly increases the risk of sepsis-associated mortality. Despite extensive laboratory and clinical study, therapy for sepsis and septic AKI remains limited to supportive measures. The purpose of this article is to review current understanding of the pathophysiology of AKI and sepsis and highlight areas where further work is needed. Important concepts, definitions, epidemiology, and experimental models of sepsis-induced AKI are introduced. The molecular mechanisms underlying sepsis-induced AKI are then extensively reviewed. Finally, we focus on the emerging role of mitochondrial dysfunction in septic AKI and discuss mitochondrial dynamics as a novel therapeutic target in this disease.

Nociceptive pathways with first-order neurons located in the trigeminal ganglion (TG) provide sensory innervation to the head, and are responsible for a number of common chronic pain conditions, including migraines, temporomandibular disorders and trigeminal neuralgias. Many of those conditions are associated with inflammation. Yet, the mechanisms of chronic inflammatory pain remain poorly understood. Our previous studies show that the neurotrophin brain-derived neurotrophic factor (BDNF) is expressed by adult rat TG neurons, and released from cultured newborn rat TG neurons by electrical stimulation and calcitonin gene-related peptide (CGRP), a well-established mediator of trigeminal inflammatory pain. These data suggest that BDNF plays a role in activity-dependent plasticity at first-order trigeminal synapses, including functional changes that take place in trigeminal nociceptive pathways during chronic inflammation. The present study was designed to determine the effects of peripheral inflammation, using tooth pulp inflammation as a model, on regulation of BDNF expression in TG neurons of juvenile rats and mice. Cavities were prepared in right-side maxillary first and second molars of 4-week-old animals, and left open to oral microflora. BDNF expression in right TG was compared with contralateral TG of the same animal, and with right TG of sham-operated controls, 7 and 28 days after cavity preparation. Our ELISA data indicate that exposing the tooth pulp for 28 days, with confirmed inflammation, leads to a significant upregulation of BDNF in the TG ipsilateral to the affected teeth. Double-immunohistochemistry with antibodies against BDNF combined with one of nociceptor markers, CGRP or transient receptor potential vanilloid type 1 (TRPV1), revealed that BDNF is significantly upregulated in TRPV1-immunoreactive (IR) neurons in both rats and mice, and CGRP-IR neurons in mice, but not rats. Overall, the inflammation-induced upregulation of BDNF is stronger in mice compared to rats. Thus, mouse TG provides a suitable model to study molecular mechanisms of inflammation-dependent regulation of BDNF expression in vivo.

The lives of poor landowners in tropical mountains depend upon their collective capacity to create and coordinate social preferences derived from their interacting communalistic, hierarchical, and reciprocal exchanges. External actors currently contend for these territories under market rules that are modifying such preferences. We present the design, experimental implementation, and analysis of results of a four-player, land-use board game with stark resource and livelihood limits and coordination/cooperation challenges, as played (separately) by 116 farmers and 108 academics, mainly in the tropical mountains of Chiapas, Mexico. In game session one, we trained and framed players in moral economy, a human core feeling and communalistic norm of solidarity and mutual obligation, which translates into "all players must survive." In session two, we explored to what extent moral economy resisted as a social preference under a hypothetical external monetary incentive scheme unfavorable to it. Using an approach that combines spot game analysis and experimental work, we studied the social preferences that emerged during session two among advantaged and disadvantaged players to deal with inequity in land appropriation and use when imminent "death" approaches. We make comparisons between farmers and academics. Players evolved moral economy, competitive domination, i.e., let competition decide, and coalition, i.e., advantaged players ask the dying to surrender land and die prematurely in exchange for a share of the dismal profits. Farmers basically stuck to the first two preferences in similar proportions whereas academics clearly shifted to coalition, a last-resort choice, which allowed disadvantaged players some final leverage and advantaged players use of liberated resources to improve efficiency. Coalition as strategic cooperation among the unequal is part of the culture in which academics are being educated as sustainability professionals and toward which farmers are being steered. In the stringent social-environmental conditions of this game, the results were a Pareto-superior form of equity, albeit with land surrendering, and many more deaths than other preferences.

In this paper, micron-scale frequency selective surfaces (FSS) are presented for the first time that exhibit multiple strong stopbands (>10dB) in the far-infrared (IR). Fractal and genetic algorithm (GA) synthesis techniques are employed in the design of single-layer, multiband IR FSS. These designs have been fabricated on thin, flexible polyimide substrates and characterized using Fourier transform infrared (FTIR) spectroscopy. Measurements show excellent agreement with predictions from a periodic method of moments (PMoM) analysis technique that takes into account metallic and dielectric losses. Additional design constraints were incorporated into the GA in order to guarantee that the synthesized FSS structures could be accurately fabricated.

A sensitivity analysis of the waterline method of constructing a Digital Elevation Model (DEM) of an intertidal zone using remote sensing and hydrodynamic modelling is described. Variation in vertical height accuracy as a function of beach slope is investigated using a set of nine ERS Synthetic Aperture Radar (SAR) images of the Humber/Wash area on the English east coast acquired between 1992 and 1994. Waterlines from these images are heighted using a hydrodynamic tide-surge model and interpolated using block kriging. On 1:500 slope beaches, an average block height estimation standard deviation of 18–22 cm is achieved. This rises to 27 cm on 1:100 slope beaches, and 32 cm on 1:30 slope beaches. The average heighting error at different slopes is decomposed into components due to waterline heighting error, inadequate sensor resolution and interpolation inaccuracy. It is shown that, at 1:500 slope, waterline heighting error and interpolation inaccuracy are the main error sources, whilst at 1:30 slope, errors due to inadequate sensor resolution become dominant. The ability of the technique to generate intertidal DEMs for almost the entire coastal zone in a complete ERS SAR scene covering 100×100 km is demonstrated.

Results are presented on a partial wave analysis of the Omega Eta final state produced in Pi- Proton interactions at 18 GeVc where Omega -> Pi+ Pi- Pi0, Pi0 -> 2 Gammas, and Eta -> 2 Gammas. We observe the previously unreported decay mode Omega(1650) -> Omega Eta and a new 1(+-) meson state h1(1595) with a mass M=1594(15)(+10)(-60) MeV/c^2 and a width Gamma=384(60)(+70)(-100) MeV/c^2. The h1(1595) state exhibits resonant-like phase motion relative to the Omega(1650).

An illustration of how sediment transport may be measured over a large dynamic intertidal area at reasonable cost and spatiotemporal resolution using the waterline method employing remote sensing and hydrodynamic modelling is presented. Areas and volumes of accretion and erosion were measured in the study area of Morecambe Bay in north-west England over the period 1992–97. Tidal asymmetry is considered to be the dominant agent of sediment movement in the bay, with waves being of secondary importance. Waterlines (i.e. land-sea boundaries) were extracted from 31 synthetic aperture radar images of the bay covering a substantial fraction of the tidal range. Heights were attached to the waterlines using water elevations from nested hydrodynamic tide-surge models. Interpolation in space and time was carried out to produce a continuous spatiotemporal height map of the intertidal zone. Height maps with a spatial resolution of about 50 m and height accuracy of about 40 cm were constructed over an area of about 350 km 2 . Strong temporal decorrelation in the bay limited the height accuracy achievable. Differences between height maps for 1992–94 and 1995–97 allowed sediment volume changes to be extracted. The intertidal region showed a loss of 16·1±4·5×10 6 m 3 over the period, almost all the change being due to a significant decrease between mean sea level and the low water mark. Changes were also measured in three of the main river estuaries within the bay, the Leven, Kent and Lune. These included movement of the Leven north-east by about 2 km cutting into Cartmel Wharf, accretion seaward of Grange-over-Sands and changes in the low water channels at the mouth of the Lune. These changes could be used to validate sediment transport models of the bay.

New results from experiments on the infrared photodissociation of 36Ar40Ar+ are compared with previous measurements on 40Ar+ 2. A distinct difference in behaviour between the two ions, provides clear evidence that, following electron impact ionization/excitation, large argon clusters eject dimers either as neutrals or ions in vibrational and electronic excited states.

A 33 kDa peroxidase was purified from intercellular wash fluids of cucumber leaves expressing systemic acquired resistance. Partial amino acid sequence data of the peroxidase were used to obtain a full length 1218 base pair (bp) cDNA clone (pCS1) which encoded the peroxidase. Deduced amino acid sequences from pCS1 matched observed amino acid sequences of the purified protein and also indicated that pCS1 was typical of known plant peroxidases. Three other cDNAs (pCS2, pCS3 and pCS4) were also isolated and found to be closely related to pCS1. RNA gel blots, using a 153 bp fragment of pCS1 as a probe, demonstrated accumulation of peroxidase mRNA in the second leaf of cucumber seedlings at 18 h after inoculation of the first leaf with the hypersensitive response-inducing bacterium Pseudomonas syringae pv. syringae . Detaching the inoculated leaf at intervals after inoculation demonstrated that this leaf only needed to be on the plant for 4 h to result in systemic induction of the peroxidase mRNA. This indicated that the systemic signal that leads to the expression of peroxidase was mobilized out of the inoculated leaf by 4 h. Exogenous application of salicylic acid, a putative endogenous signal for resistance, also induced accumulation of peroxidase mRNA.

An antisense phosphorothioate oligonucleotide complementary to the intron-exon boundary of human cytomegalovirus genes UL36 and UL37 (UL36ANTI) reduced the yield of infectious virus by 99% and inhibited human cytomegalovirus DNA replication at a concentration of 0.08 microM. In addition, oligonucleotides with base substitutions which resulted in base pair mismatches showed lesser degrees of activity, indicating a sequence-specific antisense mechanism. UL36ANTI was also shown to inhibit DNA replication of ganciclovir-resistant strains and human cytomegalovirus clinical isolates.

This study further examines the involvement of protein kinase C and superoxide anions in the inhibition of agonist-induced endothelium-dependent relaxation by oxidised low density lipoprotein (LDL). Pretreatment of rabbit aorta rings with either oxidised low density lipoprotein or phorbol dibutyrate (PDB) inhibited acetylcholine-induced endothelium-dependent relaxation, but not endothelium-independent relaxations to glyceryl trinitrate. Prior exposure of the rings to either of the specific protein kinase C inhibitors Ro 31-8220 or Ro 31-7549 prevented or reduced respectively the inhibition of acetylcholine-induced relaxation by oxidised LDL or PDB. Neither inhibitor alone affected acetylcholine-induced relaxation. We directly demonstrate for the first time that oxidised, but not native, LDL produces a prolonged activation of protein kinase C in endothelial cells, which was prevented by pretreatment with Ro 31-8220. Oxidised or native LDL, or Ro 31-8220 increased superoxide anion production by rabbit aorta...

For a planter using a single seed metering mechanism, the ability to place seeds a given distance apart in a row is an important factor in evaluating a planter’s performance. Data collected to measure a planter’s accuracy often consist of a series of distances between plants. The distance between plants within a row is influenced by a number of factors including multiple seeds dropped at the same time, failure of a seed to be dropped, failure of a seed to emerge, and variability around the drop point. The objective of this article is to compare alternative measures of accuracy in seed placement for planters using single seed metering mechanisms. The measures compared are the mean, standard deviation, quality of feed index, multiples index, miss index, and precision. Of the measures considered, both the mean and standard deviation were judged to be inappropriate measures of accuracy.

The behaviour of 24 primiparous sows around parturition was examined from continuous video-records to investigate the effects of accommodation type (farrowing crate vs pen) and substrate (straw vs no straw), in a factorial experiment, on sow behaviours that may influence piglet survival. The experiment was part of a larger experiment involving 64 sows and litters, which examined the effects of the farrowing/lactation environment on sow behaviour, and piglet survival and growth to weaning. During the 24 h pre-partum, sows spent less time side lying (29.3 vs 42.3% of observations; P P P The occurrence of pawing at the bare floor was greater in crates than in pens (0.6 vs 0.3% of observations; P P P P P P The data suggest that factors in the environment of the peri-parturient sow affect the quantity of pre-partum nesting-like behaviour, such as root/nose/paw behaviours and manipulation of straw. However, the fact that environments that elicited more maternal behaviour did not promote piglet survival, suggested that piglet survival may be more affected by the structural/thermal environment than by the sow's behaviour.

When analysing the performance of a system, we are often interested in long-run properties, such as the proportion of time it spends in a certain state. Stochastic process algebras help us to answer this sort of question by building a compositional model of the system, and using tools to analyse its underlying Markov chain. However, compositionality in the model leads to a state space explosion in the Markov chain, which severely limits the size of models we can analyse. Because of this, we look for abstraction techniques that allow us to analyse a smaller model that safely bounds the properties of the original. In this paper, we present an approach to bounding long-run properties of models in the stochastic process algebra PEPA. We use a method called stochastic bounds to build upper and lower bounds of the underlying Markov chain that are lump able, and therefore can be reduced in size. Importantly, we do this compositionally, so that we bound each component of the model separately, and compose these to obtain a bound for the entire model. We present an algorithm for this, based on extending the algorithm by Fourneau et al to deal with partially-ordered state spaces. Finally, we present some results from our implementation, which forms part of the PEPA plug-in for Eclipse. We compare the precision and state space reduction with results obtained by computing long-run averages on a CTMDP-based abstraction.

When analysing the performance of a complex system, we typically build abstract models that are small enough to analyse, but still capture the relevant details of the system. But it is difficult to know whether the model accurately describes the real system, or if its behaviour is due to modelling artifacts that were inadvertently introduced. In this paper, we propose a novel methodology to reason about modelling artifacts, given a detailed model and a high-level (more abstract) model of the same system. By a series of automated abstraction steps, we lift the detailed model to the same state space as the high-level model, so that they can be directly compared. There are two key ideas in our approach -- a temporal abstraction, where we only look at the state of the system at certain observable points in time, and a spatial abstraction, where we project onto a smaller state space that summarises the possible configurations of the system (for example, by counting the number of components in a certain state). We motivate our methodology with a case study of the LMAC protocol for wireless sensor networks. In particular, we investigate the accuracy of a recently proposed high-level model of LMAC, and identify some modelling artifacts in the model. Since we can apply our abstractions on-the-fly, while exploring the state space of the detailed model, we can analyse larger networks than are possible with existing techniques.

Oxidation of low density lipoprotein (LDL) in atherosclerotic lesions may be involved in converting macrophages into cholesterol-laden foam cells, a major characteristic of atherosclerotic lesions. It has been reported, and is widely believed, that endothelial cells derived from rabbit, pig and human aortas, but not those derived from bovine aortas, are capable of oxidising LDL in vitro. We have re-investigated this subject and found that during a 48-h incubation period bovine aortic endothelial cells (both in primary culture and in subcultures) were capable of consistently modifying LDL, increasing its uptake and degradation by macrophages by more than 4-fold. Incubation of LDL with bovine aortic endothelial cells for only 24 h, however, produced inconsistent modification of the LDL, whereas mouse peritoneal macrophages consistently modified LDL in 24 h. The modification of LDL by bovine aortic endothelial cells was an oxidative process, as the chain-breaking antioxidants, alpha-tocopherol and probucol, completely or greatly inhibited it. Thus, bovine aortic endothelial cells are capable of oxidising LDL but they are slower at doing so than are certain other types of cells. Nitric oxide generated by activated macrophages has very recently been shown to inhibit their oxidation of LDL. We have therefore investigated whether or not the inhibition of the constitutive nitric oxide synthase of bovine or porcine aortic endothelial cells would increase their rate of oxidation of LDL.(ABSTRACT TRUNCATED AT 250 WORDS)

Objective:To report the contamination of ventilator equipment with Bacillus cereus and to outline the measures taken to trace the source of the organism.Design:A prospective survey of all intensive care unit patients who were culture-positive for B cereus and obtaining of environmental cultures of the cleaning and assembly area of the respiratory services division between October 1991 and September 1992.Setting And Patients:Ventilated patients from a 16-bed medical and surgical intensive care unit (ICU) in a 1,000-bed adult tertiary care hospital.Interventions And Results:From October 1991 to April 1992, B cereus colonized the ventilator circuitry of patients in the ICU. One of two washer/decontaminators in the cleaning and assembly area of the respiratory services division was found to yield the microorganism consistently from the water intake port. The design of the machine precluded easy decontamination of the port with 2% gluteraldehyde and a second outbreak occurred. Following the second outbreak, aqueous chlorhexidine in a final concentration of 0.05% was added to the first of two pasteurization cycles in an attempt to achieve sporicidal activity. This ended the outbreak. Sixty-two patients became colonized with the organism including two with nonfatal Bacillus sepsis and one death due to pneumonia associated with the organism.Conclusion:This experience emphasizes the importance of obtaining cultures of machine parts to identify the source of contamination and thereby direct control measures. Use of chlor-hexidine gluconate at high temperatures effectively eradicated B cereus from ventilator circuitry in a practical and cost-effective manner.

1. We have investigated whether porcine endocardial cells in culture express the inducible, Ca(2+)-independent form of nitric oxide (NO) synthase. 2. NO synthase activity in cytosolic extracts of endocardial cells was measured by estimation of the rate of formation of L-[14C]-citrulline from L-[14C]-arginine. 3. Treatment of the cells in culture with lipopolysaccharide or cytokines induced a Ca(2+)-independent NO synthase activity in the cell cytosol. The combination of tumour necrosis factor (TNF alpha, 10 ng ml-1) and interleukin-1 beta (IL-1 beta, 10 ng ml-1) induced the greatest enzyme activity. 4. The increased Ca(2+)-independent NO synthase activity following exposure to cytokines was paralleled by an increase in guanosine 3':5'-cyclic monophosphate (cyclic GMP) levels in the endocardial cell cytosol. 5. Simultaneous addition of dexamethasone (0.01-1 microM) or cycloheximide (0.03-3 microM) inhibited in a concentration-dependent manner TNF alpha- and IL-1 beta-induced expression of Ca(2+)-independent NO synthase activity. Neither dexamethasone (1 microM) nor cycloheximide (3 microM) had any effect on the activity of the constitutive NO synthase. 6. The possible pathophysiological consequences of endocardial expression of the inducible NO synthase are discussed.

The stochastic process algebra PEPA is widely used for performance modelling, and a large part of its success is due to its rich tool support. As a compositional Markovian formalism, however, it suffers from the state space explosion problem, where even small models can lead to very large Markov chains. One way of analysing such models is to use abstraction - constructing a smaller model that bounds the properties of the original. We present an extension to the PEPA plug-in for Eclipse that enables abstracting and model checking of PEPA models. This implements two new features. The abstraction view provides a graphical interface for labelling and aggregating states of individual PEPA components. The model checking view provides an interface for constructing CSL properties, which are then verified with respect to the specified abstraction. We have an internal CSL model checker for CTMDPs, so the tool can be used as a stand-alone.

The behaviour of 64 primiparous sows and the survival and growth of their piglets to weaning were recorded in an experiment with 16 replicates to investigate the effects of accommodation type (crate vs. pen) and substrate (straw absent or present) around farrowing and during lactation. Litters of sows that farrowed without straw had more (P < 0.01) live-born piglets than sows with straw (9.4 vs. 9.1 piglets), while litters in crates tended to have lower (P < 0.06) pre-weaning mortality levels than litters in pens (10.5% vs. 16.5% of liveborn). A high proportion of piglet deaths was because of savaging by the sow and overlying (4.1% and 3.1% of live-born, respectively), and the occurrence of overlying was higher in the pen than crate treatments. Mean piglet liveweight at weaning and weight gain from birth to weaning were less in the no-straw than straw-added treatments because of a strong (P < 0.001) factor interaction: litters of sows in the pen/straw-added treatment were heavier at weaning and grew faster from birth to weaning than litters in the other treatments. There were no differences in the levels of total activity of sows during lactation, but there were effects of factors and treatments on some classes of behaviour. On Day 1 of lactation, the presence of straw increased (P < 0.01) the duration of rapid suckling grunts. In the first week of lactation, there was a significant interaction effect on time spent side-lying and belly-lying: sows in the crate/no-straw treatment spent less (P < 0.05) time side-lying and more (P < 0.05) time belly-lying than sows in most of the other treatments. Also, sows in the straw-added treatments tended (P < 0.07) to perform more piglet-oriented vocalisations and investigation than sows in the no-straw treatments. It is concluded that the increased performance of maternal behaviour by sows does not appear to contribute to piglet survival, especially in the intensive farrowing crate environment.

The behaviour of 18 primiparous Large White (LW) or LW × Duroc sows and their litters was observed during 6 days in lactation (1, 2, 3, 7, 14 and 21) in two housing treatments: (1) farrowing crate (1.6 m × 2.2 m) without straw: (2) farrowing pen (2.8 m × 2.8 m) with straw added. After farrowing, litter size was standardized to nine or ten piglets. Sows in crates spent less (P < 0.01) time performing rapid suckling grunts between 09:00 and 13:00 h on observation days, and had shorter (P < 0.001) bouts of this behaviour than sows in pens with straw. Litters in the crate treatment spent less (P < 0.03) time performing rapid sucking movements (drinking) and displayed shorter (P < 0.01) bouts of drinking than litters in pens with straw. Piglet location within the pen/crate was affected by treatment: litters in crates, particularly on the first day of lactation, spent more time (P < 0.01) in the heated creep area and less (P < 0.01) time in the open away from the creep area, and away from the close proximity of the sow, than litters in the pen treatment. The observed increase in rapid sucking movements (drinking) by litters in the pen treatment did not result in an increased weight gain by piglets. It was concluded that the (apparent) increase in milk intake was not partitioned to growth, but may have been used by piglets to maintain body temperature with the increased time piglets spent away from the creep and the sow in the pen treatment.

t is now recognised that vascular endothelium plays Im any functional roles including that of modulating vascular smooth muscle tone through the release of vasoactive agents such as endothelium derived relaxing factor (EDRF).’-’ The heart phylogenetically is a specialised development of the vascular system. Its intracavitary lining of endocardial endothelium might therefore be expected to have properties in common with those of endothelium lining the rest of the vascular tree. Agents produced by endothelium might also influence contraction of underlying cardiac muscle as they do in vascular smooth muscle. This has indeed now been shown to be the case

The loss of duodenal folds visible endoscopically has recently been reported as being a marker for celiac disease. We have investigated the sensitivity and specificity of this finding with a prospective study in 75 patients with symptoms or results of investigations compatible with celiac disease. Reported duodenal fold appearance was compared with histological findings, disaccharidase levels, and clinical diagnosis. Fifteen patients were found to have celiac disease and 11 had reduced or absent duodenal folds compared with only 2 of 60 patients who did not have celiac disease (p

A novel unidentified agent, provisionally named 'endocardin', has been shown to be released from endocardial endothelium. Endocardin has a unique prolonging effect on myocardial contraction. In contrast, endothelium-derived relaxing factor released from endocardial endothelium has the opposite effect of abbreviating contraction. Jerry Smith and colleagues discuss the mechanisms of action of these agents and their possible physiology and pathophysiology.

Redistribution of Zr in metallic nuclear fuels is potentially important to fuel performance. However, it is difficult to determine why Zr redistributes because the reactor environment provides several driving forces. This environment cannot be reproduced outside the reactor, but reactor testing is time-consuming and expensive. Therefore, in-reactor experiments must be as definitive as possible. Computer simulation can guide reactor testing in two ways. Firstly, simpler situations, with fewer variables, can be modeled mathematically, and the predictions compared to in-reactor results to assess importance of modeled variables. The second way in which computer simulation can be useful is by helping researchers assess differences between in-reactor results and corresponding out-of-reactor experiments. Methods presented in this paper can help researchers to interpret such differences. This paper also addresses the more general question of whether TGSs are reliable indicators of in-reactor thermotransport. To do so, this study makes conservative estimates of potential differences between compositional profiles in TGSs and fuel elements. If these overestimated differences are not large enough to make TGSs misrepresent in-reactor thermotransport effects, it will be concluded that TGSs are reliable indicators. This paper ignores irradiation effects and assumes conservation of lattice sites. Consistent with the desire to produce conservative estimates,more » materials properties and other parameters used in this work overestimate differences between fuel elements and TGSs unless stated otherwise.« less

Plasma free cortisol concentrations were measured in 24 primiparous sows housed from Day 104 after mating up to Day 2 after parturition. Concentrations were measured in 22 of these sows, from Days 2–29 of lactation, housed in either commercial farrowing crates (Crate treatment) or farrowing pens with straw added (Pen treatment). The mortality and growth data of litters from the time of birth to weaning were also recorded. The mean plasma free cortisol concentration was higher in sows housed in the Crate treatment, compared with sows housed in the Pen treatment, on the first day of treatment (8.2 and 5.8 nmol l−1, respectively, P The data suggest that housing treatment around parturition and during lactation may have only limited effects on the welfare of sows, providing that lactation is no longer than 28 days. On Days 21 and 24, there were no effects of treatment on free cortisol concentrations and no response to the exogenous adrenocorticotrophic hormone (ACTH), respectively. However, on Day 28, there were mean increases in the concentrations of free cortisol of approximately 150% and approximately 60%, respectively; these may have been the result of unavoidable attention of the piglets to the sows.

Redistribution of Zr in metallic nuclear fuels is potentially important to fuel performance. Unfortunately, Zr redistribution is difficult to understand because the irradiation environment provides several driving forces that could induce it. Among these driving forces are fluxes of point defects, diffusion of fission products, and high thermal gradients. This environment is difficult to reproduce outside of the reactor; however, reactor testing is time-consuming and expensive. Therefore, in-reactor experiments must be as definitive as possible. Computer simulation can serve as a guide to reactor testing in such circumstances. Simpler situations, with fewer variables, can be modeled mathematically, and the predictions compared to in-reactor results to assess the importance of the modeled variables. This paper investigates the ability of thermotransport to cause extensive redistribution. An interesting aspect of this approach is that because Zr is non-fissile, its migration changes the temperature profile. Hence, at steady state, the Zr distribution must satisfy the thermotransport equation while producing a temperature profile that allows it to do so. Because the purpose of this study is to investigate general features of compositional profiles produced by thermotransport, a binary alloy was modeled. This study ignores radiation-induced vacancy effects and assumes conservation of lattice sites.

1. Endocardial cells release factors which regulate myocardial contractility and guanosine 3':5'-cyclic monophosphate (cyclic GMP) levels. One of these factors is indistinguishable from endothelium-derived relaxing factor (EDRF). 2. The effluent from pig heart endocardial cells cultured on microcarrier beads caused the relaxation of a pig coronary artery ring denuded of endothelium. This relaxation was enhanced by a combination of superoxide dismutase and catalase and was attenuated by haemoglobin, which binds nitric oxide (NO), and by inhibitors of NO synthase, NG-monomethyl-L-arginine (L-NMMA) or NG-nitro-L-arginine. 3. A Ca(2+)-, L-arginine- and NADPH-dependent enzyme activity which generated NO was detected by a specific spectrophotometric assay in cytosol prepared from endocardial cells. The formation of NO was inhibited in a concentration-dependent manner by L-NMMA (but not D-NMMA) and this could be partially reversed upon addition of excess L-arginine. 4. Like endothelial cells from the blood vessels, the endocardial cells possess the ability to synthesize NO, which may act to regulate myocardial contractility.