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Polyunsaturated fatty acids (PUFAs) are important components of the diet of mammals. Their role was first established when the essential fatty acids (EFAs) linoleic acid and α-linolenic acid were discovered nearly a century ago. However, most of the biochemical and physiological actions of PUFAs rely on their conversion to 20C or 22C acids and subsequent metabolism to lipid mediators. As a generalisation, lipid mediators formed from n-6 PUFAs are pro-inflammatory while those from n-3 PUFAs are anti-inflammatory or neutral. Apart from the actions of the classic eicosanoids or docosanoids, many newly discovered compounds are described as Specialised Pro-resolving Mediators (SPMs) which have been proposed to have a role in resolving inflammatory conditions such as infections and preventing them from becoming chronic. In addition, a large group of molecules, termed isoprostanes, can be generated by free radical reactions and these too have powerful properties towards inflammation. The ultimate source of n-3 and n-6 PUFAs are photosynthetic organisms which contain Δ-12 and Δ-15 desaturases, which are almost exclusively absent from animals. Moreover, the EFAs consumed from plant food are in competition with each other for conversion to lipid mediators. Thus, the relative amounts of n-3 and n-6 PUFAs in the diet are important. Furthermore, the conversion of the EFAs to 20C and 22C PUFAs in mammals is rather poor. Thus, there has been much interest recently in the use of algae, many of which make substantial quantities of long-chain PUFAs or in manipulating oil crops to make such acids. This is especially important because fish oils, which are their main source in human diets, are becoming limited. In this review, the metabolic conversion of PUFAs into different lipid mediators is described. Then, the biological roles and molecular mechanisms of such mediators in inflammatory diseases are outlined. Finally, natural sources of PUFAs (including 20 or 22 carbon compounds) are detailed, as well as recent efforts to increase their production. [ABSTRACT FROM AUTHOR]

The ability to reversibly modulate peptide secondary structures, such as the β‐turn, allows for precise control of biological function, including protein interactions. Herein, we describe the design of two scaffolds containing an azobenzene moiety with flanking alanine or β‐alanine residues to probe essential features for photo‐control of a β‐turn within a cyclic peptide. To efficiently cyclize the designed linear peptides, prior isomerization of the azobenzene‐containing amino acid from the trans to the cis form was necessary. The two cyclic peptides (TAp and TApβ) were found to undergo rapid photochemical conversion to the cis isomer of the azobenzene, with a more gradual thermal reversion to the trans isomer over the course of a week at 37 °C. Spectroscopic analysis and restrained molecular dynamics simulation of the cis form of TAp and TApβ revealed type II and type II' β‐turns within the cyclic peptides, respectively. The trans isomer of the TAp cyclic peptide was found to have a kink within the peptide structure, whereas the longer trans‐TApβ contained a more extended conformation. TApβ, therefore, demonstrates a clearer difference in the cyclic peptide conformations when in the cis versus trans form, a feature that may prove beneficial for use with biologically active β‐turn sequences. [ABSTRACT FROM AUTHOR]

Nonlethal disturbance of animals can cause behavioral and physiological changes that affect individual health status and vital rates, with potential consequences at the population level. Predicting these population effects remains a major challenge in ecology and conservation. Monitoring fitness-related traits may improve detection of upcoming population changes, but the extent to which individual traits are reliable indicators of disturbance exposure is not well understood, especially for populations regulated by density dependence. Here we study how density dependence affects a population's response to disturbance and modifies the disturbance effects on individual health and vital rates. We extend an energy budget model for a medium-sized cetacean (the long-finned pilot whale Globicephala melas) to an individual-based population model in which whales feed on a self-replenishing prey base and disturbance leads to cessation of feeding. In this coupled predator-prey system, the whale population is regulated through prey depletion and the onset of yearly repeating disturbances on the whale population at carrying capacity decreased population density and increased prey availability due to reduced top-down control. In populations faced with multiple days of continuous disturbance each year, female whales that were lactating their first calf experienced increased mortality due to depletion of energy stores. However, increased prey availability led to compensatory effects and resulted in a subsequent improvement of mean female body condition, mean age at first reproduction and higher age-specific reproductive output. These results indicate that prey-mediated density dependence can mask negative effects of disturbance on fitness-related traits and vital rates, a result with implications for the monitoring and management of marine mammal populations. [ABSTRACT FROM AUTHOR]

The article offers information on the use of wires, metal from the early times. Topics discussed include illustration of wire milling tools from Abraham Rees; woodcut engraving illustrating mining rail trucks; and artistic forged metals from Florence, Italy. It also mention that metal played as the material basis for the period's architectural and utopian fantasies. It also mention about the works of artist Sigfried Giedion.

Lipids are key molecules for membranes, energy storage and signalling. I have been privileged to have worked in such a diverse field and in organisms from microbes to humans. Here I will describe some of those contrasting areas which range from environmental impacts to food production and on to human health. It has been a fascinating journey which still continues to excite me. [ABSTRACT FROM AUTHOR]

t 1 noise appears as random or semi-random spurious streaks along the indirect t 1 ( F 1) dimension of a 2D or nD NMR spectrum. It can significantly downgrade spectral quality, especially for spectra with strong diagonal signals such as NOESY, because useful and weak cross-peaks can be easily buried under t 1 noise. One of the significant contributing factors to t 1 noise is unwanted and semi-random F 2 signal modulation during t 1 acquisition. As such, t 1 noise from different acquisitions is unlikely to correlate with each other strongly. In the case of NOESY, co-addition of multiple spectra significantly reduces t 1 noise compared with conventional acquisition with the same amount of total acquisition time and resolution. [ABSTRACT FROM AUTHOR]

Acyl-CoA:diacylglycerol acyltransferase (DGAT, EC 2.3.1.20) catalyzes the last reaction in the acyl-CoA-dependent biosynthesis of triacylglycerol (TAG). DGAT activity resides mainly in DGAT1 and DGAT2 in eukaryotes and bifunctional wax ester synthase-diacylglycerol acyltransferase (WSD) in bacteria, which are all membrane-bound proteins but exhibit no sequence homology to each other. Recent studies also identified other DGAT enzymes such as the soluble DGAT3 and diacylglycerol acetyltransferase (EaDAcT), as well as enzymes with DGAT activities including defective in cuticular ridges (DCR) and steryl and phytyl ester synthases (PESs). This review comprehensively discusses research advances on DGATs in prokaryotes and eukaryotes with a focus on their biochemical properties, physiological roles, and biotechnological and therapeutic applications. The review begins with a discussion of DGAT assay methods, followed by a systematic discussion of TAG biosynthesis and the properties and physiological role of DGATs. Thereafter, the review discusses the three-dimensional structure and insights into mechanism of action of human DGAT1, and the modeled DGAT1 from Brassica napus. The review then examines metabolic engineering strategies involving manipulation of DGAT, followed by a discussion of its therapeutic applications. DGAT in relation to improvement of traits of farmed animals is also discussed along with DGATs in various other eukaryotic organisms. [ABSTRACT FROM AUTHOR]

Human activities that impact wildlife do not necessarily remove individuals from populations. They may also change individual behaviour in ways that have sublethal effects. This has driven interest in developing analytical tools that predict the population consequences of short-term behavioural responses. In this study, we incorporate empirical information on the ecology of a population of bottlenose dolphins into an individual-based model that predicts how individuals' behavioural dynamics arise from their underlying motivational states, as well as their interaction with boat traffic and dredging activities. We simulate the potential effects of proposed coastal developments on this population and predict that the operational phase may affect animals' motivational states. For such results to be relevant for management, the effects on individuals' vital rates also need to be quantified. We investigate whether the relationship between an individual's exposure and the survival of its calves can be directly estimated using a Bayesian multi-stage model for calf survival. The results suggest that any effect on calf survival is probably small and that a significant relationship could only be detected in large, closely studied populations. Our work can be used to guide management decisions, accelerate the consenting process for coastal and offshore developments and design targeted monitoring. [ABSTRACT FROM AUTHOR]

The article looks at a 1957 memoradum written by art and architecture critic Edgar Kaufmann, Jr. to industrial designer Eliot Noyes and a 1964 memorandum written by ergonomist Serge Boutourline, Jr. to Robert S. Lee, director of research at International Business Machines Corp. (IBM), both regarding the design of computer interfaces. According to the author, these documents illustrate important moments in the history of computer design. Details on the spatial separation of computer operators from certain computer components and on the rhetorical and political aspects of computing are presented.

The article focuses on contribution of theologian Sallie McFague in theology in reference to works done by her. Topics discussed include how faith communities are related with spiritual and religious convictions, perception of Anglicans regarding life and their comparison with modern American thinking and environmental sustainability and human survival. it also mentions some of her writings which include "Literature and the Christian Life", "Speaking in Parables" and "Metaphorical Theology."

As an undergraduate student of Medical Biochemistry, I was unsure what I wanted to do with my life after graduating. Then, one day, I had a lecture about membrane lipids. It turned out that not only were they far from the inert structural compounds that they were often portrayed to be but they turned over quite rapidly. But there was one class of lipids-the higher inositides (PtdIns4P, PtdIns (4, 5) P2)-that had a T½ of only a few minutes! I found this fascinating and was inspired not only to do my post-graduate work with J. N. (Tim) Hawthorne on inositides but to continue work on lipids ever since. I have no regrets for it has been a fascinating journey. The great French scientist Chevreul made contributions to several different areas of science so, in humble appreciation of his seminal discoveries, I will discuss some diverse lipid topics that I have worked on. [ABSTRACT FROM AUTHOR]

Highlights: [•] Molecular markers to determine sources of organic matter in waters is reviewed. [•] Human and animal wastes are distinguishable by fecal sterols and bile acids. [•] Artificial sweeteners identify input of human wastewater. [•] LC–MS should facilitate analysis of molecular markers in environmental studies. [ABSTRACT FROM AUTHOR]

An essay is presented that explores the relationship between architecture in 20th century England and the concept of the risk society. Topics discussed include the efforts of British engineer Ove N. Arup to use architecture to protect English cities from aerial bombing, the importance of the architectural theory of space to these efforts, and the impact of warfare on architecture.

Plant oils are a very valuable agricultural commodity. They are currently mainly used (>80%) for food and animal feed but, increasingly, they have utility as renewable sources of industrial feedstocks or biofuel. Because of finite agricultural land, the best way to increase availability (in order to match demand) is by improving productivity. To do this requires a knowledge of metabolism and its regulation. Various methods have been used to provide information but only systems biology can yield quantitative data about complete metabolic pathways. We have used metabolic control analysis to provide information about major oil crops such as oilseed rape, oil palm, olive, and soybean. Such knowledge has then been used to inform genetic manipulation for crop improvement. [ABSTRACT FROM AUTHOR]

Increasing the seed oil content of Brassica species and other major oilseed crops is of paramount importance in maintaining a future supply of vegetable oil for a growing global population. Currently, commercially-available Brassica species with enhanced seed oil content have all been developed through plant breeding. Many quantitative trait loci including gene interactions are involved in the control of seed oil content. Despite this complexity, manipulation of specific steps in storage lipid biosynthesis using genetic engineering has resulted in transgenic lines of Brassica napus with increased seed oil content. Recent studies suggest that engineering of seed oil content can be guided using methods in metabolic analysis. [ABSTRACT FROM AUTHOR]

Behavioural change in response to anthropogenic activities is often assumed to indicate a biologically significant effect on a population of concern. Disturbances can affect individual health through lost foraging time or other behaviours, which will impact vital rates and thus the population dynamics. However, individuals may be able to compensate for the observed shifts in behaviour, leaving their health and thus their vital rates and population dynamics, unchanged., We developed a mathematical model simulating the complex social, spatial, behavioural and motivational interactions of coastal bottlenose dolphins ( Tursiops truncatus) in the Moray Firth, Scotland, to assess the biological significance of increased rate of behavioural disruptions caused by vessel traffic., We explored a scenario in which vessel traffic increased from 70 to 470 vessels a year in response to the construction of a proposed offshore renewables' facility. Despite the more than sixfold increase in vessel traffic, the dolphins' behavioural time budget, spatial distribution, motivations and social structure remain unchanged., We found that the dolphins are able to compensate for their immediate behavioural response to disturbances by commercial vessels. If the increased commercial vessel traffic is the only escalation in anthropogenic activity, then the dolphins' response to disturbance is not biologically significant, because the dolphins' health is unaffected, leaving the vital rates and population dynamics unchanged., Our results highlight that behavioural change should not automatically be correlated with biological significance when assessing the conservation and management needs of species of interest. This strengthens the argument to use population dynamics targets to manage human activities likely to disturb wildlife. [ABSTRACT FROM AUTHOR]

Abstract: When compared to other organisms, plants are atypical with respect to isoprenoid biosynthesis: they utilize two distinct and separately compartmentalized pathways to build up isoprene units. The co-existence of these pathways in the cytosol and in plastids might permit the synthesis of many vital compounds, being essential for a sessile organism. While substrate exchange across membranes has been shown for a variety of plant species, lack of complementation of strong phenotypes, resulting from inactivation of either the cytosolic pathway (growth and development defects) or the plastidial pathway (pigment bleaching), seems to be surprising at first sight. Hundreds of isoprenoids have been analyzed to determine their biosynthetic origins. It can be concluded that in angiosperms, under standard growth conditions, -phytyl moieties, -triterpenes and -carotenoids are made nearly exclusively within compartmentalized pathways, while mixed origins are widespread for other types of isoprenoid-derived molecules. It seems likely that this coexistence is essential for the interaction of plants with their environment. A major purpose of this review is to summarize such observations, especially within an ecological and functional context and with some emphasis on regulation. This latter aspect still requires more work and present conclusions are preliminary, although some general features seem to exist. [Copyright &y& Elsevier]

Abstract: Recognizing that the sensitivity of NMR is influenced by factors such as conductance and dielectric constant of the sample, we propose the receiving efficiency to characterize how efficiently the NMR signal can be observed from a unit transverse magnetization in a sample under optimal probe tuning and matching conditions. Conveniently, the relative receiving efficiency can be defined as the ratio of the NMR signal induced by a unit transverse magnetization in a sample of interest and a reference solution. Based on the reciprocal relationship between excitation and observation in NMR, the relative receiving efficiency can be correlated with the 90° pulse length (τ 90). In the special case of perfect probe tuning (impedance matched to 50Ω), is inversely proportional to τ 90. Application of the NMR receiving efficiency in quantitative analysis potentially enables a single external concentration reference for almost any sample, eliminating the need to know its exact chemical composition or detailed electromagnetic properties. [Copyright &y& Elsevier]

Abstract: Eukaryotic algae are a very diverse group of organisms that are key components of ecosystems ranging from deserts to the Antarctic. They account for over half of the primary production at the base of food chains. The lipids of different classes are varied and contain unusual compounds not found in other phyla. In this short review, we introduce the major cellular lipids and their fatty acids and then describe how the latter (particularly the polyunsaturated fatty acids, PUFAs) are synthesised. The discovery of different elongases and desaturases important for PUFA production is detailed and their application for biotechnology described. Finally, the potential for algae in commercial applications is discussed, particularly in relation to the production of very long chain PUFAs and biofuel. [Copyright &y& Elsevier]

The article reviews the exhibitions "Buckminster Fuller: Starting With the Universe," at Whitney Museum of American Art from June 26 to September 21, 2008.

Beaked whales can remain submerged for an hour or more and are difficult to sight when they come to the surface to breathe. Passive acoustic detection (PAD) not only complements traditional visual-based methods for detecting these species but also can be more effective because beaked whales produce clicks regularly to echolocate on prey during deep foraging dives. The effectiveness of PAD for beaked whales depends not only on the acoustic behavior and output of the animals but also on environmental conditions and the quality of the passive sonar implemented. A primary constraint on the range at which beaked whale clicks can be detected involves their high frequencies, which attenuate rapidly, resulting in limited ranges of detection, especially in adverse environmental conditions. Given current knowledge of source parameters and in good conditions, for example, with a wind speed of 2 m/s, a receiver close to the surface should be able to detect acoustically Cuvier’s beaked whales with a high probability at distances up to 0.7 km, provided the listening duration exceeds the deep dive interval, about 2.5 h on average. Detection ranges beyond 4 km are unlikely and would require low ambient noise or special sound propagation conditions. [ABSTRACT FROM AUTHOR]

Abstract: Two lipoxygenase isoforms from olive callus cultures were separated from each other. Acetone powders were made to stabilise activity and remove lipids. Separation was then achieved by salt precipitation and ion-exchange chromatography. Both isoforms had comparable activity with linoleic and α-linolenic acid substrates, a basic pH optimum and had molecular masses of around 95kDa. The callus extracts preferentially formed the 13-hydroperoxy products, in keeping with the pattern of volatile derivatives found in olive tissues and oils derived therefrom. [Copyright &y& Elsevier]

The article features architect and industrial designer George Nelson. As stated, his large body of works, from his houses, office furniture, real-time computing systems, to his clients, ranging from small personal commissions to large corporations and states, guarantee him a place in twentieth-century industrial design. According to his biographer, Stanley Abercrombie, Nelson was unconventional and uncommercial but was at times perversely negative and self-destructive. Focus is also given on Nelson's work, his writings and his views regarding his work.

Acanthamoeba castellanii ( A. castellanii) is a common soil- or water-borne protozoon that feeds on bacteria by phagocytosis. A. castellanii can grow between 4 and 32°C and has to adapt quickly to chilling in order to survive. We have identified a Δ12-fatty acid desaturase as key to low temperature adaptation. The activity of this enzyme is mainly increased through gene expression and new protein synthesis. Interestingly, the activity can also be altered independently by dissolved oxygen levels. In addition, we have identified a gene for the Δ12-desaturase, which, when expressed in yeast, catalyses Δ15-desaturation also. Moreover, it is also capable of producing very unusual n-1 polyunsaturated products. [ABSTRACT FROM AUTHOR]

Abstract: For good function, membrane lipids have to be arranged appropriately and be in the correct physical state. In poikilotherms, exposure to cold stress or heat shock can alter membrane properties such that, unless they are corrected quickly, damage and, possibly, death can result. Low temperature stress is countered by modifying membrane lipids such that their average transition temperature is lowered. There are various ways in which this can be achieved but an increase in fatty acid unsaturation is the most common. For heat shock, various changes in lipids have been noted and some defensive strategies involving heat shock proteins noted. In this short review, we will describe recent results where adaptive lipid changes, as a result of temperature stress, have been found. Mechanisms for bringing about such alterations are discussed, together with the contrasting data for different organisms. [Copyright &y& Elsevier]

Abstract: We evaluated the ability of heavy metals (copper, lead) to alter lipid metabolism in four algal lichen photobionts following short term exposure. Metal concentrations (10μM) were equivalent to environmentally relevant levels that have been reported to have effects on intact algae. The algae were grown under normal or deficient phosphate conditions to assess any interactions with the heavy metal stress. Given the frequent sensitivity of lichens to copper and lead, there were surprisingly small changes on lipid metabolism, as assessed by radiolabelling from [1-14C]acetate. The main effects, which were seen in a number of cases, were an overall inhibition of total lipid labelling and a relative increase in the labelling of triacylglycerols in the non-polar fraction. Both of these changes can be viewed as reflecting general toxicity of heavy metals. The Coccomyxa photobiont species were more sensitive than Trebouxia species, which fits with the general distribution of the latter in lichens inhabiting harsh environments. [Copyright &y& Elsevier]

Abstract: Eukaryotic algae are a very diverse group of organisms which inhabit a huge range of ecosystems from the Antarctic to deserts. They account for over half the primary productivity at the base of the food chain. In recent years studies on the lipid biochemistry of algae has shifted from experiments with a few model organisms to encompass a much larger number of, often unusual, algae. This has led to the discovery of new compounds, including major membrane components, as well as the elucidation of lipid signalling pathways. A major drive in recent research have been attempts to discover genes that code for expression of the various proteins involved in the production of very long-chain polyunsaturated fatty acids such as arachidonic, eicosapentaenoic and docosahexaenoic acids. Such work is described here together with information about how environmental factors, such as light, temperature or minerals, can change algal lipid metabolism and how adaptation may take place. [Copyright &y& Elsevier]

1. Many far-ranging bird and mammal species aggregate in colonies to breed, and most individuals remain faithful to one colony. Here, we use modelling to explore the consequences of this site fidelity for the metapopulation dynamics of such species. 2. We develop a spatially explicit model of the annual transfer process between colonies. We apply it to different spatial arrangements of 20 identical colonies and thus demonstrate that connectivity alone can, in the short term, give rise to heterogeneity in colony size. 3. We place the annual transfer model within a state-structured population model and examine the consequences of local and global density dependence for long-term dynamics. For each scenario, we investigate the implications of the strength of site fidelity, the cost of migration and the population's intrinsic growth rate. 4. Our results suggest that, under local density dependence, site fidelity slows down the colonization process and can temporarily trap the entire population in a subset of the available potential colonies. When site fidelity is strong, the metapopulation follows a step-like trajectory. Population growth occurs only rarely because individuals must overcome their site-fidelity to found new colonies. Even though this effect is temporary, it renders the entire metapopulation vulnerable to rare catastrophic collapses. 5. Under global density dependence, site fidelity imposes competition between colonies for the limiting resource. Stochastic events lead to the dominance of certain colonies and the temporary extinction of others. If site fidelity is strong, it can permanently prevent the metapopulation from occupying all available potential colonies. 6. We conclude that, irrespective of the mechanism of population regulation, colonially breeding species that show strong site fidelity are likely to occupy only a portion of the breeding habitat available to them. Journal of Animal Ecology (2005) doi: 10.1111/j.1365-2656.2005.00970.x [ABSTRACT FROM AUTHOR]

Tamoxifen is the hormonal treatment of choice in women who have hormone-dependent breast cancer and its efficacy in those women considered to have a high risk of developing breast cancer, has also been established. γ linolenic acid (GLA) has been shown to decrease the invasion of breast cancer and recent studies have demonstrated that GLA can enhance the oestrogen receptor down-regulation induced by tamoxifen. However, tamoxifen is associated with serious side-effects due mainly to systemic delivery, and targeted delivery of both tamoxifen and GLA would be highly beneficial. This work was a preliminary study for the development of a transcutaneous system to simultaneously deliver both tamoxifen and GLA directly to the breast. Full thickness human skin was dosed with 500 μl saturated solution of tamoxifen in borage oil (25% GLA) and the simultaneous permeation of the two actives determined. There was rapid flux with minimal lag time, the cumulative permeation at 24 h was 764.3±94.2 μg cm−2 for GLA and 5.44±0.67 μg cm−2 for tamoxifen: the latter being comparable to the amount of tamoxifen associated with cancerous breast tissue from a 20 mg oral dose. The ratio of GLA/tamoxifen permeated at different timepoints was quite consistent, both in terms of mass (mean 138, S.D. 15.1) and mols (mean 184, S.D. 20.3). It was determined that 2.5 molecules of GLA were associated with each molecule of tamoxifen in the permeation process, equating to a solvation cage of three molecules of triacylglycerol. This study has demonstrated the feasibility of administering simultaneously tamoxifen and GLA using borage oil as vehicle, which warrants further investigation as a novel topical two-component system in relation to or prophylaxis of those perceived at high risk of developing breast cancer. The study also provides further evidence of the permeation of solvated complexes across skin, rather than discrete penetrant molecules. [Copyright &y& Elsevier]

Arthritis is a common disease in which the end-point results in joint replacement surgery. This article reviews the use of nutraceuticals as alternative treatments for pathological manifestations of arthritic disease. The efficacy of fish oils (e.g. cod liver oil) in the diet has been demonstrated in several clinical trials, animal feeding experiments and in vitro models that mimic cartilage destruction in arthritic disease. In addition, there is some evidence for beneficial effects of other nutraceuticals, such as green tea, herbal extracts, chondroitin sulphate and glucosamine. However, in most cases, there is little scientific evidence at the cellular and molecular levels to explain their mechanisms of action. [Copyright &y& Elsevier]

All ecologists are familiar with uncertainty, at least at the level of whether they should reject a null hypothesis. Uncertainty is, however, pervasive and its characterization is essential if we are to understand our effects on ecosystems. Traditional fisheries management has a poor track record for confronting uncertainty, but most management authorities are now committed to a precautionary approach. As a result, some of the most interesting methods for taking account of uncertainty in ecological systems have been developed by fisheries scientists. These methods evaluate the relative performance of different management procedures with the use of mathematical and statistical models that synthesize knowledge and speculation about the system of interest. Recent advances in computer-intensive statistics have made it possible to combine this approach with model fitting, so that the uncertainties and risks associated with different outcomes of management can be quantified. We show how this methodology can be applied to a range of ecological problems where the advice that scientists provide to decision makers is likely to be clouded by uncertainty. [Copyright &y& Elsevier]

Abstract In 2002 phocine distemper virus (PDV) reappeared in the European harbour seal (Phoca vitulina ) population. This outbreak seems to have followed a similar pattern to the 1988 one which killed almost 60% of individuals in most localities. Harding et al. (2002) suggested that there is a relatively high (18%) risk that recurrent outbreaks of PDV could reduce the European harbour seal population by 90%. We show that incorporating the effects of observation error during population surveys and of the long-term immunity of survivors of morbillivirus outbreaks indicate a much lower level of risk (<1%). This suggests that, while the immediate effects of the disease are dramatic, it is unlikely that recurrent epidemics will pose serious conservation problems for this species under current conditions. [ABSTRACT FROM AUTHOR]

Focuses on the logic of the information age interior design of the White Room at the Data Processing Center of IBM by architect and industrial designer Eliot Noyes. Interface between humans and machines engaged in the synchronic real-time management of spaces or fields; Educational and career background of Noyes; Synchronization of management and design.

Summary • Mosses are particularly able to withstand drought stress. Moreover, abscisic acid (ABA), which is intimately involved during stress in higher plants, has also been implicated in bryophytes. Because membrane damage is a common feature of drought stress, we have studied changes in lipid composition during desiccation and rehydration of the moss Atrichum androgynum and the effect of exogenous ABA on these processes. • In order to correlate any membrane changes with drought stress, we analysed different lipid classes by thin-layer chromatography, fatty acid composition by gas–liquid chromatography and lipid peroxidation. • Water stress caused changes in phosphoglyceride composition consistent with an activation of phospholipase D and of phosphatidylinositol metabolism. Recovery of phosphoglyceride composition towards original levels occurred during rehydration and ABA treatment reduced the overall extent of changes. Reduction in thylakoid lipids and chlorophyll coincided with loss of photosynthesis. • The data show that mosses respond to drought stress similarly to higher plants and that ABA may reduce membrane damage by diminishing the lipid changes. [ABSTRACT FROM AUTHOR]

Interviews professor Carole A. Barone regarding student learning. Discussion on the issue of new models of faculty and staff training; Areas in which higher education can be moved into more rapidly.

Lipid metabolism and the effect of Pb2+ and Cu2+ on this process was studied in the moss Rhytidiadelphus squarrosus collected from both a lead‐contaminated and a non‐contaminated site. Total radiolabelling of lipids from [1‐14C]acetate was similar in both populations and Cu or Pb (1 μM, 10 μM) did not cause much alteration in acute exposure experiments. However, there were significant qualitative changes. Of the major labelled neutral lipid classes, samples from the lead‐polluted site showed a decrease in labelling of triacylglycerols and an increase in wax esters. Acute lead exposure caused similar effects. Cu caused a decrease in the labelling of wax esters and an increase in diacylglycerols. These data suggest that heavy metals cause a change in carbon flux through the acylation reactions associated with the Kennedy pathway. R. squarrosus obtained from the Pb‐contaminated site also showed changes in polar lipid labelling compared to the uncontaminated site. The labelling of phosphatidylcholine was more than halved and replaced by increased labelling of other zwitterionic lipids. The chloroplast glycerolipids were also increasingly labelled. Acute exposure to Pb, however, caused little alteration of labelling patterns within 24 h. R. squarrosus contains high levels of polyunsaturated fatty acids (PUFAs), but moss obtained from the Pb‐polluted site had significantly less PUFAs containing three or more double bonds. Such samples, when incubated with [1‐14C]acetate also showed decreased PUFA labelling. By contrast, acute exposure to Pb produced different results. These data provide a foundation for examining lipid metabolism in bryophytes and the effects of pollution in this important class of organism. The results also emphasize that acute and chronic exposure to heavy metals may produce different effects and that caution must be exercised in extrapolating data from one system to another. [ABSTRACT FROM PUBLISHER]

Discusses whether availability of critical habitat for marine mammals is likely to change in the 21st century. Definition of critical marine habitat; How such habitat may be identified; Implications of the environment to marine-mammal populations.

Titrimetry with electronanalytical endpoint detection was used to determine sequestration capacities of polyphosphates for Fe 2+ and Fe 3+. These methods have the advantage of directly monitoring sequestration of the metal ions. Potentiometry with a divalent ion ion-selective electrode was used to monitor sequestration of Fe 2+; polarography was used to monitor sequestration of Fe 3+. Four commercial liquid polyphosphate formulations, a Zn-orthophosphate, a silicate formulation, two solid polyphosphates, and pyrophosphate were studied. No significant difference was found in sequestration capacities for either metal ion among the polyphosphates. Polyphosphates were found to sequester only about 14% as much Fe 2+ as Fe 3+. The polarographic titration affords an efficient, precise method of studying factors affecting sequestration of iron by polyphosphates. [ABSTRACT FROM AUTHOR]

Focuses on competition in international telecommunications services. Perception on the United States' (U.S.) efforts to promote liberalization in telecommunications services; Speculation on initiatives and approaches that are largely bilateral; Discussion on U.S. policies in the area of international telecommunications.

1. Broad bean (Vicia faba) leaves contain rather high concentrations (about 4% of total fatty acids) of the trans-3-hexadecenoic acid. 2. Amounts of the acid increase with the age of the leaves and are absent from etiolated tissue. 3. Changes in the levels of trans-Δ3-hexadecenoic acid can be produced by subjecting the intact plants to various light/dark periods. 4. Chloroplasts isolated from broad-bean leaves show high rates of fatty acid synthesis from [1-14C]acetate. Synthesis is dependent on coenzyme A and ATP but is insensitive to the addition of exogenous acyl carrier protein. 5. The pattern of acids made includes about 20 % palmitic, 5 % hexadecenoic, 10 % stearic and 60 % oleic. trans-3-Hexadecenoic acid synthesis was most active in chloroplasts from plants exposed to the dark for 5 days and light for 3 days. 6. Arsenite addition inhibited stearate formation by isolated chloroplasts but resulted in a twos fold stimulation of overall synthesis. 7. The rate of fatty acid synthesis by isolated chloroplasts paralleled the changes in endogenous trans-3-hexadecenoic acid levels in the leaves from which they were isolated. [ABSTRACT FROM AUTHOR]

Investigates the crystalline forms of the racemic and enantiomerically pure saturated zwitterionic phospholipids. Variation of ways zwitterionic phospholipids achieve packing into lattices with a minimal residual dipole moment; Conformational alterations manifested by crystalline phospholipid samples during hydration.

Discusses multiple-quantum magic-angle spinning nuclear magnetic resonance (NMR) as a method for the study of quadrupolar nuclei in solids. Energy level diagram of a spin-3/2; Pulse sequence considerations; Triple-quantum mutation behavior calculated for a spin-3/2 in a single-crystal; Angular dependence of triple-quantum excitation profiles.

Abstract: Oil crops are in increasing demand both for food and as renewable sources of chemicals. It is therefore vital to understand how oil accumulation is regulated. Different ways of obtaining such information are discussed with an emphasis on metabolic control analysis. The usefulness of the latter has been well-illustrated by its application to help raise yields in oilseed rape. [Copyright &y& Elsevier]

We present a decision framework to identify when detailed population‐level assessments are required to understand the potential impacts of a disturbance‐inducing activity on a marine mammal population and discuss how the framework can be applied to other taxa. Species at high risk of population‐level effects can be identified using information on the number of individuals that are likely to be disturbed by the activity, total population size, the probability of repeated disturbance, the species' reproductive strategy, and the life stages (e.g., feeding, pregnant, and lactating) of the individuals most likely to be exposed. This hierarchical approach provides those responsible for conducting impact assessments with a time‐efficient, cost‐effective and reproducible workflow that allows them to prioritize their efforts and assign funds to those species with the most pressing conservation needs. A fully worked case study using marine mammals in the vicinity of a naval training activity is supplied. [ABSTRACT FROM AUTHOR]

Polyunsaturated fatty acids (PUFAs), which are divided into n-3 and n-6 classes, are essential for good health in humans and many animals. They are metabolised to lipid mediators, such as eicosanoids, resolvins and protectins. Increasing interest has been paid to the 20 or 22 carbon very long chain PUFAs, since these compounds can be used to form lipid mediators and, thus, avoid inefficient formation of dietary plant PUFAs. The ultimate sources of very long chain PUFAs are algae, which are consumed by fish and then by humans. In this review, I describe the biosynthesis of very long chain PUFAs by algae and how this synthesis can be manipulated for commercial purposes. Ultimately, the production of algal oils is critical for ecosystems worldwide, as well as for human dietary lipids. [ABSTRACT FROM AUTHOR]