Showing papers by "Keele University published in 1990"

Screening for depression during pregnancy with the edinburgh depression scale (EDDS)

Abstract: One hundred women attending a maternity hospital antenatal clinic who were between 28 and 34 weeks gestation completed the EPDS and were then interviewed using a standardized psychiatric interview. EPDS scores were compared with RDC diagnosis of major and minor depression and with total weighted score derived from the interview. The EPDS identified all women with RDC major depression but was less effective in detecting those with RDC minor depression.

Green Political Thought

Abstract: Acknowledgements Preface to the Second Edition Preface to the Third Edition Introduction Part 1: Thinking About Ecologism: sustainable societies reasons to care for the environment crisis and its political-strategic consequences universality and social change lessons from nature left and right: communism and capitalism historical specificity conclusion Part 2: Philosophical Foundations: Ethics: a code of conduct Ethics: a state of being anthropocentrism Part 3: The Sustainable Society: limits to growth possible positions more problems with growth questioning consumption questioning consumption: need questioning consumption: population questioning consumption: technology energy trade and travel work bioregionalism agriculture diversity decentralization and its limits Part 4: Strategies for Green Change: democracy and authoritarianism action through and around the legislature lifestyle communities direct action class conclusion Part 5: Ecologism and Other Ideologies: liberalism conservatism socialism eco-feminism conclusion. Conclusion Bibliography Index

The in vivo micronucleus assay in mammalian bone marrow and peripheral blood. A report of the U.S. Environmental Protection Agency Gene-Tox Program

Abstract: The protocol recommended for the micronucleus assay in mammalian bone marrow has been revised and simplified. The number of sample times has been reduced to one or two, depending upon the dosing protocol. The minimum number of cells to be scored per treatment group has been increased to 20,000 to increase the ability of the assay to detect a doubling of the control micronucleus frequency. Use of both male and female animals is recommended. Scoring of micronuclei in polychromatic erythrocytes of peripheral blood is included as a variation of the bone marrow assay. Published data on chemicals tested by the micronucleus assay have been reviewed and are summarized.

A data envelopment model for aggregating preference rankings

Abstract: This paper presents a general model for aggregating votes from a preferential ballot. The thrust of the model is to accord each candidate a fair assessment in terms of his overall standing vis-a-vis first place, second place, ', kth place votes. The form of the model is a combined index Σj = 1kWjvij where vij is the number of the jth place votes received by the ith candidate. The weights Wj are assumed to form a monotonically decreasing sequence with Wj-Wj + 1 ≥ dj, e. These constraints correspond to the assurance region AR side constraints in the DEA framework. The properties of the model are examined in terms of this discrimination intensity function d, and in the special case that dj, e = e, our model is shown to be equivalent to the consensus models of Borda and Kendall.

Quantitative characterization of the vegetation red edge reflectance 1. An inverted-Gaussian reflectance model

Abstract: An inverted-Gaussian model for the vegetation red edge reflectance is evaluated with respect to its applicability as a simple four-parameter descriptor of vegetation reflectance in the 670 to 800 nm spectral region under a wide range of environmental/measurement conditions. The model has been fitted to laboratory spectral reflectance measurements of single leaves, leaf stacks and needle clump stacks for a number of species. For all of these data the model has been found to provide an effective quantitative representation of the shape and position of the vegetation red edge reflectance in terms of four parameters of physical significance: 1R shoulder reflectance R s, chlorophyll-well minimum reflectance R 0, red edge inflection point wavelength λp and reflectance minimum wavelength λ0. Provided that an appropriate strategy has been adopted to select the initial guess model parameters and the spectral range of reflectance data to be fitted, the values of derived model parameters can be used for a q...

Crisis in education

Abstract: A summary of the workshop convened in May 1971 in Salvador, Bahia, Brazil by the Council on Higher Education in the American Republics to assess current applications of communications technology for the improvement of educational systems in Latin America is given in this document..Against a background which includes: 1) technological asymmetry in which hardware development races ahead of software development and in which technology is not fully integrated into the overall educational matrix; and 2) an educational crisis in the developing world due to scarce resources, rising community expectations, and skyrocketing enrollments, the question of what the new technology has to offer is posed. The report treats some challenges of modern education, the concept of educational technology and sope approaches to it, and the various media forms..It then discusses educational technglogy in action, giving examples from El Salvador, Niger, American Samoa, the Ivory Coast, Great Britain, Spain and Brazil. It closes with a discussion of some issues related to technological implementation and of the prospects for the future..(PB) FILMED FROM BEST AVAILABLE COPY

Methods for the evaluation of biocompatibility of soluble synthetic polymers which have potential for biomedical use: 1 - Use of the tetrazolium-based colorimetric assay (MTT) as a preliminary screen for evaluation of in vitro cytotoxicity

Abstract: A tetrazolium-based colorimetric assay (MTT) was first introduced by Mossman in 1983 to assess the potential of novel antitumour agents, and it has been used here to evaluate the cytotoxicity of several soluble synthetic polymers proposed as drug carriers Polymers including poly-l-lysine (molecular weight 57 000) were incubated (up to 1 mg ml−1) with two human cell lines, hepatocellular carcinoma (HepG2) and lymphoblastoid leukaemia (CCRF), adherent and suspension cells, respectively Tests were carried out in the presence and absence of serum proteins The assay was first modified to optimize the colorimetric profiles produced by the cell lines following incubation with MTT, to increase both the test sensitivity and the reproducibility of the method Polymer toxicity observed using the MTT test was compared with data obtained using other methods; [3H]thymidine or [3H]leucine incorporation and counting cell numbers Poly-l-lysine was very toxic to both cell lines with approximate IC50-values of 60 and 30 µg ml−1 for HepG2 and CCRF, respectively, the values obtained being similar for each of the three different viability methods used In the absence of serum proteins the toxicity of poly-l-lysine increased, the IC50-values falling to 255 µg ml−1 for the adherent and 08 µg ml−1 for the suspension cell line Other polymers such as poly-l-proline, polyethylene glycol, dextran, polyvinylpyrrolidone and poly-l-glutamic acid were not cytotoxic (MTT assay), either in the presence or in the absence of serum proteins The MTT assay is a useful technique for the primary and rapid evaluation of the cytotoxicity of soluble polymers

Anatomy of the cochlear nuclear complex of guinea pig

Abstract: The cyto- and fibre-architecture of the cochlear nuclear complex of the guinea-pig has been studied in serial sections using Nissl, Golgi and combined cell-myelin staining of normal material, and a silver degeneration method after cochlear ablation. The nuclear subdivisions and major cell types can be recognised on the basis of those found in the cat, but there are some differences between the two species in the precise distribution and morphology of the neurons. The rostrodorsal part of the anteroventral cochlear nucleus (AVCN) contains predominantly spherical bushy cells, but these cannot be readily divided into large and small types as in the cat. Globular bushy cells are seen in the caudal region of the AVCN, but the majority occur in the posteroventral cochlear nucleus (PVCN), in an area extending from the nerve root right up to the boundary of the dorsal cochlear nucleus (DCN). The octopus cells constitute a distinct region in the most dorsomedial part of the PVCN underneath the DCN. Giant cells are seen scattered around the nerve root region. Multipolar and small cells are seen throughout the non-granular regions of the ventral cochlear nucleus (VCN) except for the octopus cell area, but occur mainly in the more rostral regions of the PVCN. Small cells occur in greatest abundance in the thin cap area at the dorsal edge of the VCN below a superficial granule cell layer. The latter covers the dorsolateral surface of the VCN, and a lamina of granule cells partially separates the PVCN from the DCN. The DCN can be divided into four layers. The outermost molecular layer (layer 1) is separated from the deeper regions by a prominent layer of granule cells (layer 2) which also contains the pyramidal cells. Molecular layer stellate cells are seen in layer 1 and a staggered row of cartwheel neurons is found at the boundary between layers 1 and 2. Layer 3 contains the basal dendrites of the pyramidal cells and some small (vertical) cells, and is innervated by the descending branches of the cochlear nerve. The deepest layer 4, which contains multipolar cells and giant cells, does not appear to receive this direct cochlear input.

A Dea Model For Measuring The Relative Eeficiency Of Highway Maintenance Patrols

Abstract: A pilot application of Data Envelopment Analysis (DEA) for the measurement of the efficiency of highway maintenance patrols is demonstrated. Selection of pertinent factors is discussed and the potential benefits of the analysis listed. A bounded DEA model is constructed and results are compared to those obtained from a conventional DEA model. The effects of secondary factors on the relative efficiencies of patrols are examined by analyses of sub-groups of Decision Making Units (DMUs), differing in the intensities of the respective factors.

Physiological and behavioural interactions between parasites and invertebrate hosts.

Abstract: Publisher Summary This chapter focuses on the host–parasite interactions that provide new insights into the biochemistry, physiology, ethology, and ecology of the respective partners. This is, particularly, so in the case of parasitic infections of invertebrates for the following reasons: (i) the short generation time and large population size of many invertebrate hosts make them convenient models for study, and the need to understand the role of invertebrate vectors in the transmission cycles of parasitic disease is of particular relevance; and (ii) invertebrates are utilized by a variety of protozoan and helminth parasites as definitive or intermediate hosts in complex life cycles, some of which involve vertebrates. Using examples of parasitic protozoans, helminths, crustaceans, and insects in association with a wide range of invertebrate hosts, strategies, such as the synchronization of host–parasite life cycles, alteration of host growth rates, the impairment of host reproductive capacities, parasite establishment in hosts of different sexes, and alterations in host behavior are examined. A parasitic association succeeds only if the host survives long enough to enable the parasite to complete the particular phase of its life cycle and if the host population is able to persist in time. The mode and degree of integration of a variety of invertebrates and their parasites are also examined.

Biomedical signal processing (in four parts). Part 1. Time-domain methods.

Abstract: This is the first of a series of four tutorial papers on biomedical signal processing. It provides an introduction to terminology and basic ideas for testing for randomness and trend, and for the determination of basic signal properties in the time domain, given the uncertainties associated with the estimation process. Techniques outlined in the paper are: the coherent average, cross-correlation and covariance, autocorrelation and phase-shift averaging.

Size‐Dependent Winter Mortality of Young‐of‐the‐Year White Perch: Climate Warming and Invasion of the Laurentian Great Lakes

Abstract: White perch Morone americana invaded Lake Ontario about 1946 and are now found in Lakes Erie, St. Clair, and Huron, and in Green Bay, Lake Michigan. The indigenous marine distribution of white perch along the Atlantic coast of North America and analysis of climatological data suggest that the northern Gulf of St. Lawrence in the vicinity of the Gasp& Peninsula is too cold to permit white perch to establish local populations or to invade the Great Lakes via the St. Lawrence River. High mortalities of white perch have occurred in Lake Ontario during very cold winters, further suggesting that distribution of white perch is limited by low tolerance of cold temperature. Warmer-than-average summer and winter temperatures during the late 1940s coincided with the invasion of white perch into the Great Lakes via transportation canals in the state of New York. Tolerance of young-of-the-year white perch for low temperature was tested in the laboratory in overwinter experiments at constant temperatures of 2....

New trends in photobiology

Abstract: Considerable interest has been shown in the carotenoids for many years due to their wide ranging roles in photochemistry, photobiology and photomedicine and their possible use as a chemopreventative treatment for cancer. Studies about 20 years ago identified the triplet—triplet absorption of β-carotene; this work was of importance in understanding the protective role of these molecules in photosynthesis and bacterial photosynthesis and in porphyric disease treatment. Recently, attention has turned to the very weak fluorescence of these systems using picosecond measurements; results are related to the antenna role of carotenoids in photosynthesis. Photoisomerization continues to be studied with many of the recent developments based on pump-probe measurements using time-resolved resonance Raman spectroscopy for monitoring both the triplet state and the forbidden (1Ag−*) excited singlet state. Interest is also currently centred on the interaction of singlet oxygen with carotenoids; these studies are of value in photophysics (e.g. determination of the carotenoid lowest triplet energy level) and in photomedicine (e.g. evaluation of the use of carotenoids as chemopreventative drugs).

Chemical communication in insect communities: a guide to insect pheromones with special emphasis on social insects

Abstract: SUMMARY 1Chemical communication plays an important part in the lives of insects, and particularly in lives of those that live in groups or social organizations. 2Chemicals which are used in communication in the general sense are called semiochemicals, and there are a number of subdivisions recognized under this title. 3Pheromones are a category of semiochemicals which are used for communication between individuals of the same species. 4Pheromones are in turn subdivided into primer and releaser pheromones. The former produce a relatively long-lasting physiological change in the receiver, and the latter stimulate the receiver to some immediate behavioural response. 5Far more is known about releaser pheromones at present because they are easier to study. 6Nine categories of releaser pheromone are recognized here, used by both social and non-social insects. 7Sex pheromones are widely used to bring the sexes together for mating, and they have been extensively studied in Lepidoptera. 8Invitation pheromones, encouraging the species to feed or oviposit at an explored site, are not extensively known. 9Aggregation pheromones are designed to bring individuals together into groups which may be temporary in sub-social insects, or permanent in social insects. 10Dispersal or spacing pheromones are used by other species to reduce intraspecific competition for scarce resources. 11Alarm pheromones are a broad and sometimes unclearly defined group which communicate alarm or attack, chiefly in colonial species. 12Trail pheromones, applied to a surface by an individual, to be followed by another, are confined to Hymenoptera, Isoptera and a few Lepidoptera as far as is known. 13Territorial and home range pheromones may be widely distributed, but as yet few of them have been recognized. 14Surface and funeral pheromones are even less well known. Surface pheromones may play a large part in species or colony recognition. 15We can expect the number and complexity of pheromones to be much greater in social insects, a part of the subject which until now has received relatively less attention. 16As our understanding of the subject grows we may expect other categories to be added to this list.

Hydrology of a headwater basin wetland: Groundwater discharge and wetland maintenance

Abstract: The link between groundwater and surface hydrology in a small headwater drainage basin in the zone of glacial deposition of southern Ontario south of the Precambrian Shield was examined for two years. The basin is situated in a discharge zone of a regional aquifer and contains a small treed spring-fed swamp. The swamp exists because of the groundwater and has little effect on the maintenance of streamflow. Groundwater input to the swamp is an order of magnitude larger than precipitation. Groundwater of local and regional origin passes through the swamp by two routes: surface streamlets, where groundwater that emerges at specific seepage points in the swamp is conveyed over the ground surface with little interaction with the swamp itself, and by diffuse seepage in the swamp and through the bed of the stream. While the diffuse seepage input is the smaller component of groundwater it maintains the swamp's saturation. Groundwater input to the swamp from the specific seepage points and diffuse flow varies little over a year; therefore the saturation of the swamp and baseflow from the basin display little seasonal variation compared to other wetland types. The existence of the valley bottom in the headwater basin alters the seasonal and storm hydrology and is important to biogeochemical transformation of emerging groundwater.

Glutathione S‐transferase in human brain

Abstract: The glutathione S-transferases are a complex group of multifunctional enzymes which may detoxify a wide range of toxic substances including drugs and carcinogens. Different isoenzymes vary in substrate specificity, tissue distribution and level of expression during development. Following reports of cell-specific and age-dependent expression in rat brain we have studied, immunohistochemically, expression of the Pi and Alpha class isoenzymes in 10 adult and 21 human fetal brains. Whilst Alpha isoenzyme is expressed only in adult brain, and then only focally, Pi isoenzyme is strongly expressed from as early as 12 weeks gestation. In the adult, expression is localized to choroid plexus, vascular endothelium, ventricular lining cells, pia-arachnoid and astrocytes. In fetal brain, expression is also strong in cells with the morphology of tanycytes and in the cell bodies of radial glia. Neurons are consistently negative. Pi isoenzyme thus localizes to the sites of the blood-CSF barrier, blood-brain barrier, CSF-brain barrier and pia-arachnoid-brain barrier. It is ideally placed to regulate neuronal exposure to potentially toxic substances derived from blood or cerebrospinal fluid. Expression so early in gestation is of significance and may imply a role in protection of the developing human brain.

Provenance and depositional environment of Rhenohercynian synorogenic greywackes from the Giessen Nappe, Germany

Abstract: The Giessen Nappe of the south-eastern Rhenish Massif can be subdivided into a northern group and southern group of Frasnian-?Lower Carboniferous greywackes that differ slightly in their sedimentology, clast petrography, heavy mineral assemblages and bulk geochemistry. Petrographic and geochemical tectonic setting discrimination diagrams indicate that both the northern and the southern Giessen Greywacke groups were derived from a predominantly acidic continental arc source. However, due to the nature of basin development, generation of significant volumes of acidic arc material as a result of southwards directed subduction of Rhenohercynian oceanic crust is considered unlikely. A large part of the arc source may have been contributed by earlier, predominantly acidic, Precambrian terranes together with minor basic igneous and sedimentary components.

Cell physiology of the rat visceral yolk sac: a study of pinocytosis and lysosome function.

Abstract: The rat visceral yolk sac is active in pinocytosis. Macromolecules accumulated by the tissue are, in general, routed to the lysosomes, where they either accumulate (if non-digestible by the lysosomal enzymes) or are degraded to their monomeric components. The yolk sac cells engage in adsorptive pinocytosis, which leads to the preferential uptake of macromolecules bearing certain surface features, such as a hydrophobic or a cationic domain. Substrates that enter the yolk sac by adsorptive pinocytosis can in some cases act as bivalent ligands, carrying in a second substance by "piggy-back" pinocytosis. Pinocytosis and intralysosomal digestion of plasma proteins by the organogenesis-stage rat embryo play an important nutritional role, supplying a high proportion of the embryo's amino acid requirement. Teratogenic effects can be induced by substances that inhibit either pinocytosis or intralysosomal proteolysis at this sensitive stage of gestation.

Post-Taconic blueschist suture in the northern Appalachians of northern New Brunswick, Canada

Abstract: A narrow belt of Late Ordovician-Early Silurian blueschist, at least 70 km long, separates an allochthonous fragment of back-arc oceanic crust of the Middle Ordovician Fournier Group from underlying, rift-related volcanic rocks of the Middle Ordovician Tetagouche Group in northern New Brunswick, Canada. The basalts on both sides of the blueschist belt are predominantly metamorphosed to greenschist facies conditions. The blueschist belt is interpreted to be an out-of-sequence thrust zone that accommodated tectonic transport of higher pressure rocks on top of lower pressure rocks during post-peak blueschist facies metamorphism. The blueschists have higher Fe{sub 2}O{sub 3}/FeO ratios and total iron contents in comparison to otherwise chemically equivalent basalts of the Fournier and Tetagouche Groups that have been metamorphosed into greenschists. The blueschist belt was probably the site of channelized flow of oxidizing fluids during active deformation ina subduction complex formed during the closure of a wide Taconic back-arac basin in Late Ordovician-Silurian time.

Early detection of hearing damage in young listeners resulting from exposure to amplified music.

Abstract: Sixty young subjects in the 15-23 age range, selected on the basis of a questionnaire on the degree of exposure to amplified music, underwent 'high resolution' (4 min per octave) sweep-frequency Bekesy tracking audiometry, and measurement of auditory frequency resolution at 4 kHz using the psychophysical comb-filtered noise masking technique. The more exposed groups had 10-15% wider bandwidths than the least exposed, and this difference achieved significance when subjects having audiometric notches were excluded, or when a subset of exposed subjects was taken in whom subjective evidence was obtained of Temporary Threshold Shift or post-exposure tinnitus. While the most exposed groups did not show significantly greater averaged thresholds, there was in the older age group, a significantly increased prevalence of notches in the audiograms in the 3.5-6 kHz range. We conclude that exposure to amplified music can be harmful, the earliest sign being decrease in frequency resolution, and that early elevation of thresholds is better detected by high-resolution Bekesy tracking (extending over the range 2-8 kHz) than by conventional fixed-frequency audiometry.

Sedimentological response of an alluvial system to Neogene thrust tectonics, Atacama Desert, northern Chile

Abstract: The Llano de la Paciencia is a thrust sheet top basin in which the sedimentological and topographic evolution can be linked to thrust tip propagation. It is an elongate gravel plain which borders the Salar de Atacama, a major intermontane basin in the Andean forearc of northern Chile. The Llano is bounded to the west by the Cerros de Purilactis a Cretaceous–Paleocene sequence uplifted by the Frontal Domeyko Thrust. The eastern margin of the Llano is formed by the Cordillera de la Sal which was uplifted by a linked back thrust-frontal thrust system. The Salar de Atacama is thus divided into a number of discrete sub-basins: the Llano de la Paciencia, the Pampa Visachita and the western sub-Llano which from east-west are bounded by the Cordillera de la Sal, the northern imbricates and the ignimbrite back thrust. Two phases of sedimentological evolution can be distinguished within the Llano on the basis of Quaternary to Recent sediment dispersal patterns. Initially, Phase 1 alluvial fan lobes prograded eastwards into the main Salar de Atacama basin. Subsequently, uplift of the Cordillera de la Sal deflected drainage systems southwards parallel to the structural strike. These Phase 2 alluvial deposits drain into the Salar de Atacama at the lateral termination of the Cordillera de la Sal frontal thrust. In places where thrust tip ramps are emergent within the Llano, gullies have been incised into the drainage pathways. This has resulted in the reworking of the early Phase 1 gravels and progradation of the Phase 2 fan lobes. The evolution of the Llano de la Paciencia illustrates the close link between topography and syntectonic alluvial drainage patterns in an arid intermontane basin.

Is pregnancy a time of changing drinking and smoking patterns for fathers as well as mothers? An initial investigation.

Abstract: This paper describes changing smoking and drinking patterns before and during pregnancy in 313 expectant couples. Fathers were more likely to drink and smoke more heavily than mothers throughout. Before pregnancy in only 42% of couples were both partners safe drinkers and non-smokers. This increased to 50% during pregnancy. Most mothers reduced alcohol consumption during pregnancy and although about half of the fathers also changed their drinking patterns, only about a fifth decreased their consumption. Levels of paternal and maternal drinking in pregnancy were positively associated with pre-pregnancy levels. Rates and levels of both maternal and paternal smoking declined in pregnancy. There was a positive association between partners of both the prevalence and level of drinking and smoking between partners. There was some indication that mothers were more likely to reduce smoking and drinking if their partner joined them in doing so. Risk drinking in couples was more common in those who were older and of higher social status, but smoking was more common among the younger couples of lower social status.

A simple method for analysis of insect cuticular hydrocarbons.

Abstract: Cuticular hydrocarbons from tiny pieces of insect cuticle can be analyzed directly by gas chromatography without solvent. The cuticle, sealed in a glass capillary, is introduced into the heated injector area of a gas Chromatograph, and the glass capillary crushed after heating for 4 min. Linked gas chromatography-mass spectrometry can be performed on selected parts of individual insects, such as an antenna, leg, or abdominal sclerite, to give qualitative and quantitative analysis of the substances on a small area of the body.

Sex differences among partner preferences: Are the sexes really very similar?

Abstract: The question as to what type of individual we prefer in a “romantic” partner has stimulated a long history of research, with much of the present debate centering around the issue of the sex differences in partner preferences. In the studies described in this paper, two groups of participants completed a variety of different questionnaire schedules indicating their preferences for a partner. In study 1, 216 single students demonstrated a prevailing desire for a kind, considerate, and honest partner who displayed a keen sense of humor. Consistent with the hypothesis, there were no clear sex differences evident in these results. In study 2, 76 dating agency members completed a similar schedule examining partner preferences. Here again, preferences were similar across the sexes, although men preferred the submissive and introverted partner and stressed the importance of physical appearance in a mate. The general discussion considers the implications of these findings in the light of previous research on partner preferences.