bluuebunny/crossref_metadata_2025 huggingface dataset:
The experiences of ethics committee members: contradictions between individuals and committees
Authors: Elliott L , Hunter D
Published: May 2008

The current system of ethical review for medical research in the United Kingdom is changing from the current system involving large committees of 7–18 members reviewing every individual application to a system involving pre-review by small sub-committees of National Research Ethics Officers (NREAs), who have a remit to approve studies if they believe there are no material ethical issues imposed by the research. The reliability of this new system depends on the reliability of the NREAs and in particular the ability of small groups to effectively identify and appropriately assess the seriousness of all the material ethical issues that may be posed by an application. There is anecdotal evidence to suggest that many individual research ethics committee members have had experience of believing that a study presents no material ethical concerns, then on reaching the committee and discussing the application they realise that the committee feels it does present significant ethical concerns. If this is the case then this casts doubt on the reliability of NREAs or small groups to effectively identify ethically problematic research and appropriately respond to this to protect research participants. In this paper we describe a small questionnaire based piece of research carried out to assess how common this and other relevant experiences are.
Ethical decision-making, passivity and pharmacy: Figure 1
Authors: Cooper R J , Bissell P , Wingfield J
Published: May 2008

Background:

Increasing interest in empirical ethics has enhanced understanding of healthcare professionals’ ethical problems and attendant decision-making. A four-stage decision-making model involving ethical attention, reasoning, intention and action offers further insights into how more than reasoning alone may contribute to decision-making.

Aims:

To explore how the four-stage model can increase understanding of decision-making in healthcare and describe the decision-making of an under-researched professional group.

Methods:

23 purposively sampled UK community pharmacists were asked, in semi-structured interviews, to describe ethical problems in their work and how they were resolved. Framework analysis of transcribed interviews utilised the four decision-making stages, together with constant comparative methods and deviant-case analysis.

Results:

Pharmacists were often inattentive and constructed problems in legal terms. Ethical reasoning was limited, but examples of appeals to consequences, the golden rule, religious faith and common-sense experience emerged. Ethical intention was compromised by frequent concern about legal prosecution. Ethical inaction was common, typified by pharmacists’ failure to report healthcare professionals’ bad practices, and ethical passivity emerged to describe these negative examples of the four decision-making stages. Pharmacists occasionally described more ethically active decision-making, but this often involved ethical uncertainty.

Discussion:

The four decision-making stages are a useful tool in considering how healthcare professionals try to resolve ethical problems in practice. They reveal processes often ignored in normative theories, and their recognition and the emergence of ethical passivity indicates the complexity of decision-making in practice. Ethical passivity may be deleterious to patients’ welfare, and concerns emerge about improving pharmacists’ ethical training and promoting ethical awareness and responsibility.
“Writing is a way of saying things I can’t say”—therapeutic creative writing: a qualitative study of its value to people with cancer cared for in cancer and palliative healthcare
Authors: Bolton G
Published: May 2008

This paper reports on a therapeutic creative writing project undertaken at King’s College London and University College Hospital London, funded by Arts Council England. The project sought to increase understanding of experiences of personal expressive and explorative writing by cancer patients receiving palliative care. Narrative methods were used to analyse and interpret patients’ written and oral (transcripts of semistructured interviews) responses, researchers’ field notes and written responses of staff. These indicated that writing: (1) facilitated patients’ ability and opportunity to discover what they thought, felt, remembered; (2) enhanced their awareness of, and ability to express, issues to which focused attention needed to be paid; and (3) offered satisfaction and fulfilment of creative expression and exploration and the production of writings which to them and close others were vital. Illuminatively drawing upon patients’ writings and responses, this paper is underpinned by discussion of therapeutic writing and its relationship to creative writing, with reference to a range of previous research.
Evidence-based medicine? Patient case studies in English surgical treatises, 1660–1700: Table 1
Authors: Sandassie S
Published: May 2008

The implications of the presence of case information included in English surgical treatises published from 1660 to 1700 are discussed. While such casework has been frequently examined and cited, the phenomenon of including case information in treatises has yet to be studied in any depth. The context, presentation and origins of the case information are discussed, and the reasons behind the inclusion of casework are explored in terms of “blame-narratives”, teaching models and evidence-based medicine. It was found that, while the reasons behind the inclusion of case information varied, English surgeons practised evidence-based medicine. This finding is significant, as it proposes that evidence-based medicine was practised a century earlier than—and across the Channel from—its supposed first emergence in modern medical practice.
The inference from a single case: moral versus scientific inferences in implementing new biotechnologies
Authors: Hofmann B
Published: May 2008

Are there similarities between scientific and moral inference? This is the key question in this article. It takes as its point of departure an instance of one person’s story in the media changing both Norwegian public opinion and a brand-new Norwegian law prohibiting the use of saviour siblings. The case appears to falsify existing norms and to establish new ones. The analysis of this case reveals similarities in the modes of inference in science and morals, inasmuch as (a) a single case functions as a counter-example to an existing rule; (b) there is a common presupposition of stability, similarity and order, which makes it possible to reason from a few cases to a general rule; and (c) this makes it possible to hold things together and retain order. In science, these modes of inference are referred to as falsification, induction and consistency. In morals, they have a variety of other names. Hence, even without abandoning the fact–value divide, there appear to be similarities between inference in science and inference in morals, which may encourage communication across the boundaries between “the two cultures” and which are relevant to medical humanities.
Camille Claudel: trajectory of a psychosis
Authors: Cooper B
Published: May 2008

The French sculptor Camille Claudel at about the age of 40 developed a psychotic illness that proved to be chronic. Delusions of persecution, focused on her former mentor and lover Auguste Rodin, gradually became systematised until they dominated her life completely. She abandoned artistic work, withdrew into social isolation and lived alone in conditions of squalor and severe self-neglect until eventually, after her father’s death, she was committed to an asylum and spent the remainder of her life in institutional confinement. Only within the past 20 years has her achievement been recognised and her fate drawn wide sympathy. Previous psychiatric studies have dismissed or downplayed the significance of Camille’s adverse life experiences for her case history. The present reassessment, drawing on modern interactionist models of the genesis and course of psychosis, sets out to place both her creative drive and her mental instability within a broader life-course perspective and to arrive at a more balanced judgement of the case.
The year of magical thinking: Joan Didion and the dialectic of grief
Authors: Brennan F , Dash M
Published: May 2008

Joan Didion is a prominent American writer. In late 2003, while her only child lay critically ill, her husband, John, died suddenly. Theirs was a marriage of great intimacy and love. Grief enveloped her. Eventually she began to write an account of the first 12 months of her bereavement and the vigil for her child:The year of magical thinking. Raw, insightful and challenging, it is a rich, generous and graceful document. Didion draws on the literature of grief, personal and professional. Here, those readings are examined and reflections are made on the singular, unique grief of the author in the context of current theories on bereavement.
Genetic susceptibility to the respiratory effects of air pollution
Authors: Yang I A , Fong K M , Zimmerman P V , Holgate S T , Holloway J W
Published: May 2008

There is large variation between individuals in their response to air pollutants. This review summarises the existing evidence that genetic factors influence the mechanisms of lung injury caused by air pollutants. Genetic association studies have compared the adverse effects of air pollutants between subjects with specific genotypes in biologically relevant genes. In human studies of ozone exposure, polymorphisms in oxidative stress genes (NQO1, GSTM1, GSTP1) modify respiratory symptoms, lung function, biomarkers and risk of asthma. Inflammatory gene polymorphisms (TNF) influence the lung function response to ozone, and the effect of different levels of ozone on the development of asthma. Polymorphisms in oxidative stress genes (GSTM1, GSTP1) alter the response to combined exposure to ragweed pollen and diesel exhaust particles. Importantly, polymorphisms in an oxidative stress gene (GSTM1) have predicted patients with asthma who benefit from antioxidant supplementation in Mexico City, which has chronically high ozone exposure. Genetic linkage studies of families have not been feasible for studying the effects of air pollution in humans, but some progress has been made with pedigrees of specially bred mice, in identifying chromosomal regions linked to effects of ozone or particles. A high priority now, in addition to avoiding exposure in the most susceptible people, is to clearly identify the most effective and safe chemopreventive agents for individuals who are genetically susceptible to the adverse effects of air pollution (eg, antioxidants to be taken during high ozone levels).
Relationship between Food, Fat, Sexual Maturation, and Spawning Time of Baltic Herring (Clupea harengus membras) in the Archipelago Sea
Authors: Rajasilta Marjut
Published: May 2008

The effect of nutritional status on gonad maturation and timing of spawning was examined in the Baltic herring (Clupea harengus membras) in the Archipelago Sea. Fish were collected from overwintering areas in December and from the spawning grounds in May–July. Muscle fat content, amount of mesenteric fat, and condition factor were used as indicators of nutritional status of fish. In winter, fish were highly variable with substantial individual variation in nutritional status, gonad stage, gonad weight, and gonadosomatic index (GSI). Gonad weight was related to fat content, suggesting a close relationship with fish nutritional status and maturation rate. Spawning fish were separable into early and late spawners according to fat content, gonad weight, and GSI but not according to length. The spawning shoals consisted of mixtures of fish of all sizes. I concluded that in the study area, individual maturation cycles vary and timing of spawning is primarily determined by the feeding conditions prior to spawning.
Cadmium and Zinc Uptake by Two Species of Aquatic Invertebrate Predators from Dietary and Aqueous Sources
Authors: Timmermans Klaas R. , Spijkerman Elly , Tonkes Marcel , Govers Harrie
Published: May 2008

Cadmium and Zn uptake rates via food and water were determined under laboratory conditions for two species of freshwater invertebrate predators. Water mites (Limnesia maculata) and caddisfly larvae (Mystacides spp.) were exposed for 4 wk to either contaminated chironomid larvae (Chironomus riparius, 288–639 μg Cd∙g−1 or 778–1152 μg Zn∙g−1) or contaminated water (0.1 mg Cd∙L−1 or 1.0 mg Zn∙L−1). Cadmium was readily accumulated in the two species from both dietary and aqueous sources. A clear difference between exposed and untreated organisms was established. Zinc uptake was generally lower than that of Cd, resulting in small differences between exposed and nonexposed organisms. Cadmium uptake from food and Zn uptake from water dominated in both species. It is concluded that, in addition to uptake of free metal ions from aqueous sources, invertebrate predators can accumulate trace metals from their food. This is an underestimated source of contamination for freshwater invertebrate predators. Changes in internal metal concentrations in the predators are described with a first-order one-compartment uptake model. This model was appropriate where steady-state conditions were approached. When uptake continued throughout the experimental period, uptake rate constants were estimated using linear regression.
Zooplankton Retained in Sequential Sediment Traps along the Beaufort Sea Shelf Break during Winter
Authors: Forbes J. R. , Macdonald R. W. , Carmack E. C. , Iseki K. , O'Brien M. C.
Published: May 2008

Zooplankton retained in four sediment traps deployed along the shelf break of the eastern Beaufort Sea, from September 1987 to March 1988, were used to investigate temporal and regional variations of the zooplankton community during winter. Despite trap selectivity, the species composition indicated that both the shelf community and Atlantic water community of the deep Arctic Ocean are excluded from the shelf break at this time of year. There was no evidence of off-shelf transport during the study period. Taxa collected, predominantly pteropods (Spiratella helicina) and calanoid copepods, were typical of the community in the upper 200 m of the central Arctic Ocean. The abundance of pteropods was strongly associated with ice cover. The easternmost trap, located at the entrance to Amundsen Gulf, had a distribution of animals distinct from those in the other traps. It lay outside the influence of the Beaufort Gyre and Beaufort Undercurrent, which apparently affected the other locations.
Influence of Tributary Spatial Position on the Structure of Warmwater Fish Communities
Authors: Osborne Lewis L. , Wiley Michael J.
Published: May 2008

We found a significant and positive relationship between fish species richness and four measures of stream size (drainage area, stream order, link magnitude, and downstream link) in three Illinois drainage basins. Downstream link (incorporating both stream size and size of stream at the next downstream confluence) explained the greatest portion of the variance. This suggests that downstream processes significantly influence the structure of fish communities inhabiting warmwater streams. Significantly higher numbers of fish species were collected from tributary streams (< 259 km2 drainage area) located lower in a drainage network and connected to a main channel system than from similarly sized streams located in the headwaters of a drainage network. The difference in species richness among station treatments was not due to a difference in the number of individuals collected among treatments. We were unable to accept or reject the hypothesis that differences in fish species richness were due to differences in physical habitat. The immigration–extinction hypothesis appears to provide a plausible explanation for the observed pattern in fish community structure within a drainage. The location of a stream channel within a network may provide a general template for fish community structure in warmwater drainages by regulating potential species richness.
Large Woody Debris and Salmonid Habitat in a Small Coastal British Columbia Stream
Authors: Fausch Kurt D. , Northcote Thomas G.
Published: May 2008

Sections of a small coastal British Columbia stream that had previously been cleaned of large woody debris (LWD) were compared with sections where most debris was left and with others where debris had been relatively undisturbed for at least 40 yr. Three sections where debris had been removed had simple habitat that was less sinuous, wider, and shallower and had less pool volume and overhead cover than four sections with more complex habitat where debris was retained. Habitat in four relatively undisturbed sections was generally similar to complex sections. Most pools in all sections were scour or plunge pools formed by LWD or large roots oriented perpendicular to the flow or angled downstream. Standing crop (kolograms per hectare) and individual weights of age 1 + and older coho salmon (Oncorhynchus kisutch) and cutthroat trout (O. clarki) were significantly greater (P < 0.02) in complex than in simple sections. Biomass of age 1 + and older salmonids was closely related to section pool volume (r2 = 0.92, P = 0.0006). Projections based on this model and average habitat conditions suggest that during 1990 a total of 8.0 kg of salmonid biomass, 5 times the current standing crop, was forgone in the 332-m simple reach due to prior debris removal.
Production and Vertical Migration ofCeratium hirundinellain Relation to Phosphorus Availability in Eau Galle Reservoir, Wisconsin
Authors: James William F. , Taylor William D. , Barko John W.
Published: May 2008

Seasonal production of Ceratium hirundinella and its diel migratory patterns were examined in relation to phosphorus (P) availability in eutrophic Eau Galle Reservoir, Wisconsin (USA). During mid-June, hypolimnetic P gradients (0.030–1.045 mg∙L−1) developed as internal P loading was high (14.7–18.0 mg∙m−2∙d−1). Ceratium migrated as much as 4 m into the upper hypolimnion at night. Subsequent increases in Ceratium biomass, gross primary productivity, and chlorophyll a indicated retrieval of hypolimnetic P for production. During early July, anoxia restricted vertical migration of Ceratium into the hypolimnion. Surplus cellular P was low during this period, while alkaline phosphatase activity increased to a maximum, suggesting P limitation of Ceratium production. During late July and August, P-rich interflows from the Eau Galle River entered the reservoir at the base of the epilimnion. Ceratium migrated into these interflows at night, with corresponding increases and decreases in surplus cellular P and alkaline phosphatase activity, respectively. Ceratium production increased to a maximum in early September, following these periods of high external P input. These results directly support the hypothesis that Ceratium can access multiple P sources through vertical migration.
Inferring the Summer Distribution of Migratory Pacific Hake (Merluccius productus) from Latitudinal Variation in Mean Lengths-at-Age and Length Frequency Distributions
Authors: Smith Barry D. , McFarlane Gordon A. , Saunders Mark W.
Published: May 2008

Average summer distribution of abundance and biomass for the migratory population of Pacific hake (Merluccius productus) is described by age, length, and latitude, based on a model proposing that (1) changes in mean length-at-age with latitude and (2) the nonnormal (skewed to the right) appearance of length-at-age distributions near southwest Vancouver Island could be caused by length-dependent migration velocities and changing migration velocity with latitude. Our model uses mean length-at-age data collected annually near four latitudes from California to Vancouver Island, length frequency data collected annually near southern Vancouver Island from 1978 until 1988, and hydroacoustic data collected triennialiy from 1977 until 1986. We conclude that (1) hake slow their northward migration from the spawning grounds off southern California as they approach the productive feeding grounds off southwestern Vancouver Island, (2) older (larger) hake migrate further north than younger (smaller) hake, and (3) older hake are more abundant in Canadian waters than younger hake. Although all three conclusions have previously been partly substantiated, we show that seemingly undramatic patterns in the mean, variance, and distribution of lengths-at-age can be remarkably revealing about the distribution of a migrating fish population.
Environmental Fate of Polychlorinated Dibenzo-p-dioxins in Lake Enclosures
Authors: Servos Mark R. , Muir Derek C. G. , Webster G. R. Barrie
Published: May 2008

The environmental fate of 1,3,6,8-tetra- (T4CDD) and octachlorodibenzo-p-dioxin (O8CDD), two major dioxin congeners emitted into the environment, was studied in large (40 m3) lake enclosures at the Experimental Lakes Area in northwestern Ontario. The polychlorinated dioxins (PCDDs) were added to replicate enclosures as a sediment slurry at a nominal concentration of 58–59 ng∙L−1. Both congeners partitioned/settled rapidly to the surficial sediments where they persisted over the 2 yr of the study. Initially the concentrations of the T4CDD in water were higher than those of O8CDD, but the concentrations of the T4CDD in the water column declined more rapidly than those of O8CDD, with t1/2 of 2.6 ± 0.2 and 4.0 ± 0.3 d, respectively. Approximately 10–15% of the T4CDD and < 1% of the O8CDD detected in the water column during the first 48 h were determined to be truly dissolved. The rapid partitioning of O8CDD and to a lesser extent T4CDD to dissolved and particulate organic matter in the water column and sediments limited their bioavailability. Increased retentive capacity of the higher chlorinated PCDDs may explain the pattern of increasing concentration of PCDDs in sediments with increasing chlorine substitution observed in the Great Lakes and other aquatic environments.
Climatic Influence Linking Copepod Production with Strong Year-Classes in Sablefish, Anoplopoma fimbria
Authors: McFarlane G. A. , Beamish R. J.
Published: May 2008

Stomach contents from first-feeding larval sablefish (Anoplopoma fimbria) comprised mainly calanoid copepods. Along the west coast of Vancouver Island, these copepods were the dominant zooplankton at the depth that sablefish larvae developed. We propose that strong year-classes in sablefish populations occur when there is exceptional production of copepods. The periods of exceptional copepod production appear to be correlated with climate and ocean conditions.
Seasonal Reproduction and Plasma Levels of Sex Steroids and Vitellogenin in Atlantic Halibut (Hippoglossus hippoglossus)
Authors: Methven David A. , Crim Laurence W. , Norberg Birgitta , Brown Joseph A. , Goff Gregory P. , Huse Ingvar
Published: May 2008

Atlantic halibut (Hippoglossus hippoglossus) collected off Newfoundland first mature at about 80 cm fork length (FL) for males and about 115–120 cm FL for females. Captive Newfoundland halibut did not release milt or eggs or have detectable levels of estradiol-17β or 11-ketotestosterone until exceeding 80 cm (males) and 115–120 cm (females). Estradiol-17β and testosterone increased to highest levels in females during gonadal recrudescence before spawning. Lower levels were observed in spawning fish. Vitellogenin (VTG) levels were highest in spawning fish. A sudden drop in estradiol-17β and VTG preceded release of the first batch of eggs. Estradiol-17β, testosterone, and VTG fluctuated with release of successive batches of eggs. Male halibut started to mature during fall and early winter, as indicated by increased testosterone and 11-ketotestosterone and abdominal swelling. Milt was first released in January and February when testosterone and 11-ketotestosterone were near maximum levels. Hence, rising levels of plasma sex steroids and VTG in fall indicate that reproductive activity is underway 1–2 mo before any noticeable swelling of the abdomen. Individual maturing halibut can be sexed by rising levels of estradiol-17β and VTG (females) and 11-ketotestosterone (males) in late fall and early winter.
Evolution of Lake Whitefish (Coregonus clupeaformis) in North America during the Pleistocene: Genetic Differentiation between Sympatric Populations
Authors: Bodaly R. A. , Clayton J. W. , Lindsey C. C. , Vuorinen J.
Published: May 2008

We use electrophoretic data on dehydrogenase enzymes to examine the relatedness of sympatric populations of lake whitefish (Coregonus clupeaformis) and provide evidence for the existence of a glacial refuge race of lake whitefish in eastern North America. This Acadian race is presently found in New England, the Gaspé peninsula of Québec, and New Brunswick. It probably survived glaciation in a refugium on the exposed coastal plain of northeastern North America. In areas of contact, most glacial races appear to introgress and do not coexist in sympatry. However, sympatric pairs of populations occur (or occurred) within the ranges of all races of lake whitefish. Allele frequencies for at least one enzyme system examined for most sympatric pairs were significantly different, indicating that these sympatric populations are wholly or substantially, isolated reproductively from each other. Both members of the population pairs examined in the Yukon Territory, Ontario, and Labrador were genetically characteristic of the glacial races of their region. This suggests that they are not the result of speciation due to geographic isolation in different glacial refugia. Thus, their origin appears to be postglacial, but may be older if present genetic similarities are due to recent gene flow between sympatric forms.
Seasonal Changes in Habitat Use by Juvenile Coho Salmon (Oncorhynchus kisutch) in Oregon Coastal Streams
Authors: Nickelson Thomas E. , Rodgers Jeffrey D. , Johnson Steven L. , Solazzi Mario F.
Published: May 2008

Habitat use by juvenile coho salmon (Oncorhynchus kisutch) during spring, summer, and winter was examined in Oregon coastal streams. Coho salmon fry were most abundant in backwater pools during spring. During summer, juvenile coho salmon were more abundant in pools of all types than they were in glides or riffles. During winter, juvenile coho salmon were most abundant in alcoves and beaver ponds. Because of the apparent strong preference for alcove and beaver pond habitat during winter and the rarity of that habitat in coastal streams, we concluded that if spawning escapement is adequate, the production of wild coho salmon smolts in most coho salmon spawning streams on the Oregon Coast is probably limited by the availability of adequate winter habitat.
Regional Differences in Otolith Morphology of the Deep Slope Red Snapper Etelis carbunculus
Authors: Smith M. Kimberly
Published: May 2008

Sagittal otoliths from four populations of the Pacific deep slope red snapper Etelis carbunculus Cuvier were compared using Fourier descriptors and other shape indices, linear proportions, and dry weight. Otoliths from Hawaii, Vanuatu, Fiji and French Polynesia and a small number from the Commonwealth of the Northern Marianas Islands (NMI) were examined. Regional shape and weight characteristics were distinguishable, despite the wide range of individual variation and limited available size range from some regions. Size-specific differences in otolith shape were found for the four regions for which a sufficient sample was available. Otoliths from Hawaii, French Polynesia, and NMI showed a significant shape affinity. Otoliths from Fiji and Vanuatu were similarly shaped and were distinct from those from the other three regions. Interregional otolith shape affinities for the stocks examined parallel similarities in maximum size and growth rate from the literature, suggesting that growth rate may influence otolith shape. Observed trends in otolith weight as a function of fish length support growth-related regional differences in otolith shape.
Body Size and the Ontogeny of the Functional Response in Fishes
Authors: Miller Thomas J. , Crowder Larry B. , Rice James A. , Binkowski Fred P.
Published: May 2008

The development of foraging abilities is crucial to the survival and subsequent recruitment of young fishes. We examined experimentally the notion that the foraging abilities of species are so different that useful generalizations across taxa are impossible. We investigated the ontogeny of feeding, reflected in their functional responses, in three Great Lakes' fishes, alewife (Alosa pseudoharengus), yellow perch (Perca flavescens), and bloater (Coregonus hoyi). No strong evidence of species-specific differences in the ontogeny of feeding ability was found. A single size-based relationship explained 52–88% of the variation in the parameters of the functional response equation. We conclude that interspecific differences in feeding abilities of larval fishes may have been overemphasized, and we suggest that interspecific differences should only be addressed within a size-based framework. This approach appears to provide an acceptable basis for first-order predictions of foraging abilities across taxa, for the identification of exceptional abilities which may lead to advances in the understanding of foraging ability, and for estimating foraging rates for important species for which data are now lacking.
Responses of Immature Blackflies (Diptera: Simuliidae) to Experimental Pulses of Acidity
Authors: Chmielewski C. M. , Hall R. J.
Published: May 2008

An investigation to determine the responses of immature blackflies to experimental pulses of acidity simulating snowmelt episodes was conducted. Five species of mature blackfly larvae were subjected to 3- or 4-d experimental pH depressions to approximately 4.0 or 3.5 in stream channels. Differences among species in response to acidity were observed. All species except Simulium vittatum and possibly S. venustum were able to tolerate pH depressions to approximately 4.0, while only Cnephia dacotensis and possibly S. decorum were able to tolerate pH depressions to approximately 3.5. The survival of the larvae (only late instars were tested) was significantly affected by the acidity, while pupal survival generally was not. The rate of pupation, however, was decreased in the acidified channels, resulting in decreased emergence there also. More abnormally formed pupae developed in the acidified channels, suggesting that pupation following snowmelt ensures survival of these species.
Displacements of footings on sand under eccentric and inclined loads
Authors: Georgiadis M. , Butterfield R.
Published: May 2008

Results of an investigation of the response of footings on sand, under eccentric and inclined loads, are presented. Apparatus was constructed that could simultaneously apply loads to footings at any eccentricity and inclination, without imposing restraints on the footing displacements. The experimental results are interpreted, compared with published data, and a method for predicting vertical and horizontal displacements and rotations of loaded footings on sand developed. At low load levels the analysis generates the elastic half-space solution, which is then augmented to provide the complete nonlinear response of the footing. In addition, interaction diagrams between the vertical loads, horizontal loads, and moments that cause failure of the footing are presented. Key words: footing, sands, eccentric loading, inclined loading, displacement, rotation, bearing capacity.
A compressive strength criterion for anisotropic rock materials
Authors: Ashour Hamdy A.
Published: May 2008

This paper proposes a general compressive strength criterion for anisotropic rock materials under multiaxial states of stress. The proposed criterion is a generalization of the Von Mises' criterion for yielding of ductile metals, which has also been used previously as a strength criterion for brittle fracture in the spirit of both being limits of linear elastic behavior. The presently proposed criterion takes into consideration the effects of the confining pressure, the various stress components, and the material anisotropy on rock material failure in a multiaxial stress state. To verify the applicability of the proposed criterion, it has been used to construct the failure envelopes for several types of rock materials. Consequently, the constructed failure envelopes and the corresponding experimental results have been compared. In all cases, a close agreement with the experimental results has been achieved. This result demonstrates the versatility and applicability of the proposed strength criterion in representing the compressive strength behavior of anisotropic rock materials under complex multiaxial states of stress. Key words: strength, rock materials, anisotropy.
Stress characteristics for shallow footings in cohesionless slopes
Authors: Graham J. , Andrews M. , Shields D. H.
Published: May 2008

Footings placed at shallow depth in bridge approach embankments can be used to reduce the cost and to improve the performance of bridge supports. The embankments frequently terminate in slopes dropping to underpass level, and the footings therefore have lower capacity than that for footings on level ground. The needed design procedures have not been well validated.The paper describes a new solution using the method of stress characteristics for footing capacity in cohesionless slopes. The soil is assumed to have c = 0, [Formula: see text] = constant, γ > 0. Particular attention is paid to modelling the asymmetric nonfailing zone immediately beneath the footing. Solutions for various slope angles and friction angles have been obtained for footings placed at the crest of the slope with D/B = H/B = 0, and for H/B = 0.5, 1.0, and 2.0; D/B = 0.5 and 1.0. The theoretical bearing capacities are compared with experimental values from two series of laboratory tests. Key words: bearing capacity, footings, failure, bridge abutments, slopes, sand, cohesionless, stress characteristics.
The creep of ice measured with the pressuremeter
Authors: Kjartanson B. H. , Shields D. H. , Domaschuk L. , Man C.-S.
Published: May 2008

The pressuremeter has the potential to measure the creep parameters of ice in situ, that is to say, in the field, in ice at its natural temperature and natural stress environment, and in ice that has not been disturbed by sampling and handling. To prove that the pressuremeter can in fact be used to measure creep properties, a series of pressuremeter tests were run in the laboratory in poly crystalline ice at −2°C. It was found that (1) the particular pressuremeter used maintained an ability to measure creep deformation accurately over a period of 7 weeks, (2) the test results agree for the most part with the findings of other investigators who have used uniaxial compression tests, and (3) the pressuremeter brings into question at least one of the more common assumptions regarding primary creep. Key words: ice, freshwater, creep, pressuremeter.
Subsoil investigation of ice lensing at the Calgary, Canada, frost heave test facility
Authors: Carlson L. E. , Nixon J. F. (Derick)
Published: May 2008

Several frost heave mitigation modes were studied at the Calgary, Canada, chilled pipeline frost heave test facility. These included deeper burial (to increase the pressure on the frost front below the pipe) and replacement of the silty soil around the pipe with gravel for a noninsulated pipe. Frost heave at the deep-burial section and at the gravel section was less than the heave at a control section. Other pipe sections tested the effects of insulation of the pipe on the long-term frost heave, as well as the effects of replacing the silt around an insulated pipe with gravel. Summer thawing of the frost bulb around the insulated pipe results in seasonal thaw settlement of the pipe, thus reducing the long-term pipe heave, at least for the warmer ground temperature environment at the Calgary facility.Thermal simulations of the frost bulb growth and predictions of frost heave using the segregation potential model agree well with the observations.Recent excavation of two frost bulbs in silty soil led to field observations of the interior of the frost bulbs, and subsequent laboratory analysis of frost bulb samples. Ice distribution was logged and photographed following excavation of each frost bulb. Key words: frost heave, pipeline, silt, mitigation, instrumentation, field observations.
Behaviour of vertical shafts: reevaluation of model test results and evaluation of field measurements
Authors: Wong R. C. K. , Kaiser P. K.
Published: May 2008

The use of the convergence–confinement method with the inclusion of gravity effects was previously proposed as an analytical tool to predict the behaviour of vertical shafts. Results from this approach compared well with those obtained by finite element numerical simulations. In this paper, this method is evaluated by comparison of predictions with the performance of several instrumented, full-scale and model shafts. The evaluation confirms that the proposed method provides satisfactory predictions of shaft behaviour (i.e., support pressure – radial displacement relationship) in various soil types. It is also shown that the actual support pressures, monitored in the model tests and in the field, are generally higher than those predicted by conventional design methods. Practical implications are discussed. Key words: shaft, design, support interaction, model testing, field measurement, earth pressure, soil displacement.
Seismic-reflection technique used to verify shallow rebound fracture zones in the Pierre Shale of South Dakota
Authors: Nichols Jr. Thomas C. , King Kenneth W. , Collins Donley S. , Williams Robert A.
Published: May 2008

Shallow seismic-reflection data are presented to demonstrate their usefulness for locating and showing the continuity and lateral extent of rebound fracture zones in the Pierre Shale. Rebound fracture zones, identified in boreholes near Hayes, South Dakota, have variable depth, thickness, and character, thus making questionable the correlation of these zones between holes. Thus, the subsequent determination of dip and of continuity of the zones is somewhat tenuous, especially if the fracture characteristics change significantly between holes. Once rebound fracture zones have been identified and located by borehole geotechnical and geologic data, seismic profiles can reveal the extent and geometry of fractures in these zones, thus providing valuable preconstruction information without the cost of additional drilling. Key words: seismic reflection, fracture zones, fracture mapping, shale.
Cyclic behaviour of plate anchors
Authors: Ponniah D. A. , Finlay T. W.
Published: May 2008

This note describes a series of tests carried out on plate anchors embedded in a normally consolidated cohesive soil and subjected to long-term cyclic loads. The principle parameters in the cyclic testing were the mean load and the cyclic amplitude of load about the mean. The tests demonstrated that the anchors did not fail when load cycled up to 50 ± 20% of the drained ultimate pull-out capacity, with the anchor displacements being associated with the buildup and dissipation of pore pressure. With recycling, the level of loading without failure could be increased to 70 ± 20% of the drained capacity. Key words: anchors, cycling, clay.
A GENTLE INTRODUCTION TO S-NET: TYPED STREAM PROCESSING AND DECLARATIVE COORDINATION OF ASYNCHRONOUS COMPONENTS
Authors: GRELCK CLEMENS , SCHOLZ SVEN-BODO , SHAFARENKO ALEX
Published: May 2008

We present the design of S-NET, a coordination language and component technology based on stream processing. S-NET achieves a near-complete separation between application code, written in a conventional programming language, and coordination code, written in S-NET itself. S-NET boxes integrate existing sequential code as stream-processing components into streaming networks, whose construction is based on algebraic formulae built out of four network combinators. Subtyping on the level of boxes and networks and a tailor-made inheritance mechanism achieve flexible software reuse.
ON DESIGN AND APPLICATION MAPPING OF A NETWORK-ON-CHIP(NOC) ARCHITECTURE
Authors: BAHN JUN HO , LEE SEUNG EUN , YANG YOON SEOK , YANG JUNGSOOK , BAGHERZADEH NADER
Published: May 2008

As the number of integrated IP cores in the current System-on-Chips (SoCs) keeps increasing, communication requirements among cores can not be sufficiently satisfied using either traditional or multi-layer bus architectures because of their poor scalability and bandwidth limitation on a single bus. While new interconnection techniques have been explored to overcome such a limitation, the notion of utilizing Network-on-Chip (NoC) technologies for the future generation of high performance and low power chips for myriad of applications, in particular for wireless communication and multimedia processing, has been of great importance. In order for the NoC technologies to succeed, realistic specifications such as throughput, latency, moderate design complexity, programming model, and design tools are necessary requirements. For this purpose, we have covered some of the key and challenging design issues specific to the NoC architecture such as the router design, network interface (NI) issues, and complete system-level modeling. In this paper, we propose a multi-processor system platform adopting NoC techniques, called NePA (Network-based Processor Array). As a component of system platform, the fundamental NoC techniques including the router architecture and generic NI are defined and implemented adopting low power and clock efficient techniques. Using a high-level cycle-accurate simulation, various parameters relevant to its performance and its systematic modeling are extracted and analyzed. By combining various developed systematic models, we construct the tool chain to pursue hardware/software design tradeoffs necessary for better understanding of the NoC techniques. Finally utilizing implementation of parallel FFT algorithms on the homogeneous NePA, the feasibility and advantages of using NoC techniques are shown.
OPERATING SYSTEMS IN SILICON AND THE DYNAMIC MANAGEMENT OF RESOURCES IN MANY-CORE CHIPS
Authors: JESSHOPE CHRIS
Published: May 2008

This discussion paper explores the problems of operating systems support when implementing concurrency controls at the level of the instruction set in processors designed for multi- and many-core chips. It introduces the SVP model and its implementation in DRISC processors to a level of detail required to understand these problems. The major contribution of the paper is in analysing the issues faced in porting operating system functionality onto such processors. The paper covers the issues of job scheduling, dynamic resource management, memory protection and security. It provides examples in μTC (a language based on the SVP model) of how resource management and security issues are managed. It concludes that the implementation of concurrency controls in a processors instruction set is very disruptive. However, the author sees no alternatives if mainstream computing is ever to be served effectively by multi- and many core processors.
Rapid Prototyping of the Data-Driven Chip-Multiprocessor (D2-CMP) using FPGAs
Authors: Tatas Konstantinos , Kyriacou Costas , Evripidou Paraskevas , Trancoso Pedro , Wong Stephan
Published: May 2008

This paper presents the FPGA implementation of the prototype for the Data-Driven Chip-Multiprocessor (D2-CMP). In particular, we study the implementation of a Thread Synchronization Unit (TSU) on FPGA, a hardware unit that enables thread execution using dataflow-like scheduling policy on a chip multiprocessor. Threads are scheduled for execution based on data availability, i.e., a thread is scheduled for execution only if its input data is available. This model of execution is called the non-blocking Data-Driven Multithreading (DDM) model of execution. The DDM model has been evaluated using an execution driven simulator. To validate the simulation results, a 2-node DDM chip multiprocessor has been implemented on a Xilinx Virtex-II Pro FPGA with two PowerPC processors hardwired on the FPGA. Measurements on the hardware prototype show that the TSU can be implemented with a moderate hardware budget. The 2-node multiprocessor has been implemented with less than half of the reconfigurable hardware available on the Xilinx Virtex-II Pro FPGA (45% slices), which corresponds to an ASIC equivalent gate count of 1.9 million gates. Measurements on the prototype showed that the delays incurred by the operation of the TSU can be tolerated.
EXISTENCE OF MULTIPLE POSITIVE SOLUTIONS FOR p-LAPLACIAN PROBLEMS WITH A GENERAL INDEFINITE WEIGHT
Authors: KIM CHAN-GYUN , LEE YONG-HOON
Published: May 2008

This paper studies the existence of positive solutions for a class of singular boundary value problems of p-Laplacian. By using Global Continuation Theorem and the fixed point index technique, criteria of the existence, multiplicity and nonexistence of positive solutions are established.
ASYMPTOTIC CURVES ON SURFACES IN ℝ5
Authors: ROMERO-FUSTER M. C. , RUAS M. A. S. , TARI F.
Published: May 2008

We study asymptotic curves on generically immersed surfaces in ℝ5. We characterize asymptotic directions via the contact of the surface with flat objects (k-planes, k = 1 - 4), give the equation of the asymptotic curves in terms of the coefficients of the second fundamental form and study their generic local configurations.
MULTIPLE BOUND STATES FOR THE SCHRÖDINGER–POISSON PROBLEM
Authors: AMBROSETTI ANTONIO , RUIZ DAVID
Published: May 2008

In this paper, we study the problem [Formula: see text] where u, V : ℝ3 → ℝ are radial functions, λ > 0 and 1 < p < 5. We give multiplicity results, depending on p and on the parameter λ.
ON THE UNIQUENESS OF POSITIVE SOLUTIONS OF A QUASILINEAR EQUATION CONTAINING A WEIGHTED p-LAPLACIAN, THE SUPERLINEAR CASE
Authors: GARCÍA-HUIDOBRO MARTA , HENAO DUVAN A.
Published: May 2008

We consider the quasilinear equation of the form [Formula: see text] where Δpu ≔ div (|∇u|p-2∇u) is the degenerate p-Laplace operator and the weight K is a positive C1function defined in ℝ+. We deal with the case in which f ∈ C[0,∞) has one zero at u0> 0, is non positive and not identically 0 in (0,u0), and is locally Lipschitz, positive and satisfies some superlinear growth assumption in (u0,∞). We carefully study the behavior of the solution of the corresponding initial value problem for the radial version of the quasilinear equation, as well as the behavior of its derivative with respect to the initial value. Combining, as Cortázar, Felmer and Elgueta, comparison arguments due to Coffman and Kwong, with some separation results, we show that any zero of the solutions of the initial value problem is monotone decreasing with respect to the initial value, which leads immediately the uniqueness of positive radial ground states, and the uniqueness of positive radial solutions of the Dirichlet problem on a ball.
EQUIVARIANT COHOMOLOGY AND HOLOMORPHIC INVARIANT
Authors: HOU ZUOLIANG
Published: May 2008

Using equivariant cohomology, we construct a family of holomorphic invariants which include the famous Futaki invariant and its generalization to singular variety as special cases. We are also using this viewpoint to compute the generalized Futaki invariant for complete intersections.
FINITE SPECIAL MOUFANG SETS OF EVEN CHARACTERISTIC
Authors: DE MEDTS TOM , SEGEV YOAV
Published: May 2008

We give a short and elementary proof of the fact that a finite special Moufang set with root groups of even order is isomorphic to the unique Moufang set whose little projective group is PSL 2(2k) for some integer k ≥ 1.
FINITE SPECIAL MOUFANG SETS OF ODD CHARACTERISTIC
Authors: SEGEV YOAV
Published: May 2008

In this paper we classify finite special Moufang sets 𝕄(U,τ) of odd characteristic. The characteristic 2 case was handled in another paper by De Medts and the author (see [3]). We prove that U is elementary abelian. Then, we show that 𝕄(U,τ) is the unique Moufang set whose little projective group is PSL 2(|U|). The emphasis of this paper is on obtaining elementary proofs. Section 3 deals with root subgroups in any Moufang set and may be of independent interest.