bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of talc dust on respiratory health: results of a longitudinal survey of 378 French and Austrian talc workers
Authors: Wild P , Leodolter K , Réfrégier M , Schmidt H , Bourgkard E
Published: October 2007

Objectives:

The aim of this longitudinal study was to investigate the effects on respiratory health of talc dust, free of asbestiform fibres, at or below airborne concentrations of 2 mg/m3.

Methods:

The respiratory health and dust exposure of all workers with at least 5 years of employment at two talc producing facilities in France and Austria were surveyed between 1988 and 2003. Standard forced expiratory volumes and standard chestxrays were obtained on repeated occasions and recorded using strict quality control procedures. Of a target population of 430 subjects, 378 (88%) were examined at least twice. A quantitative exposure matrix was set up based on 4602 personal exposure measurements of respirable dust and qualitative descriptions of the industrial processes and individual protection devices.

Results:

The mean duration of follow-up was 14.5 years with a mean estimated talc dust concentration during follow-up of 1.46 mg/m3. The prevalence of small radiological opacities and lung function parameters were significantly related to cumulative exposure at inclusion but not to exposure during the study period. Overall, the forced expiratory volume in 1 s decreased by 66 ml per 100 years.mg/m3, which is less than that reported for other types of mineral dusts.

Conclusions:

Although early exposure levels to talc as assessed at inclusion were associated with decreased lung function and an increased prevalence of small radiological opacities, there was no evidence of detrimental effects of talc exposure, as assessed within the study period, on lung function and small radiological opacities.
Biomechanical strains and low back disorders: quantifying the effects of the number of years of exposure on various types of pain
Authors: Plouvier S , Renahy E , Chastang J F , Bonenfant S , Leclerc A
Published: October 2007

Objective:

To assess the effects of duration of exposure to biomechanical strains on various types of low back pain (LBP).

Methods:

The population study was a random sample from the GAZEL cohort. Durations of exposure to selected biomechanical strains during subjects’ working lifetime and potential confounders were assessed in 1996 by self-administered questionnaires. Data on LBP in the previous 12 months were collected in 2001. Relations between various dimensions of LBP and durations of exposure to the biomechanical strains were analysed with multivariate regression models. Polytomous models were built to determine whether some biomechanical strains were specifically associated with some types of LBP.

Results:

Analyses were performed separately for men (n = 2218) and women (n = 383). Significant associations were observed (ORs reported are those for 20 years of exposure) between LBP and durations of driving and bending/twisting for men (OR 1.24 and 1.37 respectively); LBP for more than 30 days and duration of exposure to bending/twisting for men and women (OR 2.20 and 2.00 respectively) and duration of driving for women (OR 3.15); LBP radiating to the leg and duration of driving for men (OR 1.43) and bending/twisting for women (OR 1.95); LBP radiating below the knee and duration of exposure to pulling/pushing/carrying for men (OR 1.88). Bending/twisting in both men and women, and driving for women appeared to be stronger risk factors for LBP for more than 30 days. Pulling/pushing/carrying heavy loads appeared to be a risk factor specific for LBP radiating below the knee for men.

Conclusion:

This study suggests that exposure to biomechanical strains has long-term effects and a dose-response relation with duration of exposure and specific effects for some types of LBP.
A description of the methods used to obtain information on ancient disease and medicine and of how the evidence has survived
Authors: Metcalfe Neil H
Published: October 2007

This paper summarises the common modalities that are available for researching ancient medicine and disease as well as explaining how some of these sources have survived to modern day. These are explained under the three broad headings of palaeopathology, artefacts, and texts. The descriptions use a variety of examples from ancient societies including in the Bronze Age, Babylonia and Assyria, ancient Egypt, ancient Greece, and ancient Rome to help explain these modalities. In addition, a review of the advantages and disadvantages of using these tools is included to help current and future historians in stimulating future research in this fascinating area.
“Please, I want to go home”: ethical issues raised when considering choice of place of care in palliative care
Authors: Wheatley Victoria J , Baker J Idris
Published: October 2007

Many palliative care patients would prefer to receive care, and to die, at home. Despite this many die in institutions. In response to this, politicians and charities have adopted policies aimed at increasing the opportunities for care and death at home. The need to discuss plans for discharge with most inpatients reinforces expectations of a choice of place of care. However, many palliative patients do not have a choice of care at home. This article will explore the circumstances in which patients are unable to choose home care and consider changes in clinical practice that can help to maximise choice. We shall argue that there is a distinction between the preferences of patients and the choices actually available to them. In attempting to make this distinction we advocate consideration of the balance between the ethical principles relevant to each case.
Current management of male-to-female gender identity disorder in the UK
Authors: Tugnet Nicola , Goddard Jonathan Charles , Vickery Richard M , Khoosal Deenesh , Terry Tim R
Published: October 2007

Gender identity disorder (GID), or transsexualism as it is more commonly known, is a highly complex clinical entity. Although the exact aetiology of GID is unknown, several environmental, genetic and anatomical theories have been described. The diagnosis of GID can be a difficult process but is established currently using standards of care as defined by the Harry Benjamin International Gender Dysphoria Association. Patients go through extensive psychiatric assessment, including the Real Life Experience, which entails living in the desired gender role 24 h a day for a minimum period of 12 months. The majority of GID patients will eventually go on to have gender realignment surgery, which includes feminising genitoplasty. The clinical features, diagnostic approach and management of male-to-female GID in the UK are reviewed, including the behavioural, psychological and surgical aspects.
Sarcoid heart disease
Authors: Dubrey Simon W , Bell Alex , Mittal Tarun K
Published: October 2007

To this day the aetiology of sarcoidosis continues to elude definition. Partially as a consequence of this, little in the way of new therapies has evolved. The enigma of this condition is that, unusually for a disease with the potential for devastating consequences, many patients show spontaneous resolution and recover. Cardiac involvement can affect individuals of any age, gender or race and has a predilection for the conduction system of the heart. Heart involvement can also cause a dilated cardiomyopathy with consequent progressive heart failure. The most common presentation of this systemic disease is with pulmonary infiltration, but many cases will be asymptomatic and are detected on routine chest radiography revealing lymphadenopathy. Current advances lie in the newer methods of imaging and diagnosing this unusual heart disease. This review describes the pathology and diagnosis of this condition and the newer imaging techniques that have developed for determining cardiac involvement.
Herbal medicine: buy one, get two free
Authors: Ernst E
Published: October 2007

In recent years, herbal medicine seems to have gone from strength to strength. However, not one but three types of herbal medicine exist—and we are confusing them at our peril.
“Accommodating” smoke-free policies: tobacco industry’s Courtesy of Choice programme in Latin America
Authors: Sebrié Ernesto M , Glantz Stanton A
Published: October 2007

Objective:To understand the implementation and effects of the Courtesy of Choice programme designed to “accommodate” smokers as an alternative to smoke-free polices developed by Philip Morris International (PMI) and supported by RJ Reynolds (RJR) and British American Tobacco (BAT) since the mid-1990s in Latin America.

Methods:Analysis of internal tobacco industry documents, BAT “social reports”, news reports and tobacco control legislation.

Results:Since the mid-1990s, PMI, BAT and RJR promoted Accommodation Programs to maintain the social acceptability of smoking. As in other parts of the world, multinational tobacco companies partnered with third party allies from the hospitality industry in Latin America. The campaign was extended from the hospitality industry (bars, restaurants and hotels) to other venues such as workplaces and airport lounges. A local public relations agency, as well as a network of engineers and other experts in ventilation systems, was hired to promote the tobacco industry’s programme. The most important outcome of these campaigns in several countries was the prevention of meaningful smoke-free policies, both in public places and in workplaces.

Conclusions:Courtesy of Choice remains an effective public relations campaign to undermine smoke-free policies in Latin America. The tobacco companies’ accommodation campaign undermines the implementation of measures to protect people from second-hand smoke called for by the World Health Organization Framework Convention on Tobacco Control, perpetuating the exposure to tobacco smoke in indoor enclosed environments.
Smoking too few cigarettes to be at risk? Smokers’ perceptions of risk and risk denial, a French survey
Authors: Peretti-Watel Patrick , Constance Jean , Guilbert Philippe , Gautier Arnaud , Beck François , Moatti Jean-Paul
Published: October 2007

Background:Past studies on smokers’ risk perception have produced mixed results. We endorsed a new approach to assess smokers’ perceptions of risk by asking them to estimate threshold values for the cancer risk associated with daily consumption of tobacco and number of smoking years. We expected that many smokers would endorse a “risk denial” attitude, with threshold estimates higher than their own smoking consumption and duration.

Methodology:A French national telephone survey (n = 3820; 979 current smokers) included several questions about smoking behaviours and related beliefs.

Results:Among current smokers, 44% considered that smoking can cause cancer only for a daily consumption higher than their own consumption, and an additional 20% considered that the cancer risk becomes high only for a smoking duration higher than their own. Most smokers also agreed with other “risk denial” statements (“smoking is not more dangerous than air pollution,” “some people smoke their whole life but never get sick”). Those who considered they smoked too few cigarettes to be at risk were less likely to report personal fear of smoking related cancer.

Conclusion:Risk denial is quite widespread among smokers and does not simply reflect a lack of information about health risks related to tobacco. Fully informing smokers about their risks may necessitate changing the way they process information to produce beliefs and limiting their capacity to generate self exempting beliefs.
Protection from experimental ventilator-induced acute lung injury by IL-1 receptor blockade
Authors: Frank James A , Pittet Jean-Francois , Wray Charlie , Matthay Michael A.
Published: October 2007

Background: Clinical studies have shown that injurious mechanical ventilation is associated with elevated airspace and plasma levels of interleukin-1β (IL-1β); however, the potential therapeutic value of IL-1 inhibition in acute lung injury has not been thoroughly investigated.

A study was undertaken to determine if IL-1 signaling is a necessary early event in the pathogenesis of experimental ventilator-induced lung injury (VILI).

Methods: Mice deficient in IL-1 receptor type 1 (IL1R1) and rats treated with IL-1 receptor antagonist (IL-1Ra) were mechanically ventilated with high tidal volume (30 ml/kg) and the effect of IL-1 signaling blockade on lung injury severity was determined.

Results: Permeability as measured by radiolabeled albumin flux was significantly lower in IL1R1 null mice compared with wild type mice during injurious ventilation (P<0.05). IL-1Ra significantly decreased protein permeability and pulmonary oedema in rats during injurious ventilation. IL-1Ra also decreased airspace and plasma levels of the chemokine CXCL1 and airspace neutrophils. IL-1Ra decreased expression of NOS2 and ICAM-1 mRNA in whole lung. Bronchoalveolar lavage fluid levels of RTI40, a marker of type I cell injury, were 2.5 times lower in following IL-1Ra treatment (P < 0.05). In isolated type II pneumocytes, IL-1β reduced electrical resistance and increased transepithelial permeability.

Conclusions: IL-1 contributes to alveolar barrier dysfunction in VILI by promoting lung neutrophil recruitment, and by increasing epithelial injury and permeability. Because preserved alveolar barrier function is associated with better outcomes in patients with acute lung injury, these data support further testing of IL-1Ra for the treatment of acute lung injury.
Observations sur une méthode de dosage de la proline libre dans les extraits de plantes
Authors: Paquin Roger , Lechasseur Pierre
Published: October 2007

Folin-type resins used to purify plant extracts of basic amino acids that interfere with proline determination are not selective and partially retain this amino acid and the basic amino acids. Therefore, their use should be avoided, otherwise correction factors must be introduced. Modifications to another method allow a more rapid and precise estimation of proline.
The ultrastructure of nuclear division in Armillaria mellea: meiosis
Authors: Peabody Diane Cope , Motta Jerome J.
Published: October 2007

Meiosis I in isolates of Armillaria mellea in which subhymenial hyphae are uninucleate and lack clamp connections was examined ultrastructurally. Although the overall pattern of development and basidiosporogenesis appears similar to other Homobasidiomycetes it was observed that spindle pole bodies are predominantly monoglobular and are associated with a unique membrane structure of the subtending nuclear envelope. The nuclear envelope also disappears at metaphase I and reforms by the coalescence of membrane fragments around the compacted chromatin at late telophase I. The significance of these features in relation to other Basidiomycetes is briefly discussed.
Natural variation in morphology among diverse populations of yellow birch (Betula alleghaniensis) and sweet birch (B. lenta)
Authors: Sharik Terry L. , Barnes Burton V.
Published: October 2007

Natural variation was studied in 47 morphological attributes of yellow birch and sweet birch collected from adult trees along five elevational transects in the Appalachian Mountains. Populations of one or both species were analyzed from 30 locales extending from southern North Carolina to northern Vermont and New Hampshire. The major objectives of the study were (1) to test for differences in foliage, fruits, bark, and pollen among species and among populations; (2) to determine if patterns of variation associated with latitude could be strengthened by elevational adjustments; and (3) to determine the degree of similarity in patterns of variation for the two species.The results indicated considerable within-population variation and significant differences among populations and species. However, few morphological characters showed consistent trends in size, shape, or pubescence with changes in elevation and latitude. Where relationships were consistent, they were not particularly strong as indicated by linear correlation coefficients (few exceed 0.70). These findings are in contrast to earlier studies demonstrating a strong relationship of growth periodicity to elevation and latitude of seedling populations grown in a uniform garden.Preliminary evidence suggests that expression of morphological variation may be greater in the less extreme portions of the species latitudinal and elevational distributions.
Effect of sulphur dioxide and ozone singly or in combination on leaf chlorophyll, RNA, and protein in white bean
Authors: Beckerson D. W. , Hofstra G.
Published: October 2007

The effect of 0.15 ppm ozone and (or) 0.15 ppm sulphurdioxide on leaf chlorophyll, RNA, and protein levels was investigated. Ozone-treated leaves exhibited reddish-brown colored lesions and an immediate and continuous decrease in chlorophyll a and b levels over a 5-day period, whereas protein levels increased and there was no effect on RNA levels compared to the control group of plants. Sulphur dioxide-treated leaves exhibited an immediate increase in chlorophyll a and b, but protein and RNA levels were not affected. The sulphur dioxide – ozone mixture caused an interveinal chlorisis by about day 3 and produced a decrease in chlorophyll a and b which was delayed by 2 days compared with leaves exposed to ozone alone. By the end of the 5-day period, chlorophyll a and b levels were less than in leaves treated with ozone alone, but the interveinal chlorosis that occurred was not due to phaeophytinization of the chlorophyll molecules. Protein and RNA levels were not affected. Although both ozone and the pollutant mixture caused chlorophyll destruction and premature leaf drop, the changes that occurred in the leaf were not typical of normal leaf senescence.
Glacier fluctuations during the past millennium in Garibaldi Provincial Park, southern Coast Mountains, British Columbia
Authors: Koch Johannes , Clague John J , Osborn Gerald D
Published: October 2007

The Little Ice Age glacier history in Garibaldi Provincial Park (southern Coast Mountains, British Columbia) was reconstructed using geomorphic mapping, radiocarbon ages on fossil wood in glacier forefields, dendrochronology, and lichenometry. The Little Ice Age began in the 11th century. Glaciers reached their first maximum of the past millennium in the 12th century. They were only slightly more extensive than today in the 13th century, but advanced at least twice in the 14th and 15th centuries to near their maximum Little Ice Age positions. Glaciers probably fluctuated around these advanced positions from the 15th century to the beginning of the 18th century. They achieved their greatest extent between A.D. 1690 and 1720. Moraines were deposited at positions beyond present-day ice limits throughout the 19th and early 20th centuries. Glacier fluctuations appear to be synchronous throughout Garibaldi Park. This chronology agrees well with similar records from other mountain ranges and with reconstructed Northern Hemisphere temperature series, indicating global forcing of glacier fluctuations in the past millennium. It also corresponds with sunspot minima, indicating that solar irradiance plays an important role in late Holocene climate change.
Rifting of a Mississippian continental arc system: Little Salmon formation, Yukon–Tanana terrane, northern Canadian Cordillera
Authors: Simard Renée-Luce , Dostal Jaroslav , Colpron Maurice
Published: October 2007

The Yukon–Tanana terrane in the northern Canadian Cordillera records the development of a series of mid- to late Paleozoic arc systems, punctuated by intra-arc deformation, uplift, and episodic rifting coeval with back-arc extension, built upon a metasedimentary basement of northwestern Laurentian affinity. In central Yukon, the Little Kalzas formation records the development of one of these Mississippian continental arcs, whereas the Little Salmon formation records the development of an intra-arc rift basin within a continental arc. The Little Salmon formation lower succession comprises mainly volcaniclastic rocks derived from erosion of Early Mississippian and older units, including rocks of the Little Kalzas continental arc. Above a medial limestone member, the upper succession of the Little Salmon formation includes alkali basalt, breccia, and crystal and ash tuffs in the north and predominantly epiclastic rocks interbedded with crystal and ash tuffs in the south. The alkali basalts have the geochemical characteristics of ocean-island basalts and their positive ε Nd 340 (+7.3) and low 87Sr/86Sr values (0.705) suggest a primitive magma source with little or no involvement of continental crust. The transition between the northern and southern facies of the upper succession of the Little Salmon formation coincides with a northeast-trending synvolcanic fault inferred to have controlled alkali basalt eruptions and deposition of Mn-bearing exhalite in the north and basin plain sedimentation in the south. The environment of deposition of the Little Salmon formation resembles that of the modern Sumisu rift in the Izu–Bonin–Mariana arc system or the early stages of development of the Japan island-arc system.
The Late Ordovician Dawson Point Formation (Timiskaming outlier, Ontario): key to a new regional synthesis of Richmondian–Hirnantian carbonate and siliciclastic magnafacies across the central Canadian craton
Authors: Dix George R , Coniglio Mario , Riva John FV , Achab Aïcha
Published: October 2007

Current paleogeographic reconstructions extend Late Ordovician Taconic-derived siliciclastics across the central Canadian craton prior to the terminal Ordovician glacioeustatic lowstand. Revision of the Late Ordovician Dawson Point Formation of the Timiskaming outlier greatly reduces the distribution of these siliciclastics, and documents a greater spread of shallow-water carbonate of Richmondian age. As revised, the Dawson Point Formation contains two informal members: a deep-water graptolitic shale that grades upward into shallow-water siliciclastic redbeds, and an upper member of shallow-water, muddy, crinoidal limestone with interbedded shale, likely representing low-energy shoals on a muddy shelf. Deep-water shale accumulation began in the upper manitoulinensis graptolite Zone following foundering of the regional foreland carbonate platform. Basin development documents a northward-younging (~1 million years) from southern Ontario foreland basins, in keeping with regional tectonic-driven transgression along eastern North America. The shale-to-carbonate succession of the Dawson Point Formation correlates with the Georgian Bay Formation on Manitoulin Island, wherein the upper carbonate-dominated divisions of both formations are equivalent to the siliciclastic Queenston Formation of southern Ontario. In absence of additional biostratigraphic information, the upper member of the Dawson Point Formation is likely Richmondian (or late Ashgillian) in age. The revised Late Ordovician history of the Timiskaming outlier may identify a once significant volume of shallow-water carbonate across the central Canadian craton, with related sequestration of carbon dioxide possibly aiding global cooling. Erosion of the carbonate, driven by developing glacioeustatic lowstand conditions, was likely contemporaneous with early Hirnantian peritidal deposition of the uppermost Queenston Formation in southern Ontario.
Predicting the invasion success of an introduced omnivore in a large, heterogeneous reservoir
Authors: Vatland Shane , Budy Phaedra
Published: October 2007

We demonstrate that invasion success, through the introduction and establishment stages, can generally be predicted based on biological characteristics of the organisms and physical aspects of the environment; however, predicting subsequent effects during integration is more challenging, especially for omnivorous fish species in large, heterogeneous systems. When gizzard shad (Dorosoma cepedianum) were incidentally introduced into Lake Powell, Utah–Arizona (2000), we predicted they would be successful invaders and would have food-web effects ranging from neutral to negative. As predicted, gizzard shad successfully established and dispersed throughout this large reservoir (300 km) within just 4 years, and their density was positively correlated with productivity. Also as predicted, gizzard shad exhibited fast growth rates, and striped bass (Morone saxatilis) predators were thus gape-limited, obtaining little gizzard shad forage. Contrary to our predictions, however, competition over zooplankton resources between gizzard shad and both threadfin shad (Dorosoma petenense) and juvenile striped bass appeared limited because of spatial segregation and diet preference. In sum, gizzard shad will continue to be successful invaders, but with limited effects on the established predator–prey cycle.
Can the precision of bottom trawl indices be increased by using simultaneously collected acoustic data? The Barents Sea experience
Authors: Hjellvik Vidar , Tjøstheim Dag , Godø Olav Rune
Published: October 2007

Acoustic data are recorded continuously during the winter survey for demersal fish in the Barents Sea. This paper presents a method for using the information from the acoustic recordings between trawl stations in an attempt to increase the precision of the trawl estimate. The method is related to the double-sampling regression estimation, in which information from a frequently sampled auxiliary variable (e.g., acoustics) that is correlated with the main variable (e.g., trawl) is used for the purpose of increasing the precision in the estimate of the population mean of the main variable. The version presented here allows for additional explanatory variables and for autocorrelation in the main and auxiliary variables. However, when applied to the Barents Sea data, only a minor variance reduction is obtained. The main reasons for this are a high autocorrelation in the acoustic data and a relatively low correlation between trawl and acoustics on trawl stations. Another unexpected result is that the acoustic density during trawling is significantly higher than between trawl stations.
Historical analysis ofPanI in Atlantic cod (Gadus morhua): temporal stability of allele frequencies in the southeastern part of the species distribution
Authors: Nielsen Einar Eg , MacKenzie Brian R , Magnussen Eydfinn , Meldrup Dorte
Published: October 2007

We investigated temporal genetic differentiation at the pantophysin (Pan I) locus in four Atlantic cod (Gadus morhua) populations from the southeastern part of the species distribution: the Baltic Sea, the North Sea, the Faroe Plateau, and the Faroe Bank. Historical otolith collections enabled investigation of allele frequency variation over time periods up to 69 years employing Pan I primers specifically designed for partially degraded DNA. Small and nonsignificant temporal changes in Pan I allele frequencies were observed in the four populations. Simultaneous microsatellite analysis revealed similar temporal genetic stability with temporal FSTvalues ranging from 0 to 0.006, suggesting limited demographic changes. Sea surface temperature, which has been suggested as the primary driver for the geographical distribution of Pan I alleles in cod, showed no long-term trend although temperature has increased since the mid-1990s. Our study demonstrates that populations in the southeastern part of the species range has been characterized by very high frequencies of the Pan IAallele for many decades, and accordingly, Pan I serves as a reliable marker for genetic stock identification on a macrogeographical scale.
Physiological consequences of “premature freshwater return” for wild sea-run brown trout (Salmo trutta) postsmolts infested with sea lice (Lepeophtheirus salmonis)
Authors: Wells Alan , Grierson Christal E , Marshall Laura , MacKenzie Monique , Russon Iain J , Reinardy Helena , Sivertsgård Rolf , Bjørn Pål A , Finstad Bengt , Wendelaar Bonga Sjoerd E , Todd Christopher D , Hazon Neil
Published: October 2007

The physiological consequences of premature migratory return to freshwater for wild sea-run brown trout (Salmo trutta) smolts infested with sea lice (Lepeophtheirus salmonis) were investigated in the laboratory. Osmoregulatory, metabolic, and stress markers were analysed in order to assess the potential consequences of transfer to freshwater, 19 days after the challenge with L. salmonis. Infestation intensity was significantly reduced following transfer to freshwater, and mortality rates were markedly higher in infested fish maintained in seawater vs. fish that were transferred to freshwater. Significant sea lice effects, consistent across a number of physiological markers, were apparent once L. salmonis developed to the mobile stages. Plasma chloride, lactate, and cortisol all were significantly higher than control values, and liver glycogen concentration was significantly reduced in infested fish in seawater. After return to freshwater, these physiological measures returned to control levels, but significant lice effects persisted for fish maintained in seawater. Premature return of infested sea-run brown trout to freshwater does, therefore, confer significant short-term physiological benefits across a range of osmoregulatory, metabolic, and stress markers.
Influence of velocity and chlorophyll standing stock on periphyton δ13C and δ15N in the Ste. Marguerite River system, Quebec
Authors: Rasmussen Joseph B , Trudeau Veronique
Published: October 2007

In a previous laboratory experiment, water velocity had a strong negative effect on periphyton δ13C and δ15N, probably reflecting the effect of flow on boundary-layer exchange. To determine whether similar patterns could be detected in situ at different spatial scales, we examined several reaches, each with a wide range in water velocity and chlorophyll standing stock. Periphyton samples were uniform in composition, composed predominantly of living and dead diatoms of very few species. δ13C signatures were more variable (–17.7 to –31.5) than δ15N signatures (–0.4 to 5.7). Velocity and chlorophyll were significant predictors of periphyton δ13C within reaches, mainly at medium scales (10–500 m) where persistent alternations between fast and slow current (riffles–runs–pools) produced inverse fluctuations of periphyton δ13C. However, none of the variability in δ15N could be explained, possibly a result of severe boundary-layer N depletion. Similarly, the velocity and chlorophyll predictors could not explain the among-reach signature differences for either isotope. δ13C signatures tended to be13C-depleted in the tributary streams and13C-enriched in the downstream reaches.
Numerical changes in stream-resident brown trout (Salmo trutta): uncovering the roles of density-dependent and density-independent factors across space and time
Authors: Lobón-Cerviá Javier
Published: October 2007

The objective was to uncover the roles of environmental, density-independent, and intrinsic, density-dependent factors as drivers of population size in stream-resident brown trout (Salmo trutta) across space and time. The study was based on census data and environmental variables collected every fourth month over 1986–2006 at 12 sites selected along four Rio Esva tributaries (northwestern Spain). Density-dependent hypotheses involving the operation of current and lagged densities on recruitment and subsequent spawner density were analyzed at three increasingly larger geographical scales (site, stream, and river drainage). No evidence supported these hypotheses, suggesting an overall lack of negative feedbacks among year classes. Stream discharge in March when trout emerge and site depth explained substantial amounts of spatiotemporal variation in recruitment. The effects of these two factors on recruitment were sufficiently strong to be detected in year-class mortality and subsequent spawner density. Discharge and site depth determine the amount of spatial habitat suitable for sized individuals during their lifetime and, hence, the maximum number of individuals across space and time. Recruitment dependence, as a delayed density-dependent factor, adjusts the numbers in excess to the numbers established by spatial habitat. These findings differ markedly from the prediction of the most recent theories of population dynamics and are discussed in this context.
Explicit consideration of uncertainty in Great Lakes fisheries management: decision analysis of sea lamprey (Petromyzon marinus) control in the St. Marys River
Authors: Haeseker Steven L , Jones Michael L , Peterman Randall M , Bence James R , Dai Wenjing , Christie Gavin C
Published: October 2007

We used decision analysis to assist the Great Lakes Fishery Commission (GLFC) with sea lamprey (Petromyzon marinus) control in the St. Marys River, which connects Lake Superior to Lake Huron and until recently has been a major source of sea lamprey infestation of Lake Huron. The process involved decision-makers, managers, and experts in an analysis of management options, objectives, and critical uncertainties affecting the expected performance of alternative choices. We developed quantitative assessments of uncertainty about sea lamprey demographics and about the implementation effectiveness of three pest control options: trapping adult lampreys, sterile male releases, and lampricide treatment. We used a stochastic simulation model to forecast future parasitic sea lamprey abundance in Lake Huron for 10 management options. Management options that included enhanced levels of trapping and sterile male releases exhibited the best performance for all measures. Our analysis substantially influenced the GLFC strategy for the St. Marys River, providing an example of how explicit consideration of uncertainty using decision analysis can influence fishery management decisions.
PRODUCTION OF FEMTOSECOND PULSES AND MICRON BEAM SPOTS FOR HIGH BRIGHTNESS ELECTRON BEAM APPLICATIONS
Authors: ANDERSON S. G. , GIBSON D. J. , HARTEMANN F. V. , JACOB J. S. , TREMAINE A. M. , LIM J. K. , FRIGOLA P. , ROSENZWEIG J. B. , TRAVISH G.
Published: October 2007

Current and future applications of high brightness electron beams, which include advanced accelerators and beam-radiation interactions require both transverse and longitudinal beam sizes on the order of tens of microns. Ultra-high density beams may be produced at moderate energy (50 MeV) by compression and subsequent strong focusing of low emittance, photoinjector sources. We describe the implementation of this method used at the PLEIADES inverse-Compton scattering (ICS) x-ray source at LLNL in which the photoinjector-generated beam has been compressed to 300 fsec rms duration using the velocity bunching technique and focused to 20 μm rms size using an extremely high gradient, permanent magnet quadrupole focusing system.
WAKEFIELDS OF SUB-PICOSECOND ELECTRON BUNCHES
Authors: BANE K. L. F.
Published: October 2007

We discuss wakefields excited by short bunches in accelerators. In particular, we review some of what has been learned in recent years concerning diffraction wakes, roughness impedance, coherent synchrotron radiation wakes, and the resistive wall wake, focusing on analytical solutions where possible. As examples, we apply formulas for these wakes to various parts of the Linac Coherent Light Source (LCLS) project. The longitudinal accelerator structure wake of the SLAC linac is an important ingredient in the LCLS bunch compression process. Of the wakes in the undulator region, the dominant one is the resistive wall wake of the beam pipe.
NEEDLE CATHODES FOR HIGH-BRIGHTNESS BEAMS
Authors: BOULWARE C. H. , JARVIS J. D. , ANDREWS H. L. , BRAU C. A.
Published: October 2007

At the tips of sharp needles, the surface electric field is enhanced by many orders of magnitude. This intensifies thermionic emission and photoemission of electrons through the Schottky effect, and reduces the effect of space charge. The increased current density improves the brightness of electron sources by orders of magnitude. In addition, at very high fields (>109 V/m ), field emission and photo-field emission produce very high current density. Arrays of needles can be used to achieve high total current.
SCALED MODELS: SPACE-CHARGE DOMINATED ELECTRON STORAGE RINGS
Authors: KISHEK R. A. , BAI G. , BERNAL S. , FELDMAN D. , GODLOVE T. F. , HABER I. , O'SHEA P. G. , QUINN B. , PAPADOPOULOS C. , REISER M. , STRATAKIS D. , TIAN K. , TOBIN C. J. , WALTER M.
Published: October 2007

New coherent radiation sources in the hard X-ray and Terahertz regimes promise exciting new developments in science, as previously dark areas of the spectrum are brightly illuminated. Ultra-short, ultra-bright radiation packets can probe the structure of matter, and image chemical and biological processes well beyond the present state of the art. Production of this coherent radiation, however, places an unprecedented challenge on the production and acceleration of high-quality electron beams. To deliver a nano-Coulomb of charge with an emittance of less than one micron, while transporting the beam through long sections of acceleration and compression, is the prerequisite for unlocking the gates of this promising new science. Using a low-energy electron storage ring, we deliberately enhance the space charge force while slowing down the time-scale to easily measurable levels so as to maximize our understanding of the particle dynamics necessary for producing bright beams.
MAXIMIZING BRIGHTNESS IN PHOTOINJECTORS
Authors: LIMBORG-DEPREY C. , TOMIZAWA H.
Published: October 2007

If the laser pulse driving photoinjectors could be arbitrarily shaped, the emittance growth induced by space charge effects could be totally compensated for. In particular, for RF guns, the photo-electron distribution leaving the cathode should be close to a uniform distribution contained in a 3D-ellipsoid contour. For photo-cathodes which have very fast emission times, and assuming a perfectly uniform emitting surface, this could be achieved by shaping the laser in a pulse of constant fluence and limited in space by a 3D-ellipsoid contour. Simulations show that in such conditions, with the standard linear emittance compensation, the emittance at the end of the photo-injector beamline approaches the minimum value imposed by the cathode emittance. Brightness, which is expressed as the ratio of peak current over the product of the two transverse emittance, seems to be maximized for small charges. Numerical simulations also show that for very high charge per bunch (10nC), emittances as small as 2 mm-mrad could be reached by using 3D-ellipsoidal laser pulses in an S-Band gun. The production of 3D-ellipsoidal pulses is very challenging, but seems worthwhile the effort. We briefly discuss some of the present ideas and difficulties of achieving such pulses.
SCALING LAWS OF STRUCTURE-BASED OPTICAL ACCELERATORS
Authors: MIZRAHI AMIT , KARAGODSKY VADIM , SCHÄCHTER LEVI
Published: October 2007

A structure-based laser accelerator harnesses technological progress developed by the laser and optical fiber industries, potentially facilitating a compact and efficient system. In the optical regime, dielectrics sustain higher electric fields and gradients of the order of a few GV/m may become available, but the acceleration structures are different than those used in the microwave regime. Various dielectric structures have been analyzed, and from the pure accelerator parameters perspective (gradient, interaction impedance, group velocity, wake-fields), their performance is of great promise. Operation similar to current linear accelerators may lead to a prohibitively low efficiency. Therefore, including a feedback attached to each module may improve the efficiency from a few percents to higher than 90% – in fact, the efficiency is limited only by the constraints on the stability of the optical system. Single mode operation in the optical regime imposes that at least one of the dimensions of each micro-bunch ought to be sub-micronic leading to a stringent constraint on the emittance and thus on the luminosity. Attempting to increase the latter, imposes high energy density in the vacuum tunnel as well as in its adjacent dielectric layer(s). This, in turn, is bounded by the maximum stress, temperature increase and heat dissipation, dielectrics can sustain at these scales.
ON THE ROLE OF INTERPRETABILITY IN FUZZY DATA MINING
Authors: MENCAR CORRADO , CASTELLANO GIOVANNA , FANELLI ANNA M.
Published: October 2007

Data Mining, a central step in the broader overall process of Knowledge Discovery from Databases, concerns with discovering useful properties, called patterns, from data. Understandability is an essential — yet rarely tackled — feature that makes resulting patterns accessible by end users. In this paper we argue that the adoption of Fuzzy Logic for Data Mining can improve understandability of derived patterns. Indeed, Fuzzy Logic is able to represent concepts in a “human-centric” way. Hence, Data Mining methods based on Fuzzy Logic may potentially meet the so-called “Comprehensibility Postulate”, which characterizes the blurry notion of understandability. However, the mere adoption of Fuzzy Logic for Data Mining is not enough to achieve understandability. This paper describes and comments a number of issues that need to be addressed to provide for understandable patterns. A careful consideration of all such issues may end up in a systematic methodology to discover comprehensible knowledge from data.
RESAMPLING FOR FUZZY CLUSTERING
Authors: BORGELT CHRISTIAN
Published: October 2007

Resampling methods are among the best approaches to determine the number of clusters in prototype-based clustering. The core idea is that with the right choice for the number of clusters basically the same cluster structures should be obtained from subsamples of the given data set, while a wrong choice should produce considerably varying cluster structures. In this paper I give an overview how such resampling approaches can be transferred to fuzzy and probabilistic clustering. I study several cluster comparison measures, which can be parameterized with t-norms, and report experiments that provide some guidance which of them may be the best choice.
VISUALIZATION OF FUZZY CLASSIFIERS
Authors: REHM FRANK , KLAWONN FRANK , KRUSE RUDOLF
Published: October 2007

This paper presents different techniques to visualize high-dimensional fuzzy rule bases in relation to the classified data. The degree of membership to influential rules can be visualized for an entire data set. This enables the observer to detect conflicting or error-prone rules as well as misclassified feature vectors. Results are shown on a benchmark data set and on a weather data set that is used to predict flight durations on a major European airport.
INTERVAL METHODS IN KNOWLEDGE REPRESENTATION
Authors: Kreinovich Vladik
Published: October 2007

This section is maintained by Vladik Kreinovich. Please send your abstracts (or copies of papers that you want to see reviewed here) to vladik@utep.edu, or by regular mail to: V. Kreinovich, Department of Computer Science, University of Texas, El Paso, TX 79968, USA.
Discrete Plio-Pleistocene phases of tilting and counterclockwise rotation in the southeastern Aegean arc (Rhodos, Greece): early Pliocene formation of the south Aegean left-lateral strike-slip system
Authors: van Hinsbergen Douwe J.J. , Krijgsman Wout , Langereis Cor G. , Cornée Jean-Jacques , Duermeijer Charon E. , van Vugt Nicole
Published: October 2007

The island of Rhodos represents an uplifted block in the largely submerged southeastern Aegean forearc. It has a complex history of subsidence, uplift and counterclockwise rotation during the Plio-Pleistocene, in response to the interplay between large-scale geodynamic processes. In this paper, we present a new chronostratigraphic framework for the continental Pliocene Apolakkia basin of southwestern Rhodos. We combine these time constraints with recently published chronostratigraphic data from the marine Plio-Pleistocene basins of northeastern Rhodos to reconstruct rotational and vertical motions. Our palaeomagnetic results identify two rotation phases for Rhodos:
c
. 10° (9 ± 6°) counterclockwise (ccw) rotation between 3.8 and 3.6 Ma, and
c
. 17 ± 6° ccw rotation since 0.8 Ma. Between these phases, Rhodos tilted to the SE, drowning the southeastern coast to a depth of 500–600 m between 2.5 and 1.8 Ma, then to the NW, which resulted in the re-emergence of the drowned relief between 1.5 and 1.1 Ma. We relate the rotations of Rhodos to incipient formation of the south Aegean sinistral strike-slip system and the foundering of the Rhodos basin. The previously shown absence of Messinian evaporites in the deep-marine Rhodos basin in combination with the 3.8 Ma onset of ccw rotation of Rhodos constrains the onset of the formation of the south Aegean strike-slip system between 5.3 and 3.8 Ma. The formation of this strike-slip system is probably related to the interplay of oblique collision between the southeastern Aegean region and the northward moving African plate, the westward motion of Anatolia, gravitational spreading of the overthickened Aegean lithosphere and the recently postulated southwestward retreat of the African subducted slab along a subduction-transform edge-propagator fault.
Changes in vegetation and marine environments in the eastern Mediterranean (Rhodes, Greece) during the Early and Middle Pleistocene
Authors: Joannin Sébastien , Cornée Jean-Jacques , Moissette Pierre , Suc Jean-Pierre , Koskeridou Efterpi , Lécuyer Christophe , Buisine Cédric , Kouli Katarina , Ferry Serge
Published: October 2007

Pollen records, marine faunal associations and stable isotope compositions of sediments from Rhodes, Greece, have been determined to track environmental changes in the eastern Mediterranean during the Early and Middle Pleistocene. A detailed chronostratigraphic curve, based on magnetostratigraphic data, was obtained by correlating pollen spectra with the Mediterranean oxygen isotopic curve of Ocean Drilling Program Site 975. Five sedimentary sequences that correspond to marine oxygen isotope stage (MIS) 31–27 and to MIS 20–17 have been investigated in the confined Tsampika microbasin. High-amplitude
Pinus
variations confirm glacio-eustatic changes deduced from changes in marine faunal associations and sedimentary depositional environments. Reflecting climatic cycles identified in the marine carbonate oxygen isotope record, eight vegetation successions (characterized by the dominance first of mesothermic elements, then of mid- and high-altitude elements with
Pinus
, and ending with maxima in herb and steppe elements) have been documented. Most of them were probably driven by changes in insolation occurring in high northern latitudes (obliquity impact) during the late Early Pleistocene and early Middle Pleistocene.
Quaternary science 2007: a 50-year retrospective
Authors: Walker Mike , Lowe John
Published: October 2007

This paper reviews 50 years of progress in understanding the recent history of the Earth as contained within the stratigraphical record of the Quaternary. It describes some of the major technological and methodological advances that have occurred in Quaternary geochronology; examines the impressive range of palaeoenvironmental evidence that has been assembled from terrestrial, marine and cryospheric archives; assesses the progress that has been made towards an understanding of Quaternary climatic variability; discusses the development of numerical modelling as a basis for explaining and predicting climatic and environmental change; and outlines the present status of the Quaternary in relation to the geological time scale. The review concludes with a consideration of the global Quaternary community and the challenge for the future.