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Kinds of Contribution Terms modified by Contribution Selected AbstractsRELATIVE CONTRIBUTION OF ADDITIVE, DOMINANCE, AND IMPRINTING EFFECTS TO PHENOTYPIC VARIATION IN BODY SIZE AND GROWTH BETWEEN DIVERGENT SELECTION LINES OF MICEEVOLUTION, Issue 5 2009Reinmar Hager Epigenetic effects attributed to genomic imprinting are increasingly recognized as an important source of variation in quantitative traits. However, little is known about their relative contribution to phenotypic variation compared to those of additive and dominance effects, and almost nothing about their role in phenotypic evolution. Here we address these questions by investigating the relative contribution of additive, dominance, and imprinting effects of quantitative trait loci (QTL) to variation in "early" and "late" body weight in an intercross of mice selected for divergent adult body weight. We identified 18 loci on 13 chromosomes; additive effects accounted for most of the phenotypic variation throughout development, and imprinting effects were always small. Genetic effects on early weight showed more dominance, less additive, and, surprisingly, less imprinting variation than that of late weight. The predominance of additivity of QTL effects on body weight follows the expectation that additive effects account for the evolutionary divergence between selection lines. We hypothesize that the appearance of more imprinting effects on late body weight may be a consequence of divergent selection on adult body weight, which may have indirectly selected for alleles showing partial imprinting effects due to their associated additive effects, highlighting a potential role of genomic imprinting in the response to selection. [source] THE CONTRIBUTION OF SPONTANEOUS MUTATION TO VARIATION IN ENVIRONMENTAL RESPONSES OF ARABIDOPSIS THALIANA: RESPONSES TO LIGHTEVOLUTION, Issue 2 2005Christina M. Kavanaugh Abstract It has been hypothesized that new, spontaneous mutations tend to reduce fitness more severely in more stressful environments. To address this hypothesis, we grew plants representing 20 Arabidopsis thaliana mutationaccumulation (M-A) lines, advanced to generation 17, and their progenitor, in differing light conditions. The experiment was conducted in a greenhouse, and two treatments were used: full sun and shade, in which influx of red light was reduced relative to far-red. The shade treatment was considered the more stressful because mean absolute fitness was lower in that treatment, though not significantly so. Plants from generation 17 of M-A developed significantly faster than those from generation 0 in both treatments. A significant interaction between generation and treatment revealed that, counter to the hypothesis, M-A lines tended to have higher fitness on average relative to the progenitor in the shaded conditions, whereas, in full sun, the two generations were similar in fitness. A secondary objective of this experiment was to characterize the contribution of new mutations to genotype x environment interaction. We did not, however, detect a significant interaction between M-A line and treatment. Plots of the line-specific enviromental responses indicate no tendency of new mutations to contribute to fitness trade-offs between environments. They also do not support a model of conditionally deleterious mutation, in which a mutatn reduces fitness only in a particular environment. These results suggest that interactions between genotype and light environment previously documented for A. thaliana are not explicable primarily as a consequence of steady input of spontaneous mutations having environment-specific effects. [source] THE CONTRIBUTION OF AN HOURGLASS TIMER TO THE EVOLUTION OF PHOTOPERIODIC RESPONSE IN THE PITCHER-PLANT MOSQUITO, WYEOMYIA SMITHIIEVOLUTION, Issue 10 2003W. E. Bradshaw Abstract Photoperiodism, the ability to assess the length of day or night, enables a diverse array of plants, birds, mammals, and arthropods to organize their development and reproduction in concert with the changing seasons in temperate climatic zones. For more than 60 years, the mechanism controlling photoperiodic response has been debated. Photoperiodism may be a simple interval timer, that is, an hourglasslike mechanism that literally measures the length of day or night or, alternatively, may be an overt expression of an underlying circadian oscillator. Herein, we test experimentally whether the rhythmic response in Wyeomyia smithii indicates a causal, necessary relationship between circadian rhythmicity and the evolutionary modification of photoperiodic response over the climatic gradient of North America, or may be explained by a simple interval timer. We show that a day-interval timer is sufficient to predict the photoperiodic response of W. smithii over this broad geographic range and conclude that rhythmic responses observed in classical circadian-based experiments alone cannot be used to infer a causal role for circadian rhythmicity in the evolution of photoperiodic time measurement. More importantly, we argue that the pursuit of circadian rhyth-micity as the central mechanism that measures the duration of night or day has distracted researchers from consideration of the interval-timing processes that may actually be the target of natural selection linking internal photoperiodic time measurement to the external seasonal environment. [source] DIFFERENT CELL SIZE AND CELL NUMBER CONTRIBUTION IN TWO NEWLY ESTABLISHED AND ONE ANCIENT BODY SIZE CLINE OF DROSOPHILA SUBOBSCURAEVOLUTION, Issue 3 2003Federico C. F. Calboli Abstract Latitudinal genetic clines in body size occur in many ectotherms including Drosophila species. In the wing of D. melanogaster, these clines are generally based on latitudinal variation in cell number. In contrast, differences in wing area that evolve by thermal selection in the laboratory are in general based on cell size. To investigate possible reasons for the different cellular bases of these two types of evolutionary response, we compared the newly established North and South American wing size clines of Drosophila subobscura. The new clines are based on latitudinal variation in cell area in North America and cell number in South America. The ancestral European cline is also based on latitudinal variation in cell number. The difference in the cellular basis of wing size variation in the American clines, which are roughly the same age, together with the similar cellular basis of the new South American cline and the ancient European one, suggest that the antiquity of a cline does not explain its cellular basis. Furthermore, the results indicate that wing size as a whole, rather than its cellular basis, is under selection. The different cellular bases of different size clines are most likely explained either entirely by chance or by different patterns of genetic variance,or its expression,in founding populations. [source] SVEN LINDQVIST AND HIS SCIENTIFIC CONTRIBUTIONGEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 4 2007JAN O. MATTSSON First page of article [source] THE FLUCTUATIONS OF ITALIAN GLACIERS DURING THE LAST CENTURY: A CONTRIBUTION TO KNOWLEDGE ABOUT ALPINE GLACIER CHANGESGEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 3 2007MICHELE CITTERIO ABSTRACT. This paper describes the recent evolution of Italian glaciers through an analysis of all available terminus fluctuation data that the authors have entered in a glaciers database (named GLAD) containing 883 records collected on glaciers from 1908 to 2002. Furthermore, a representative subset of data (249 glaciers located in Lombardy) was analysed regarding surface area changes. For the analysis of terminus fluctuations, the glaciers were sorted by size classes according to length. The data showed that during the 20th century Italian Alpine glaciers underwent a generalized retreat, with one distinct and well documented readvance episode that occurred between the 1970s and mid-1980s, and a poorly documented one around the early 1920s. The rates of terminus advance and retreat have changed without significant delays for the larger glaciers with respect to the smaller ones. However, the smaller the glacier, the more limited the advance (if any) during the 1970s and early 1980s. The behaviour of glaciers shorter than 1 km appears to have changed in the last decade, and between 1993 and 2002 they retreated at a very high rate. The analysis of the subset of data led to a quanti-fication of surface reduction of c. 10% from 1992 to 1999 for glaciers in Lombardy. Small glaciers proved to contribute strongly to total area loss: in 1999, 232 glaciers (c. 90% of the total) were smaller than 1 km2, covering 27.2 km2 (less than 30% of the total area), but accounted for 58% of the total loss in area (they had lost 7.4 km2). [source] THE POSITIVE FINANCIAL CONTRIBUTION OF HOME-BASED PRIMARY CARE PROGRAMS: GENERATING REVENUE OR REDUCING HEALTH EXPENDITURE?JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 12 2008Jeremy M. Jacobs MBBS No abstract is available for this article. [source] LETHALITY CONTRIBUTION FROM THE TUBULAR HEAT EXCHANGER DURING HIGH-TEMPERATURE SHORT-TIME PROCESSING OF A MODEL LIQUID FOODJOURNAL OF FOOD PROCESS ENGINEERING, Issue 4 2004G.B. AWUAH ABSTRACT Experiments were conducted using Bacillus stearothermophilus spores in 0.5% w/w carboxymethylcellulose suspension to evaluate come-up contributions from the tubular heat exchanger. A lab-scale UHT/HTST simulator that allowed samples to be collected at the exit of the heat exchanger and holding tube was used with operating temperatures up to 270F. The bulk mean residence time in the heat exchanger ranged from 30 to 89 sec, while that in the holding tube ranged from 4 to 14 sec. It was observed that between 40% and 51% of the cumulative lethality () at the exit of the holding tube, was contributed by come-up in the tubular heat exchanger. This come-up contribution was determined on the basis of having anof 8.5 min in the holding tube alone. It was evident that come-up lethality will depend on product initial temperature, residence time and temperature history in the heat exchanger, with higher temperatures obviously contributing more lethality. Therefore, the entire aseptic system becomes even more complex since several critical parameters need to be monitored, controlled and documented. Experimental data compared favorably with computer-simulated data using the AseptiCALÔ software, with the software package giving more conservative results. Ultimately, come-up credit (CUC) should be tested on a pilot scale or industrial setup by way of reduced residence time (i.e. increased fluid flow rate), reduced holding tube length or temperature in order to determine if CUC can be applied towards the lethality required for the product. Monitoring and control devices become critical to ensure consistency and reproducibility in product residence time and time,temperature history, in the tubular heat exchanger. [source] THE CONTRIBUTION OF THIRD-PARTY INDICES IN ASSESSING GLOBAL OPERATIONAL RISKS;,JOURNAL OF SUPPLY CHAIN MANAGEMENT, Issue 4 2010KUNTAL BHATTACHARYYA In the face of global uncertainties and a growing reliance on third-party indices to obtain a snapshot of a country's operational risks, we explore the related questions: How accurately do third-party indices capture a country's operational risk, and how does the operational risk of the country, in turn, affect the volume of its import and export supply chains? We examine these questions by empirically investigating 81 member countries of the World Trade Organization (WTO) using archival data collected from UN agencies, independent think tanks, the WTO, and the Economist Intelligence Unit. We use seven third-party indices to gauge a country's internal environment and map those indices to corresponding country-specific operational risks to further understand the consequent effects of those operational risks on trading volume. Results provide strong evidence for the use of certain third-party indices in assessing operational risk. In addition, operational risks are found to negatively affect the volume of import and export supply chains, albeit in varying degrees. [source] CAPITAL ALLOCATION AND RISK CONTRIBUTION WITH DISCRETE-TIME COHERENT RISKMATHEMATICAL FINANCE, Issue 1 2009Alexander S. Cherny We define the capital allocation and the risk contribution for discrete-time coherent risk measures and provide several equivalent representations of these objects. The formulations and the proofs are based on two instruments introduced in the paper: a probabilistic notion of the extreme system and a geometric notion of the generator. These notions are also of interest on their own and are important for other applications of coherent risk measures. All the concepts and results are illustrated by JP Morgan's Risk Metrics model. [source] BIOEROSIVE STRUCTURES OF SCLEROZOAN FORAMINIFERA FROM THE LOWER PLIOCENE OF SOUTHERN SPAIN: A CONTRIBUTION TO THE PALAEOECOLOGY OF MARINE HARD SUBSTRATE COMMUNITIESPALAEONTOLOGY, Issue 4 2006A. SANTOS Abstract:, A palaeoecological study of sclerozoan foraminifera of the families Saccamminidae (aff. Sagenina), Lituolidae (Placopsilina), Cibicididae (Cibicides, Dyocibicides, Cibicidella) and Planorbulinidae (Planorbulina and Planorbulinella) that colonized epifaunal bivalves (ostreids and pectinids) during the early Pliocene in southern Spain has led to the recognition of two new boring ichnogenera: Camarichnus ichnogen. nov., with two ichnospecies, C. subrectangularis ichnosp. nov. and C. arcuatus ichnosp. nov., and Canalichnus ichnogen. nov., with one ichnospecies, C. tenuis ichnosp. nov. The first two ichnospecies were produced by adnate lituolids and cibicidids, the last by saccamminids. Their recognition is very important when quantifying populations of these organisms. Colonisation took place after death of the host bivalves, when they acted as very stable substrates whose topography probably controlled the initial settlement pattern of the foraminifera. The colonisation sequence started with the foraminifera (lituolids-saccamminids-cibicidids-planorbulinids) and was followed by vermetid gastropods, serpulids, spirorbids, cheilostome bryozoans and/or ostreids. Preferred orientations and overgrowth relationships between cheilostome bryozoans and serpulids have been detected in this material. [source] CHAOS THEORYAS A NEW PARADIGM IN PSYCHOANALYSIS: A CONTRIBUTION TO THE DISCUSSION OF MODELSTHE INTERNATIONAL JOURNAL OF PSYCHOANALYSIS, Issue 2 2002Warren R. Procci First page of article [source] ANAESTHESIA AND ANALGESIA: CONTRIBUTION TO SURGERY, PRESENT AND FUTUREANZ JOURNAL OF SURGERY, Issue 7 2008Edward Shipton Anaesthetists provide comprehensive perioperative medical care to patients undergoing surgical and diagnostic procedures, including postoperative intensive care when needed. They are involved in the management of perioperative acute pain as well as chronic pain. This manuscript considers some of the recent advances in modern anaesthesia and their contribution to surgery, from the basic mechanisms of action, to the delivery systems for general and regional anaesthesia, to the use of new drugs and new methods of monitoring. It assesses the resulting progress in acute and chronic pain services and looks at patient safety and risk management. It speculates on directions that may shape its future contributions to the management of the patient undergoing surgery. [source] SHORT CONTRIBUTION: The latest endangered species in Australia: A tobacco-smoking veterinarianAUSTRALIAN VETERINARY JOURNAL, Issue 9 2010DR Smith The results of a tobacco smoking survey conducted among veterinarians in Queensland, Australia, during 2007 are presented. Of the 567 participants only 3% reported being current smokers, 24% were ex-smokers and 73% had never smoked. The prevalence of smoking was similar among males and females, and the highest smoking rate was reported among veterinarians aged 31,40 years. However, the rate of never-smokers was strongly and negatively correlated with age, and the proportion of ex-smokers increased with age. Encouragingly, the results from this study suggest that tobacco use has all but disappeared from the Australian veterinary profession in recent years. [source] ENACTMENT: SOME THOUGHTS ABOUT THE THERAPIST'S CONTRIBUTIONBRITISH JOURNAL OF PSYCHOTHERAPY, Issue 4 2006Dawn Devereux ABSTRACT This paper examines three instances of enactment, which occurred in the early stages of a thrice-weekly therapy. The emphasis is on both the origins and consequences of the therapist's contribution. Particular attention is paid to the unconscious nature of enactment, as a phenomenon that can precipitate both a refusal and an actualization of the patient's transference; the former, in this case, leading to further acting out and the latter to malignant regression. [source] PRE-ECLAMPSIA: CONTRIBUTION OF MATERNAL CONSTITUTIONAL FACTORS AND THE CONSEQUENCES FOR CARDIOVASCULAR HEALTHCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 9 2006Anne Barden SUMMARY 1Pre-eclampsia is a serious complication of pregnancy that is potentially life threatening for both the mother and baby. It encompasses a number of abnormalities that may be present in other clinical conditions. 2A placenta is essential for the development of pre-eclampsia and can be important in the pathogenesis of pre-eclampsia. Normal pregnancy is associated with remodelling of the maternal spiral arteries, which deliver blood to the placental villous space. Remodelling involves invasion by placental cytotrophoblasts that cause the maternal spiral arteries to lose their smooth muscle and become capacitance vessels; this process, known as placentation, is complete by 20 weeks of pregnancy. Poor placentation is associated with small-for-gestational-age fetuses and some cases of pre-eclampsia. It is thought that poor placentation can result in a hypoxic placenta that releases ,toxic substances' into the maternal circulation, contributing to the maternal syndrome. A number of candidate ,toxic substances' have been proposed, but none is universally raised in pre-eclampsia. 3Although the placenta is necessary for the development of pre-eclampsia, the extent to which placental abnormalities contribute to the condition varies. It is becoming apparent that maternal constitutional factors may also be important in this syndrome. Underlying hypertension, diabetes and obesity strongly predispose to pre-eclampsia. However, a continuum of risk may exist for blood pressure, bodyweight, glucose and lipids, which, in combination with each other and some degree of placental abnormalities, may lead to the development of pre-eclampsia. 4The present review will focus on the maternal constitutional factors that define the metabolic syndrome and examine their contribution to pre-eclampsia and the long-term consequences for cardiovascular health. [source] CONTRIBUTION OF PROSTANOID TP RECEPTORS TO THE PRESSOR AND INTRARENAL HAEMODYNAMIC RESPONSE TO ENDOTHELINCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 3 2006Jan Michael Williams SUMMARY 1Previous studies have shown that endothelin (ET)-1 stimulates thromboxane (Tx)A2 production and so we hypothesized that inhibiting prostanoid TP receptors would prevent the pressor and intrarenal haemodynamic response to an acute infusion of ET-1. 2Male Sprague-Dawley rats were anaesthetized with Inactin (Sigma Chemical, St Louis, MO, USA; 50 mg/kg) and catheters were inserted into the femoral artery and vein for recording mean arterial pressure (MAP) and infusion of ET-1 and receptor antagonists, respectively. A jugular vein catheter was used for the infusion of bovine serum albumin (6.2% in saline) during surgery (1.25% bodyweight). The pressor response to a 1 h infusion of ET-1 (6 pmol/kg per min) was determined in rats that had been pretreated with vehicle (0.9% NaCl) or the TP receptor antagonist SQ29548 (2 mg/kg per h). Laser Doppler single-optic fibres were implanted in the left kidney for the measurement of medullary blood flow (MBF) and cortical blood flow (CBF). 3Prostanoid TP receptor blockade completely inhibited the acute pressor response to ET-1; the change in MAP was 14 2% versus -3 4% in vehicle and SQ29548 groups, respectively (P < 0.05). Endothelin-1 reduced CBF (-15.2 3.3%), a response that was not significantly changed by SQ29548 (-6.2 7.6%). Similarly, the ET-1-mediated response in MBF was not altered by the TP receptor antagonist (7.7 4.9 vs 6.5 5.2%). 4To determine the influence of the ETB receptor in modulating the response to ET-1 during TP receptor blockade, additional groups were pretreated with A-192621, an ETB receptor-selective antagonist (10 mg/kg, i.v.). A-192621 potentiated the increase in MAP produced by ET-1 (32 5%; P < 0.05 vs ET-1 alone). SQ29548 significantly inhibited, but did not completely block, the increase in MAP produced by ET-1 during ETB antagonist treatment (18 4%; P < 0.05). Endothelin-1-induced decreases in CBF were significantly enhanced in rats that were pretreated with A-192621, whereas ET-1 also significantly decreased MBF following A-192621 treatment. During ETB receptor blockade, TP receptor inhibition had no effect on the ET-1-mediated response of CBF and MBF. 5These results suggest that TP receptor activation is not involved in the renal haemodynamic responses to ET-1. However, TP receptor activation contributes to the acute pressor response to ET-1, but does not account for the potentiated increase in MAP during ETB receptor blockade. [source] RELATIVE CONTRIBUTION OF THE PRENATAL VERSUS POSTNATAL PERIOD ON DEVELOPMENT OF HYPERTENSION AND GROWTH RATE OF THE SPONTANEOUSLY HYPERTENSIVE RATCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 1-2 2006Robert Di Nicolantonio SUMMARY 1To determine the relative roles of the prenatal and postnatal (preweaning) environment on the development of blood pressure and growth rate in the spontaneously hypertensive rat (SHR) of the Okamoto strain, we used combined embryo transfer and cross-fostering techniques between SHR and normotensive Wistar-Kyoto (WKY) rats to produce offspring whose development was examined during the first 20 weeks of life. 2We measured litter sizes, bodyweights and tail-cuff blood pressures in offspring at 4, 8, 12 and 20 weeks of age. We also recorded heart, kidney and adrenal weights at 20 weeks of age, when the study concluded. 3We found that both the in utero and postnatal environments provided by the SHR mother could significantly affect WKY rat offspring growth rates, but blood pressure was unaffected in this strain. In SHR offspring, the SHR maternal in utero and suckling period both contributed to the rate of blood pressure development in the SHR, but not the final blood pressure of offspring at 20 weeks of age. This effect was greater for male than female offspring. Organ weights were largely unaffected by the perinatal environment in either strain. 4We conclude that although the SHR maternal in utero and immediate postnatal environment both contribute to the rate of blood pressure development in the SHR, they do not appear to contribute to the final blood pressure of offspring at maturity. The SHR maternal environment also alters growth rate that may, in turn, underlie these effects on SHR blood pressure development, particularly in males. [source] DO STOCK RETURNS VARY WITH CAMPAIGN CONTRIBUTIONS?ECONOMICS & POLITICS, Issue 3 2010BUSH VS. I examine the relation between campaign contributions and stock returns during the Florida recount period of the 2000 presidential elections. Using the full population of publicly traded firms, I find an economically significant positive (negative) relation between pre-election campaign contributions to Bush (Gore) and stock returns during the 37-day election recount period. This relation exists for both the level and partisanship of contributions, and exists incrementally at both the firm and industry levels. These relations are robust to several different specifications, including alternative event windows that exclude the potentially confounding House/Senate races. The firm-level analysis is consistent with contributions being influence-motivated. [source] CAFTA, CAMPAIGN CONTRIBUTIONS, AND THE ROLE OF SPECIAL INTERESTSECONOMICS & POLITICS, Issue 3 2010JAMES M. DEVAULT This paper analyzes the passage of the Central American Free Trade Agreement (CAFTA) in 2005, paying particular attention to the role of campaign contributions. The CAFTA vote is significant in that the context in which it occurred was one in which campaign contributions were more likely to influence votes. By more carefully identifying the special interest groups actively involved in the CAFTA debate, I provide a more accurate assessment of the impact of the contributions made by these groups. I use instrumental variables to control for the potential endogeneity of campaign contributions and find that these contributions played at best a secondary role in determining the outcome of the CAFTA vote in the U.S. House of Representatives. [source] CONTRIBUTIONS AND ELECTIONS WITH NETWORK EXTERNALITIESECONOMICS & POLITICS, Issue 1 2005Adam Meirowitz This paper develops a model of campaign contributions and electoral competition. Contributors have separable preferences over policy and the electoral success of the candidate they support, as in influence buying. Policy preferences are single peaked over a single policy dimension. A candidate's chances of victory are increasing in the relative size of her war chest. In equilibrium, potential contributors balance incentives to donate to a candidate that is desirable on policy grounds and ensuring that they back the likely winner. With exogenous candidate positions, we find conditions under which, in equilibrium, contributors donate to the candidate that is less desirable on policy grounds solely because they consider the candidate viable. We also find that there is a degree of indeterminacy, wherein multiple equilibria inducing different lotteries over the final policy often exist. With endogenous candidate locations, we find that while median policies are always supportable as equilibrium, it is often the case that any pair of candidate locations is supportable in equilibrium. These results suggest that in settings with substantial influence buying, median policy interests may not be represented. [source] JOHN DEWEY'S CONTRIBUTIONS TO AN EDUCATIONAL PHILOSOPHY OF INTELLECTUAL DISABILITYEDUCATIONAL THEORY, Issue 1 2008Scot Danforth In this article Scot Danforth takes as his project addressing that division from the perspective of a Deweyan philosophy of the education of students with intellectual disabilities. In 1922, John Dewey authored two articles in New Republic that criticized the use of intelligence tests as both undemocratic and impractical in meeting the needs of teachers. Drawing from these two articles and a variety of Dewey's other works, Danforth puts forward a Deweyan educational theory of intellectual disability. This theory is perhaps encapsulated in Dewey's observation that "The democratic faith in human equality is belief that every human being, independent of the quantity or range of his personal endowment, has the right to equal opportunity with every other person for development of whatever gifts he has."1 [source] SNOWSHED CONTRIBUTIONS TO THE NOOKSACK RIVER WATERSHED, NORTH CASCADES RANGE, WASHINGTON,GEOGRAPHICAL REVIEW, Issue 2 2002ANDREW BACH ABSTRACT. Meltwater contributes to watershed hydrology by increasing summer discharge, delaying the peak spring runoff, and decreasing variability in runoff. High-elevation snowshed meltwater, including glacier-derived input, provides an estimated 26.9 percent of summer streamflow (ranging annually from 16 to 40 percent) in the Nooksack River Basin above the town of Deming, Washington, in the North Cascades Range. The Nooksack is a major spawning river for salmon and once was important for commercial, recreational, and tribal fishing, and in the past its flow met the demands of both human and aquatic ecosystems. But the river is already legally overallocated, and demand is rising in response to the rapidly growing human population. Variability in snowshed contributions to the watershed is considerable but has increased from an average of 25.2 percent in the 1940s to an average of 30.8 percent in the 1990s. Overall stream discharge shows no significant increase, suggesting that the glaciers are melting, and/or precipitation levels (or other hydrologic factors) are decreasing at about the same rate. If glaciers continue to recede, they may disappear permanently from the Cascades. If that occurs, their summer contribution to surface-water supplies will cease, and water-management policies will need drastic revision. [source] CONTRIBUTIONS TO UNDERSTANDING SEAWEEDS IN COASTAL COMMUNITIESJOURNAL OF PHYCOLOGY, Issue 2001Article first published online: 24 SEP 200 Dawes, C. J. Department of Biology, University of South Florida, Tampa, Florida 33620 The goal of my presentation is to review several studies that have enhanced our understanding of the effects of abiotic factors on coastal and estuarine seaweed populations. Accordingly, I will introduce a few key papers dealing with five major abiotic factors-i.e. salinity, temperature, desiccation, water motion, and illumination. Foremost, the salinity tolerance studies of Russell and Bolton (1975) have broad applicability to estuarine seaweeds, while the osmoregulatory studies of Bisson and Kirst (1979) are also significant. Biebl's (1972) review of his earlier studies on temperature tolerances in diverse seaweeds were pivotal. Johnston and Raven's (1986) studied the effects of desiccation on the fucoid brown alga Ascophyllum nodosum, while similar studies on the saccate brown seaweed Colpomenia peregrina were conducted by Oates (1985). Lewis (1968) conducted early synoptic evaluations of the effects of water movement on rocky shore communities, while Kitching and Ebling (1967) gave detailed assessments of seaweed populations within estuarine tidal rapids in Ireland. Basically estuarine tidal rapids represent areas of enhanced nutrients, oxygen and light availability, plus reduced sedimentation (Mathieson et al. (1983). The physiological effects of light have probably been evaluated more than any single abiotic factor and two areas of importance are cited here. The critical papers by Levring (1947) on submarine illumination and those of Ramus (1978) and Littler and Littler (1980) on algal form and light response. Several areas of future studies are also suggested, which may further enhance our understanding of seaweed adaptations. In summary, five major abiotic factors affecting coastal and estuarine seaweed populations will be discussed, their importance to seaweeds noted, and "key" findings for several significant papers summarized. [source] THE ECONOMIC VALUE OF ENVIRONMENTAL RESEARCH IN UNDERSTANDING THE RELATIVE CONTRIBUTIONS OF SOURCES OF NUTRIENTS TO COASTAL WATERSNATURAL RESOURCE MODELING, Issue 2 2006DI JIN ABSTRACT. We model the value of environmental research in the presence of uncertainty about thesources of environmental pollutants and natural processes affecting the level of pollution. The model may be used to estimate the value of environmental research directed at resolving the uncertainty. We illustrate the model using a numerical simulation of a hypothetical case involving nutrient pollution of coastal waters. We show that the ex ante value of research is positively related to the level of uncertainty. There is a diminishing return with respect to the level of research investment. We find that research is more valuable ex post if it leads to unexpected findings. [source] IMAGING GENETICS: CONTRIBUTIONS FROM TWIN STUDIESPSYCHOPHYSIOLOGY, Issue 2008Article first published online: 12 AUG 200 No abstract is available for this article. [source] PESSIMISM OR OPTIMISM: A JUSTIFICATION TO VOLUNTARY CONTRIBUTIONS TOWARD ENVIRONMENTAL QUALITY,AUSTRALIAN ECONOMIC PAPERS, Issue 4 2009JOHANNA ETNER This article analyses the determinants of voluntary contribution to environmental quality by introducing the perception of environmental risk. We consider individuals who are aware both of the impact of their voluntary contributions and of the quality of the current environment on the future quality of environment. Their preferences are represented by the RDU model. We distinguish three kinds of effect: environmental quality, wealth and risk perception. The first effects are not always sufficient to explain agents' implication in the improvement of environmental quality. [source] Roughness Characterization through 3D Textured Image Analysis: Contribution to the Study of Road Wear LevelCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 2 2004M. Khoudeir The microtexture is defined as surface irregularities whose height ranges from 0.001 mm to 0.5 mm and whose width is less than 0.5 mm (Alvarez and Mprel, 1994). The deterioration due to the road traffic, especially polishing effect, involves a change in the microtexture. So, we suggest a method to characterize, through image analysis, wear level or microroughness of road surfaces. We propose then, on one hand a photometric model for road surface, and, on the other hand, a geometrical model for road surface profile. These two models allow us to develop roughness criteria based on the study of the statistical properties of: the distribution of the gray levels in the image, the distribution of the absolute value of its gradient, the form of its autocorrelation function, and the distribution of its curvature map. Experiments have been done with images of laboratory-made road specimens at different wear levels. The obtained results are similar to those obtained by a direct method using road profiles. [source] Contribution to the study of elastic properties of KGd(WO4)2:Er3+ single crystals by Brillouin spectroscopyCRYSTAL RESEARCH AND TECHNOLOGY, Issue 12 2009D. Kasprowicz Abstract In this paper we present the study of the acoustic phonons propagating in Er3+ -doped KGd(WO4)2 single crystals by Brillouin spectroscopy. For the investigated crystals the velocities of the longitudinal and transverse acoustic phonons [100], [010], [001], [101] and [110] have been determined. Moreover, the values of the elastic constants: C22, C44 and C66 of Er3+ -doped KGd(WO4)2 single crystals have been estimated. It was revealed that the presence of the Er3+ -ions in KGd(WO4)2 crystals, for the used doping concentration 1 at% does not influence their elastic properties. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Contribution to the stability analysis of the dewetted Bridgman growth under microgravity conditionsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 6 2004L. Bizet Abstract Experimental observations show that the gap between the sample and the crucible, commonly obtained after solidification in microgravity, is remarkably stable. With the aim to understand the reason of this stability, the dewetting phenomenon is studied by Lyapunov's method. After a short review of the existing mechanisms leading to dewetting, the open smooth crucible configuration is chosen as the most representative. The analytical stability analysis, taking into account geometrical and thermal effects, performed under some boundary heat transfer approximations, shows that, in most cases, the dewetting process is intrinsically stable. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | ||||||||||||||||||||||||||||||||||||||||