bluuebunny/crossref_metadata_2025_split huggingface dataset:
Magnetic Resonance Imaging of the Hypothalamic‐Neurohypophyseal System
Authors: Fujisawa I. 
Published: April 2004

AbstractMagnetic resonance imaging (MRI) is a revolutionary advance in diagnostic imaging of the hypothalamic‐neurohypophyseal system (HNS). The detailed anatomy of the sellar and parasellar region is clearly visible using MRI, because it has no bony artifacts and multidirectional capability. The posterior lobe of the pituitary gland displays a characteristic bright signal on the MR T1‐weighted image (T1WI), and is distinctly separated from the anterior lobe. The bright signal is absent in patients with central diabetes insipidus, and is thought to reflect normal vasopressin storage in the posterior lobe. The signal intensity ratio of the posterior lobe to the pons on T1WI is strongly correlated with vasopressin content in the posterior lobe. In addition to the morphological evaluation, MRI provides unique information concerning the function of the HNS. The MRI findings of the HNS (normal condition, central diabetes insipidus, a depleted posterior lobe, an ectopic posterior lobe, and a damming‐up phenomenon of the neurosecretory vesicles in the pituitary stalk) are demonstrated in this article.
Neural Pathways Controlling Central and Peripheral Oxytocin Release During Stress
Authors: Onaka T. 
Published: April 2004

AbstractOxytocin is released from the pituitary gland in response to a variety of stressful stimuli, including noxious stimuli, conditioned fear and exposure to novel environments. These responses are believed to be mediated, at least in part, by noradrenergic projections from the medulla oblongata, and some of these noradrenergic neurones also contain prolactin‐releasing peptide (PrRP). Central administration of either PrRP or noradrenaline stimulates oxytocin secretion into the circulation. Stressful stimuli activate PrRP‐containing noradrenergic neurones in the medulla oblongata, and it is thus possible that PrRP/noradrenergic projections to the hypothalamus mediate oxytocin responses to stressful stimuli. Here, the roles of brainstem PrRP/noradrenergic projections to the hypothalamus in oxytocin responses to different kinds of stressful stimuli are reviewed, with a particular emphasis on conditioned fear. Roles of dendritic oxytocin release during stress and metabolic factors affecting stress pathways are also discussed.
Oestrogen Receptor β: Role in Neurohypophyseal Neurones
Authors: Sladek C. D. , Somponpun S. J. 
Published: April 2004

AbstractThe robust expression of oestrogen receptor β (ER‐β) in magnocellular vasopressin neurones has focused attention on the role of this receptor and the gonadal steroids in the regulation of vasopressin secretion. Although the effects of gonadal steroids on vasopressin secretion have been the subject of many studies, there is no consensus in the literature as to their role. Possible reasons for the diverse findings are discussed, including diversity in the types, site and level of expression of steroid receptors across species, gender and physiological conditions. The physiological regulation of expression is of particular interest because ER‐β mRNA expression in vasopressin neurones is inversely correlated to the osmotic state of the animal. Chronic hyperosmolality inhibits ER‐β mRNA expression in magnocellular vasopressin neurones, while chronic hypo‐osmolality enhances expression. This is consistent with an inhibitory role for ER‐β because hyperosmolality is a potent stimulus for vasopressin secretion, whereas vasopressin secretion is maximally inhibited by chronic hypo‐osmolality. An inhibitory role is also indicated by in vitro experiments demonstrating inhibition of osmotically stimulated vasopressin secretion by oestrogen and testosterone, and ER‐β mediated inhibition of NMDA‐stimulated vasopressin secretion. The challenge remains to elucidate the mechanism of this inhibition, and to understand its significance for maintenance of whole‐body fluid and electrolyte homeostasis.
Nationhood, Communism and State Legitimation
Authors: Schöpflin George 
Published: April 2004

Abstract. Four states have disappeared as a result of the collapse of communism and many others have come into being. I want to look at the reason why these states have disappeared, what this says about the nature of state‐sustaining ideologies and what the disappearance tells us about the relationship between statehood and nationhood. I will also look at the effectiveness of communism as a state‐sustaining ideology. The four are, obviously, the Soviet Union, Yugoslavia, Czechoslovakia and East Germany. In each case, the survival of the state was linked to communism and the end of communism brought their continued existence into jeopardy. I shall not be looking at the Soviet Union in detail.Broadly, the construction of political identities can come about in two ways – by ethnicity or by the state. Each gives rise to a different set of loyalties, creates its own panoply of rituals etc. When the two coincide, the mythical nation‐state can be said to be in being, but this hardly exists in reality (Iceland may be the sole exception in Europe).
Theorising Ethnicity and Ethnic Communalisations at the Margins: From Quebec to the World System
Authors: Juteau Danielle 
Published: April 2004

Abstract.This article explores the changing and competing relations between multiple forms of ethnic communalisations in Quebec, as the Quebecois nation is now confronted by pressures to redefine its boundaries in more inclusive terms. This specific case allows me to address two major theoretical questions. First, I re‐examine the usefulness of the dominant mode of classification of nations, the binary opposition between ethnic and territorial nations. I then develop a perspective which makes visible the construction of the external and internal dimensions of ethnic boundaries as well as their interrelations.Focusing on processes of ethnic communalisation allows me to transcend both the former static, primordialist, empiricist, essentialist, naturalist and absolutist conception of ethnicity and some of the more recent radical constructivist conceptions which envisage ethnicity as an infinite slide of the signifier, a fantasy, a game. Finally, I locate ethnic communalisationsandtheir theorisation within the framework of modernity and of the world system; by recognising the unequal relations which often underlie ethnic forms of communalisation, it becomes possible to decentre the conceptualisation and the theorisation of ethnicity, which are inseparable from ethnic relations themselves and from the position held by different countries within the world system.
A Theory of Ethnic Group Boundaries
Authors: Chai Sun‐Ki 
Published: April 2004

Abstract.Despite widespread agreement that ethnic boundaries are malleable rather than fixed, theories of ethnicity and collective action have been unable to adequately explain why individuals choose to mobilise collectively within particular boundaries rather than others. The boundaries of groups engaging in ethnic collective action are always taken for granted at some level rather than problematised. This leads to an undesirable reification of ethnic groups as actors.The theory presented in this article integrates a social psychological view of motivation with a rational choice view of action to provide a systematic way of predicting the boundary location of ethnic groups that begin to mobilise in societies undergoing modernising structural change. It first focuses on the link between cooperation and altruism in small communities. It then predicts how altruistic preferences, in conjunction with structural factors and rational behaviour, will generate boundaries for larger‐scale ethnic collective action that transcends yet incorporates such communities. The theory's predictions are then applied to explain the location of group boundaries in four very prominent cases of ethnicity ‘creation’ and collective action in this century.
Nationalism, Loss‐Gain Framing and the Confederate States of America
Authors: Taubman Geoffry L. 
Published: April 2004

Abstract.In recent years, numerous states have become racked with internal secessionist strife. Why have calls for independence by regional subgroupings been heeded even after long periods of inter‐ethnic peace or in regions without any previous history of secessionist activity? I contend that this question can be answered by examining the phenomenon ofloss‐gain framing, in which people are motivated to adopt risky stratagems, like secession, due to fears of unacceptable losses.This article examines the enigma of why most white American Southerners in 1861 willingly fought for the establishment of the Confederacy, a nation based upon slavery, despite the fact that most Southerners did not own slaves and had continuously rejected secessionist appeals for years. Confederate President Jefferson Davis overcame this reluctance by emphasising what all Southerners – slaveholder and non‐slaveholder alike – would lose by remaining in the United States rather than accentuating what would be gained by secession.
The Ethnic Dimension to Bureaucratic Encounters in Postcommunist Europe: Perceptions and Experience
Authors: Grødeland Åse B. , Miller William L. , Koshechkina Tatyana Y. 
Published: April 2004

Abstract. In a survey of public opinion about the behaviour of officials in four postcommunist countries ‐Ukraine, Bulgaria, Slovakia and the Czech Republic – we found pervasive suspicions of ethnic bias. Although ethnic minorities themselves were particularly suspicious of officials, there was a consensus across both ethnic majorities and minorities that officials favoured their own ethnic group and discriminated against others.Suspicion may distort reality, however. Citizens' own reports of dealing with officials generally revealed much less ethnic discrimination in their personal experience than in their suspicions, presumptions and perceptions. Either suspicion exaggerated reality or general perceptions of bias focused on the most badly treated, rather than the most numerous, minorities.Ethnic minorities themselves behaved in different ways towards officials. Amongst the ethnic minorities covered in this study, only Gypsies displayed the characteristics of hopelessness and ‘exclusion’. Some minorities behaved much like the titular nationality. But most compensated for their minority status by engaging more than the titular nationality in a wide range of strategies to influence officials ‐including the use of contacts, presents and bribes. Conversely, in areas where an ethnic minority was concentrated locally, members of the titular nationality displayed a measurably defensive reaction and a somewhat heightened degree of vigilance.The paper is based on a total of 6,050 interviews made in the winter of 1997–8, including representative country‐wide samples and special additional samples in areas where ethnic minorities were concentrated. It compares the four titular nationalities with eight ethnic minorities.This research was funded by the ODADFID (formerly Overseas Development Administration, now Department for International Development) under grant R6445 to Miller and Koshechkina, and by the ESRC (Economic and Social Research Council) under grant R222474 to Miller and Grødeland. Translation and fieldwork was carried out by OPW (Opinion Window) of Prague and MVK of Bratislava both under the direction of Ladislav Koppl, CSD (Centre for the Study of Democracy) of Sofia under the direction of Alexander Stoyanov, and GfK‐USM (Ukrainian Surveys and Market Research) of Kyiv under the direction of Tatyana Koshechkina.
Non‐invasive monitoring of haemoglobin concentration in paediatric surgical patients using near‐infrared spectroscopy*
Authors: Dullenkopf A. , Lohmeyer U. , Salgo B. , Gerber A. C. , Weiss M. 
Published: April 2004

SummaryWe evaluated the near‐infrared spectroscopy based tissue haemoglobin index for continuous non‐invasive monitoring of haemoglobin concentration during paediatric surgery. Blood samples from 40 children (from birth to 16 years old) were analysed oximetrically. From the first blood sample the tissue haemoglobin index/haemoglobin concentration coefficient was calculated for further tissue haemoglobin index‐derived haemoglobin concentrations in each patient. Comparison of corresponding values revealed a bias and precision of – 0.02 and 5.41 g.l−1, respectively. Sensitivity and specificity of tissue haemoglobin index were 73.1% and 70.0%, respectively, for predicting falling haemoglobin concentration values. Currently, the tissue haemoglobin index is not suitable for monitoring haemoglobin concentration in children undergoing surgery.
Evidence‐based strategies for preventing drug administration errors during anaesthesia
Authors: Jensen L. S. , Merry A. F. , Webster C. S. , Weller J. , Larsson L. 
Published: April 2004

SummaryWe developed evidence‐based recommendations for the minimisation of errors in intravenous drug administration in anaesthesia from a systematic review of the literature that identified 98 relevant references (14 with experimental designs or incident reports and 19 with reports of cases or case series). We validated the recommendations using reports of drug errors collected in a previous study. One general and five specific strong recommendations were generated: systematic countermeasures should be used to decrease the number of drug administration errors in anaesthesia; the label on any drug ampoule or syringe should be read carefully before a drug is drawn up or injected; the legibility and contents of labels on ampoules and syringes should be optimised according to agreed standards; syringes should (almost) always be labelled; formal organisation of drug drawers and workspaces should be used; labels should be checked with a second person or a device before a drug is drawn up or administered.
Mortality dynamics ofDaphniain contrasting habitats and their role in ecological divergence
Authors: Dudycha Jeffry L. 
Published: April 2004

Summary1. TheDaphnia pulex‐pulicariaspecies complex has been proposed as an example of rapid ecological speciation, associated with divergence along the gradient of waterbody size from temporary ponds to deep, stratified lakes. However, this divergence is incomplete, and thus represents an opportunity to study ecological divergence as it is occurring.2. Dynamics of twelve populations ofDaphniain thepulex‐pulicariaspecies complex were monitored over 1 year. Six temporary pond populations and six permanent lake populations were compared to evaluate demographic differences that may contribute to ecological divergence in this complex.3. Pond populations experienced greater changes in density, which were reflected in more extreme growth rates, higher birth rates and higher mortality rates than those of lake populations.4. Mitochondrial DNA was isolated from up to three clones from each population, the D‐loop of the control region was sequenced, and a phylogenetic tree was constructed. This tree revealed two strongly supported clades. The clades were not congruent with habitat type and nominal status, indicating that interhabitat gene flow occurs easily and that the nominal taxa are incompletely diverged.5. Published reports of genetic life history differences in theD. pulex‐pulicariacomplex are consistent with the demographic differences reported here. This suggests that ecological differences between the habitats are selectively maintaining trait differences despite the possibility for genetic exchange. Thus, these taxa may be at the inception of ecological speciation.
Invasive species profiling? Exploring the characteristics of non‐native fishes across invasion stages in California
Authors: Marchetti Michael P. , Moyle Peter B. , Levine Richard 
Published: April 2004

Summary1. The global spread of non‐native species is a major concern for ecologists, particularly in regards to aquatic systems. Predicting the characteristics of successful invaders has been a goal of invasion biology for decades. Quantitative analysis of species characteristics may allow invasive species profiling and assist the development of risk assessment strategies.2. In the current analysis we developed a data base on fish invasions in catchments throughout California that distinguishes among the establishment, spread and integration stages of the invasion process, and separates social and biological factors related to invasion success.3. Using Akaike's information criteria (AIC), logistic and multiple regression models, we show suites of biological variables, which are important in predicting establishment (parental care and physiological tolerance), spread (life span, distance from nearest native source and trophic status) and abundance (maximum size, physiological tolerance and distance from nearest native source). Two variables indicating human interest in a species (propagule pressure and prior invasion success) are predictors of successful establishment and prior invasion success is a predictor of spread and integration.4. Despite the idiosyncratic nature of the invasion process, our results suggest some assistance in the search for characteristics of fish species that successfully transition between invasion stages.
Decline in the quality of suspended fine particulate matter as a food resource for chironomids downstream of an urban area
Authors: Rosi‐Marshall Emma J. 
Published: April 2004

Summary1. Urbanization and its associated contamination could degrade the quality of suspended fine particulate organic matter (SFPM) (20 μm to 1 mm) as a food resource for aquatic insects. SFPM was collected at four sites along the main stem of the Chattahoochee River, which drains metropolitan Atlanta at base and high flow during four seasons.2. Composition of SFPM was estimated using measures conventionally associated with food quality: bacteria, N/C ratio, caloric content, % inorganic, and % lipids, and metal (Cd, Cu, Pb, and Zn) concentration. In SFPM collected during base flow, % inorganic matter, calories, Cu, Pb, and Zn concentrations increased with cumulative permitted wastewater treatment discharge (an indicator of extent of urbanization upstream). In SFPM samples collected during high flow, % diatoms, Cu, Pb and Zn concentrations increased with urbanization.3. A growth assay was used as an integrated and direct measure of SFPM quality as a food resource. The instantaneous growth rate (IGR) of chironomids fed SFPM collected during base flow declined downstream of the city. IGRs of chironomids fed SFPM collected at all sites during high flow were as low as the lowest IGR measured during base flow.4. Insects fed SFPM collected from the Chattahoochee River had IGRs only 20% of those of chironomids fed SFPM collected from the Little Tennessee River, a relatively undisturbed river in North Carolina. The mortality rate of chironomids fed SFPM was not different among sites or rivers. While the decline in SFPM quality in the Chattahoochee River is probably attributable to some aspect of urbanization, the decline was not related to conventional measures of food quality or metal contamination.
Zebra mussel colonisation of soft sediments facilitates invertebrate communities
Authors: Beekey M. A. , McCabe D. J. , Marsden J. E. 
Published: April 2004

Summary1. We examined the effect of zebra mussel colonisation on invertebrate communities inhabiting soft sediments in two bays along the Vermont shoreline of Lake Champlain, U.S.A.2. In summer 2001, we conducted manipulative experiments (addition and removal of zebra mussel colonies) with respective controls to assess the effect of colonies on invertebrate abundance, richness, and position within sediments (within colony versus underlying colony) and compared these data to comparative studies of natural communities in summer 2002.3. Split core samples were taken two months after the manipulation and the following year so that we could quantify individuals and species inhabiting zebra mussel colonies separately from those in sediments underlying zebra mussel colonies and adjacent sediments lacking zebra mussels.4. Zebra mussel‐covered sediments supported more abundant and richer invertebrate communities than adjacent sediments lacking zebra mussels.5. Abundance and richness patterns in zebra mussel‐addition and removal treatments closely paralleled those in natural communities.6. Despite severe oxygen depletion at the interface of underlying sediments and overlying zebra mussel colonies, most infaunal invertebrates responded positively to zebra mussel colonisation either by remaining in sediments underlying zebra mussel colonies or by migrating into zebra mussel colonies.
Partitioning processes controlling water column phosphorus concentrations in a shallow wetland
Authors: Qiu Song , McComb Arthur J. , Bell Richard W. , Davis Jenny A. 
Published: April 2004

Summary1. Phosphorus (P) concentrations in the water column of lakes and wetlands are crucial to their trophic status and ecosystem function, but quantifying the processes controlling P concentrations in the field has been a difficult task. A site‐based, in‐lake method is described to partition major field processes controlling P concentration in a shallow lake.2. It involves (i) in‐lake deployment of a suite of chambers that isolate in‐chamber activities from atmospheric sources, groundwater input and horizontal water movement; (ii) monitoring P concentrations and relevant water properties inside and outside the isolation chambers; and (iii) calculating the contribution of each individual process by simple mathematical deduction, so as to differentiate the contributions from the different sources.3. The method was applied at nearshore and offshore sites in a seasonal, groundwater‐fed shallow lake on the Swan Coastal Plain, south‐western Australia, during winter refilling. Primary (atmospheric and groundwater) and secondary processes (e.g. circulation and sediment‐water interactions) were partitioned and quantified in terms of their contributions to water column P [as total P (TP; μg m−2 day−1)].4. Atmospheric and groundwater inputs were the two main processes contributing P loadings (1233 and 1010 μg P m−2 day−1), but their influence appeared restricted to the near‐shore site. The estimated influence on TP by mixing‐circulation, atmosphere and groundwater were 2.4–25 times higher near the lake margin as compared with the offshore site. The circulation and sediment‐water interactions decreased water column P at the marginal site, but increased P offshore because of subsequent P release from sediment and a concurrent increase in pH.5. Results are consistent with data reported elsewhere, and the factors that could affect the accuracy of partitioning are discussed.