bluuebunny/crossref_metadata_2025 huggingface dataset:
PHYSIOLOGICAL CHANGES DURING GERMINATION OF PITHOPHORA OEDOGONIA (CHLOROPHYCEAE) AKINETES1
Authors: O'Neal Steven W. , Lembi Carole A.
Published: November 2004

Akinetes of Pithophora oedogonia (Mont.) Wittrock, formed in stationary phase cultures, were induced to germinate by transfer to fresh media. Changes in various physiological parameters were monitored during the first 20 d of germination. Ungerminated akinetes contained a greater percentage of lipid, starch, and dry matter and exhibited lower photosynthetic rates than did vegetative cells. Germination consisted of four phases. Phase I (day‐0 to day‐1) was marked by a rapid increase in respiratory rates. Phase II (day‐2 to day‐6) involved protrusion of the germination tube and was insensitive to cyanide, a respiratory inhibitor, and simazine, a photosynthetic inhibitor. Phase III (day‐7 to day‐14) was marked by rapid elongation of the germination tube, increasing photosynthetic rate, increasing chlorophyll and water content and declining levels of lipid and starch. Germination tube elongation during phase III was not inhibited by simazine, but was cyanide sensitive. Phase IV (day‐15 to day‐20) was characterized by a reduction in respiratory rate and an abrupt increase in the ratio of photosynthesis to respiration. Germination tube elongation during phase IV was inhibited by simazine. The data indicate that germination in Pithophora oedogonia akinetes consists of an extensive period (phases I, II and III) during which reserve materials are respired. Utilization of internal food reserves apparently permits akinetes to germinate and supports the initial growth of the germination tube in light limited microenvironments.
WALL MORPHOGENESIS INCOSCINODISCUS WAILESIIGRAN AND ANGST. I. VALVE MORPHOLOGY AND DEVELOPMENT OF ITS ARCHITECTURE1
Authors: Schmid Anna‐Maria M. , Volcani Benjamin E.
Published: November 2004

The morphology of the valve ofCoscinodiscus wailesiiand the development of its siliceous architecture, studied in the SEM and TEM, is compared with valve formation inThalassiosira eccentrica(Ehrenberg.) Cleve. Though the areolae‐architecture of these two species differs in such that the cribrum is proximal and the foramen distal inT. eccentrica, and inC. wailesiithe cribrum is distal and the foramen proximal, the formation of their complex loculate system is similar, displacing a centrifugal growth pattern with respect to the valve, and a proximal to distal, sequentially. During base layer formation a hitherto undescribed rib system outlines the prospective areolae. The vertical differentiation is in principle the same as inT. eccentricaand also the cribra are formed centripetally in relation to the areolae in both species. The location of the cribra at the proximal or distal side, therefore, seems to be of minor importance for the sequence of silica deposition. Variation in girdle bands is discussed with respect to cell division. The prophasic nuclear migration from the interphase position to the girdle bands, where mitosis is performed, seems to be necessary for triggering the formation of the unilateral cleavage furrow that later forms a cleavage ring with excentric position. The divided nuclei migrate with the ingrowing cleavage furrow to the center of the newly created protoplasmic surfaces to initiate valve formation.
THE EFFECT OF NUTRIENT LIMITATION AND ITS INTERACTION WITH LIGHT UPON THE PRODUCTS OF PHOTOSYNTHESIS IN MERISMOPEDIA TENUISSIMA (CYANOPHYCEAE)1
Authors: Konopka Allan
Published: November 2004

The metabolic fate of photosynthetically‐fixed CO2 was determined by labeling samples of Merismopedia tenuissima Lemmerman for 30 min with NaH14CO3 and analyzing its incorporation into low molecular weight compounds, polysaccharide and protein. In N‐ and P‐sufficient cultures, relative incorporation into protein increased as the irradiance used during the labeling period was decreased to 20 μE · m‐2 s‐1. This pattern was found for cells grown at irradiances of either 20 or 180 μE · m‐2· s‐1, although incorporation into protein was greater in cultures grown at the higher irradiance. In N‐limited continuous cultures, relative incorporation into protein was low, independent of growth rate, and the same for samples tested at 20 or 180 μE · m‐2· s‐1 irradiance. In contrast, 14C incorporation into protein by P‐limited cultures increased as growth rate increased, and at relative growth rates greater than 0.25, the incorporation was greater at 20 than at 180 μE · m‐2· s‐1. However, the total RNA content and maximum photosynthetic rate of the cultures was the same at all growth rates tested. The interaction between nutrient concentration and light intensity was studied by growing‐limited continuous cultures at the same dilution rate, but different irradiances. Relative incorporation into protein was highest in cultures grown at 20 μE · m‐2· s‐1, in which the relative growth rate was 0.4. These results suggest that photosynthetic carbon metabolism may respond to relative growth rate μ/μmax rather than to growth rate directly.
VARIABILITY IN RATIOS OF PHYTOPLANKTON CARBON AND RNA TO ATP AND CHLOROPHYLL A IN BATCH AND CONTINUOUS CULTURES1,2
Authors: Laws Edward A. , Karl David M. , Redalje Donald G. , Jurick Richard S. , Winn Christopher D.
Published: November 2004

The feasibility of estimating phytoplankton carbon and RNA concentrations from measurements of ATP and chlorophyll a (chl a) concentrations was studied using chemostat populations of the marine diatom Thalassiosira weissflogii (Grunow) Fryxell & Hasle (= T. fluviatilis Hustedt). C:ATP and RNA:ATP ratios were studied for six additional marine species in batch culture representing five classes of phytoplankton. Statistical analyses revealed that both the growth rate and the factor limiting growth (NO3‐, NH4+, PO43‐ or light) could alter C:ATP, RNA: ATP, C:chl a and RNA:chl a ratios by amounts which were large compared to measurement error. An analysis of variance of the batch culture results indicated that both species and the source of inorganic nitrogen (NO3‐, or NH4+) had a significant effect on C:ATP and RNA:ATP ratios. Light had less of an influence on C:ATP and RNA:ATP ratios than on C:chl a and RNA:chl a ratios, and for this reason we feel that phytoplankton C and RNA concentrations can be estimated with greater reliability from ATP than from chl a measurements. The range of C:ATP and RNA:ATP values found for T. weissflogii under a variety of growth conditions was similar to that for the six additional species grown in batch culture, suggesting that this range of values is indicative of the extremes likely to occur in living cells. Our results and additional data in the literature indicate that phytoplankton C and RNA concentrations can be estimated to within a factor of two by multiplying ATP concentrations by 311 and 35, respectively, in N limited systems, and by 341 and 36, respectively in PO43‐ limited systems.
ELECTRON MICROSCOPIC OBSERVATIONS ON TUBULAR STRUCTURES INVOLVED IN CRYSTAL FORMATION IN THE RED ALGA PLEONOSPORIUM SQUARRULOSUM (HARV.) ABBOTT1
Authors: Kugrens Paul
Published: November 2004

Hexagonal or angular crystalline inclusions in Pleonosporium (Naeg.) Hauck vegetative cells were examined using electron microscopy. Ultrastructural analysis reveals that the inclusions initially contain tubular elements resembling microtubules but, with continued differentiation, are transformed into rod containing crystals. The tubular structures initially measure 25 nm in diameter. Scattered tubules become arranged in a parallel and alternate pattern and undergo subsequent enlargement to approximately 29 nm. Following enlargement, each tubule apparently disaggregates into rods that form a crystal having hexagonally arranged rod‐like subunits. It is suggested that these tubules may represent microtubules and the resultant crystals are composed of tubulin.
GLOEOCOCCUS TETIMSPORUS SP. NOV. (TETRASPORALES, PALM ELL ACEAE), FROM COLORADO MOUNTAIN LAKES1
Authors: Kugrens Paul
Published: November 2004

A new species, Gloeococcus tetrasporus sp. nov., collected from mountain lakes, is described from unialgal culture. Vegetative cells are ellipsoid and Chlamydomo nas–like, occur in tetrad complexes within the general colonial matrix, and exhibit slow, limited motility within the confines of the individual gelatinous matrices. The colonial matrix is amorphous and structureless, without a definite bounding layer. Colonies may reach several centimeters in size. Vegetative cells have a parietal cup–shaped chloroplast with a central–basal pyrenoid and a small, linear stigma, two contractile vacuoles, and two short flagella. Cell division is by eleutheroschisis in nonflagellate cells. After two divisions, four daughter cells arc formed within the expanded parent wall that will become incorporated into the colonial matrix. Zoospores are formed either from transformed vegetative cells or after cytokinesis. Zoospore flagella are two to three times the length of vegetative cell flagella. Rapid flagellar movement ruptures the sheath and liberates the zoospores. When zoospores settle, they secrete new sheaths, and divide twice to initiate new colonies. Sexual reproduction and formation of resistant spores were not observed.
Tax and Spending Limits in Colorado
Authors: James Franklin J. , Wallis Allan
Published: November 2004

In 1992, Colorado voters approved the Taxpayers Bill of Rights (TABOR), which severely limits the growth of revenues and spending by state and local governments. TABOR was layered over two earlier revenue‐restricting measures. Throughout the 1990s, the state enjoyed a robust economy and the effects of these restrictions were largely masked. However, government funding for several basic services in Colorado was rapidly slipping. When Colorado went into recession, the effects of these restrictions were fully felt for the first time, but neither the governor, legislature, nor policy nonprofits have been able to find a way out of the budget bind.
Tax and Expenditure Limitations and the Fiscal Response of Local Government: Asymmetric Intra‐Local Fiscal Effects
Authors: Mullins Daniel R.
Published: November 2004

This article empirically investigates the effects of introducing statewide measures to limit the ability of local jurisdictions to raise revenue or make expenditures. It does so in intervals of five years over a 25‐year period, using fiscal observations for 31,804 units of local government in 787 metropolitan counties across the contiguous United States. Specifically explored is the effect of tax and expenditure limitations on the variation in revenues and expenditures between general purpose governments and school districts within county areas. Rather than imposing a uniform constraint across jurisdictions, tax and expenditure limitations (TELs) are associated with increased variation across both general purpose and school district revenues and expenditures and, by implication, increased service differentials. Effects are found to be asymmetric, with increased variation greatest within counties comprising the urban core and those with relatively more disadvantaged populations. The implications are that TELs are most constraining on the ability of governments serving economically less prosperous and at risk populations to meet public service needs. Such differential effects are of more than questionable merit and are the result of the application of blunt instruments to what is often an undemonstrated need. The outcome impairs both the efficiency and responsiveness of the local public sector.
Sex ratio in relation to season and host plant quality in a monogenous stem‐galling midge (Diptera: Cecidomyiidae)
Authors: Dorchin Netta , Freidberg Amnon
Published: November 2004

Abstract. 1. The sex determination mechanism in gall midges is little understood, although it is known that the females of several species primarily or exclusively produce unisexual broods throughout their lifetime.

2. The gall midgeIzeniola obesulaDorchin is a multivoltine species, inducing multi‐chambered stem galls on the salt‐marsh plantSuaeda monoica. Each gall contains 5–70 individuals, all being the progeny of a single female. Sampling of more than 450 galls, from which adult midges were reared, suggested thatI. obesulaexhibits strict monogeny, resulting in galls that contain either all female or all male progeny.

3. Characterisation of the growth pattern of youngS. monoicashoots revealed that shoots in apical positions grew more rapidly than shoots in more basal positions. Galls that were induced on such shoots were larger and yielded more adult midges.

4. No difference in the site of gall induction was found between male and female galls, with galls of either sex being mainly induced on more rapidly growing shoots. It is concluded thatI. obesulafemales cannot control the sex of their progeny, and that both female‐producers and male‐producers strive to maximise their reproductive success by choosing the faster‐growing shoots for gall induction.

5. Female galls were larger and more abundant than male galls at almost all times. The sex ratio among galls fluctuated throughout the year, ranging from 4:1 in spring to 1:1 in winter. The skewed sex ratio among galls possibly results from greater mortality rates among male galls than among female galls, due to either primary or secondary factors. Alternatively, it is possible that the number or fitness of male‐producers in the population is reduced relative to female‐producers.
Butterfly habitats, broad‐scale biotope affiliations, and structural exploitation of vegetation at finer scales: the matrix revisited
Authors: Dennis Roger L. H.
Published: November 2004

Abstract. 1. Biotope and resources data are rarely attached to arthropod (butterfly) synoptic monitoring systems, and invariably not linked to behavioural exploitation of vegetation substrates. Yet, these data allow us to examine resource use within different biotopes and to distinguish more clearly between habitat and the matrix.

2. Comparative data on vegetation exploitation for different behaviours (search flight, direct flight, tactile inspections, perching, feeding, interactions, oviposition) were collected using transect sections over a range of biotopes from bare ground to mature woodland for two closely related satyrine butterflies,Maniola jurtinaandPyronia tithonuswith overlapping flight times. Occupancy data were obtained onPararge aegeriaas a marker for the woodland end of the biotope spectrum.

3. There were clear distinctions in biotope occupancy betweenM. jurtina(grassland bias) andP. tithonus(shrub bias); significant differences in exploitation of vegetation substrates (except for nectar feeding) coincided with this bias in transect sections which comprise both grassland and shrubs. The exception (nectar feeding) is explained by the decline in shrub (Rubus fruticosus) nectar and increase in herb nectar during the later emergence ofP. tithonus.

4. Direct flight increased in unsuitable biotopes for both species. However, resource‐exploiting behaviour (>70%) predominated even in biotopes that would be regarded as completely unsuitable for supporting the species and where less than 2% of individuals for each species were observed.

5. Simultaneous collection of biotope, resources, and behavioural data is needed for monitoring affinities of butterflies to vegetation structures and using butterflies as indicators of environmental changes.

6. Much of the landscape is shown to comprise valuable resources for butterflies, even when classified for metapopulation studies as empty matrix.
Ant mutualists alter the composition and attack rate of the parasitoid community for the gall waspDisholcaspis eldoradensis(Cynipidae)
Authors: Inouye Brian D. , Agrawal Anurag A.
Published: November 2004

Abstract. 1. The strength or density dependence of pairwise species interactions can depend on the presence or absence of other species, especially potential mutualists.

2. The gall waspDisholcaspis eldoradensisinduces plant galls that secrete a sweet honeydew from their top surfaces while the wasp larvae are active. These galls are actively tended by Argentine ants, which collect the honeydew and drive off parasitoids attempting to attack the gall wasp.

3. When ants were excluded, the total rate of parasitism by seven species of parasitoids increased by 36%, and the rate of gall‐wasp emergence decreased by 54%.

4. The total percentage parasitism was affected by gall density when ants were excluded but not when ants were unmanipulated, suggesting a change in parasitoid functional responses due to ant tending.

5. In addition, excluding ants significantly altered the proportions of different parasitoid species that emerged from galls; one parasitoid species increased from 1% to 34%, and another decreased from 46% to 19%.

6. The invasive Argentine ants studied are capable of maintaining the mutualism with the gall wasps that evolved in the presence of different ant species and also act as a selective filter for the local community of generalist parasitoids trying to attack this gall species.
Host selection patterns in insects breeding in bracket fungi
Authors: Jonsell Mats , Nordlander Göran
Published: November 2004

Abstract.  1. Fungivorous insects are generally viewed as polyphagous, largely because most fungal fruiting bodies constitute an unpredictable resource. To examine the validity of this hypothesis, and degree of phylogenetic relatedness between the preferred hosts of the insects, host selection in the insect fauna of bracket fungi was studied, using data obtained both from the field and the literature.

2. More than half (53%) of the insect species breeding in them appeared to be monophagous.

3. Modern phylogenies explained the host selection patterns better than older classifications, since non‐monophagous species of beetles frequently used hosts that are closely related to each other.

4. The hypothesis that polyphagous species use more heavily decayed fruiting bodies than monophagous species was verified for insects breeding in Fomes fomentarius. The results indicate that the chemical composition of the fungi influences host selection.

5. It is suggested that fruiting bodies of bracket fungi differ from most other fungi in that their occurrence is more predictable. Therefore, the primary colonising fungivores generally attack only one host species, or a few hosts that are closely phylogenetically related. Polyphagous species generally colonise fruiting bodies after they have reached a certain stage of decay, thus escaping their chemical defence.
High local species richness of parasitic wasps (Hymenoptera: Ichneumonidae; Pimplinae and Rhyssinae) from the lowland rainforests of Peruvian Amazonia
Authors: Sääksjärvi Ilari E. , Haataja Samuli , Neuvonen Seppo , Gauld Ian D. , Jussila Reijo , Salo Jukka , Burgos Andres Marmol
Published: November 2004

Abstract. 1. The parasitic wasp family Ichneumonidae (Hymenoptera) is of great interest because it has been claimed that its species richness does not increase with decreasing latitude.

2. No extensive studies of the family have been conducted in South American localities.

3. Arthropods were sampled using 27 Malaise traps in the Allpahuayo–Mishana National Reserve (56 000 ha) in the north‐eastern Peruvian Amazonian lowland rainforest. The total duration of the sampling programme was 185 Malaise trap months.

4. Altogether, 88 species were collected. This is one of the highest local pimpline and rhyssine species numbers ever recorded. A comparison with results from Mesoamerica revealed that at equal numbers of individuals sampled, the number of Pimplinae and Rhyssinae species in Peruvian Amazonia is at least twofold compared with lowland locations in Mesoamerica and somewhat higher than in the most species‐rich Costa Rican higher altitude localities.

5. Non‐parametric methods of estimating species richness were applied. These suggest that additional sampling would yield a considerable number of new Pimplinae and/or Rhyssinae species.
Effects of proteasome inhibitors MG132, ZL3VS and AdaAhx3L3VS on protein metabolism in septic rats
Authors: Kadlčíková Jana , Holeček Milan , Šafránek Roman , Tilšer Ivan , Kessler Benedikt M.
Published: November 2004

Proteasome inhibitors are novel therapeutic agents for the treatment of cancer and other severe disorders. One of the possible side effects is influencing the metabolism of proteins. The aim of our study was to evaluate the influence of three proteasome inhibitors MG132, ZL3VS and AdaAhx3L3VS on protein metabolism and leucine oxidation in incubated skeletal muscle of control and septic rats. Total proteolysis was determined according to the rates of tyrosine release into the medium during incubation. The rates of protein synthesis and leucine oxidation were measured in a medium containing L‐[1‐14C]leucine. Protein synthesis was determined as the amount of L‐[1‐14C]leucine incorporated into proteins, and leucine oxidation was evaluated according to the release of 14CO2 during incubation. Sepsis was induced in rats by means of caecal ligation and puncture. MG132 reduced proteolysis by more than 50% and protein synthesis by 10–20% in the muscles of healthy rats. In septic rats, proteasome inhibitors, except ZL3VS, decreased proteolysis in both soleus and extensor digitorum longus (EDL) muscles, although none of the inhibitors had any effect on protein synthesis. Leucine oxidation was increased by AdaAhx3L3VS in the septic EDL muscle and decreased by MG132 in intact EDL muscle. We conclude that MG132 and AdaAhx3L3VS reversed protein catabolism in septic rat muscles.
Regulation of growth signalling and cell cycle by Kaposi's sarcoma‐associated herpesvirus genes
Authors: Direkze Shamindra , Laman Heike
Published: November 2004

Kaposi's sarcoma‐associated herpesvirus (KSHV) is the primary aetiological agent of at least three malignancies associated with HIV infection and immunosuppression: Kaposi's sarcoma, primary effusion lymphoma and multicentric Castleman's disease. KSHV encodes proteins that deregulate key checkpoints in the signalling pathways governing cell proliferation, which may ultimately contribute to the virus' oncogenic potential. To alter cellular signalling associated with proliferation, these viral proteins function like growth factor ligands/receptors, signal transduction proteins, transcription factors and cell cycle regulators. This review focuses on the mechanisms by which some KSHV‐encoded proteins activate signalling pathways and cell proliferation and their role in the pathogenesis of KSHV‐driven mechanisms.
Perception of Faces and Bodies
Authors: Slaughter Virginia , Stone Valerie E. , Reed Catherine
Published: November 2004

Human faces and bodies are both complex and interesting perceptual objects, and both convey important social information. Given these similarities between faces and bodies, we can ask how similar are the visual processing mechanisms used to recognize them. It has long been argued that faces are subject to dedicated and unique perceptual processes, but until recently, relatively little research has focused on how we perceive the human body. Some recent paradigms indicate that faces and bodies are processed differently; others show similarities in face and body perception. These similarities and differences depend on the type of perceptual task and the level of processing involved. Future research should take these issues into account.
Forensic Developmental Psychology
Authors: Bruck Maggie , Ceci Stephen
Published: November 2004

We summarize recent developments in the field of forensic developmental psychology that challenge traditional conceptions about the reliability of children's reports. The areas covered involve the disclosure patterns of sexually abused children, the nature of suggestive interviews, developmental differences in suggestibility, and the amount of suggestion required to produce false reports and beliefs.
Treating Pain With Hypnosis
Authors: Patterson David R.
Published: November 2004

The use of hypnosis for pain control has a strong foundation in the experimental literature, as well as in numerous anecdotal reports. Up until the past two decades, however, there were very few controlled studies supporting its clinical efficacy. A review of the recent literature suggests that hypnosis can be effective for both acute and chronic pain. Clinicians can optimize their effectiveness by attending to both the experimental literature (e.g., increasing patients' expectations) and clinical findings (e.g., matching hypnotic suggestions to the type of pain).
The use of pharmacokinetic and pharmacodynamic data in the assessment of drug safety in early drug development
Authors: Walker D. K.
Published: November 2004

The pharmaceutical industry continues to look for ways to reduce drug candidate attrition throughout the drug discovery and development process. A significant cause of attrition is due to safety issues arising either as a result of animal toxicity testing or in the clinical programme itself. A factor in the assessment of safety during early drug development is the pharmacokinetic profile of the compound. This allows safety data to be considered in the light of systemic drug exposure and therefore permits a quantitative assessment. This is particularly applicable when assessing the risk of a new chemical entity (NCE) in relation to safety parameters such as QT interval prolongation, where free plasma concentrations have been shown to be predictive of this property in relation to potency in preclinical testing. Prior to actual human exposure it is therefore important to be able to predict reliably the pharmacokinetic behaviour of an NCE in order to place such safety findings into a quantitative risk context. The emerging science of pharmacogenetics is likely to further our ability to assess the risk of NCEs to populations and individuals due to genetic variance. The drug metabolizing enzyme CYP2D6 has been recognized as providing the potential to result in widely differing systemic drug exposure in the patient population due to polymorphic expression. Further knowledge is likely to add to our understanding of population differences in exposure and response and aid in the identification of risk factors. One potential strategy for improving the effectiveness of the drug discovery process is to obtain clinical pharmacokinetic data more rapidly in order to assess more accurately the potential for both efficacy and safety of an NCE. Whilst procedures and technologies are available that allow this on the microdose scale, it is important that we recognize potential limitations of these approaches in order that they can be applied beneficially.
Subjective and physiological responses among racemic‐methadone maintenance patients in relation to relative (S)‐ vs. (R)‐methadone exposure
Authors: Mitchell Timothy B. , Dyer Kyle R. , Newcombe David , Salter Amy , Somogyi Andrew A. , Bochner Felix , White Jason M.
Published: November 2004

Aims

To investigate the possibility that (S)‐methadone influences therapeutic and adverse responses to rac‐methadone maintenance treatment, by examining how subjective and physiological responses among rac‐methadone maintenance patients vary in relation to relative exposure to (S)‐ vs. (R)‐methadone.

Methods

Mood states (Profile of Mood States), opioid withdrawal (Methadone Symptoms Checklist), physiological responses (pupil diameter, heart rate, respiration rate, blood pressure), and plasma concentrations (CP) of (R)‐ and (S)‐methadone were measured concurrently 11–12 times over a 24‐h interdosing interval in 55 methadone maintenance patients. Average steady‐state plasma concentrations (Cav) and pharmacodynamic responses were calculated using area under the curve (AUC). Linear regression was used to determine whether variability in pharmacodynamic responses was accounted for by (S)‐methadone Cav controlling for (R)‐methadone Cav and rac‐methadone dose. Ratios of (S)‐:(R)‐methadone using AUCCP and trough values were correlated with pharmacodynamic responses for all subjects and separately for those with daily rac‐methadone doses ≥ 100 mg.

Results

(S)‐methadone Cav accounted for significant variability in pharmacodynamic responses beyond that accounted for by (R)‐methadone Cav and rac‐methadone dose, showing positive associations (partial r) with the intensity of negative mood states such as Tension (0.28), Fatigue (0.31), Confusion (0.32), and opioid withdrawal scores (0.30); an opposite pattern of relationships was evident for (R)‐methadone. The plasma (S)‐:(R)‐methadone AUCCP ratio (mean ± SD 1.05 ± 0.21, range 0.65–1.51) was not significantly related to pharmacodynamic responses for the subjects as a whole but showed significant positive associations (r) with the intensity of negative mood states such as Total Mood Disturbance (0.61), Tension (0.69), Fatigue (0.65), Confusion (0.64), Depression (0.49) and heart rate (0.59) for the ≥ 100‐mg dose range.

Conclusions

These findings agree with previous evidence that (S)‐methadone is associated with a significant and potentially adverse profile of responses distinct from that of (R)‐methadone. Individual variability in relative (S)‐ vs. (R)‐methadone exposure may be associated with variability in response to rac‐methadone maintenance treatment.
Enhancement of insulin‐stimulated myocardial glucose uptake in patients with Type 2 diabetes treated with rosiglitazone
Authors: Hällsten K. , Virtanen K. A. , Lönnqvist F. , Janatuinen T. , Turiceanu M. , Rönnemaa T. , Viikari J. , Lehtimäki T. , Knuuti J. , Nuutila P.
Published: November 2004

Aims  Peroxisome proliferator‐activated receptor γ (PPARγ) activators have recently been identified as regulators of cellular proliferation, inflammatory responses and lipid and glucose metabolism. These agents prevent coronary arteriosclerosis and improve left ventricular remodelling and function in heart failure after myocardial infarction. Improvement in myocardial metabolic state may be one of the mechanisms behind these findings. The aim of this study was to investigate the effects of rosiglitazone on myocardial glucose uptake in patients with Type 2 diabetes. Placebo and metformin were used as control treatments.

Methods  Forty‐four patients were randomized to treatment with rosiglitazone (4 mg b.i.d.), metformin (1 g b.i.d.) or placebo in a 26‐week double‐blinded trial. Myocardial glucose uptake was measured using [18F]‐2‐fluoro‐2‐deoxy‐D‐glucose ([18F]FDG) and positron emission tomography (PET) during euglycaemic hyperinsulinaemia before and after the treatment.

Results  Rosiglitazone increased insulin‐stimulated myocardial glucose uptake by 38% (from 38.7 ± 3.4 to 53.3 ± 3.6 µmol 100 g−1 min−1, P = 0.004) and whole body glucose uptake by 36% (P = 0.01), while metformin treatment had no significant effect on myocardial (40.5 ± 3.5 vs. 36.6 ± 5.2, NS) or whole body glucose uptake. Myocardial work as determined by the rate‐pressure‐product was similar between the groups. Neither treatment had any significant effect on fasting serum free fatty acids (FFA) but the FFA levels during hyperinsulinaemia were more suppressed in the rosiglitazone group (−47%, P = 0.02). Myocardial glucose uptake correlated inversely to FFA concentrations both before (r =−0.54, P = 0.002) and after (r = −0.43, P = 0.01) the treatment period in the pooled data. Furthermore, the increase in myocardial glucose uptake correlated inversely with interleukin‐6 (IL‐6) concentrations (r = −0.58, P = 0.03).

Conclusions  In addition to the improvement in whole body insulin sensitivity, rosiglitazone treatment enhances insulin stimulated myocardial glucose uptake in patients with Type 2 diabetes, most probably due to its suppression of the serum FFAs.
Aldose reductase gene polymorphisms and susceptibility to microvascular complications in Type 2 diabetes
Authors: Sivenius K. , Niskanen L. , Voutilainen‐Kaunisto R. , Laakso M. , Uusitupa M.
Published: November 2004

Aims  The gene encoding the human aldose reductase, the first and rate‐limiting enzyme of the polyol pathway of glucose metabolism, is a promising candidate gene which may contribute to diabetic microvascular complications. We investigated the association of two previously reported DNA sequence variants of this gene, the C‐106T polymorphism and the (CA)n dinucleotide repeat marker, with the risk of albuminuria and retinopathy in Finnish Type 2 diabetic patients and non‐diabetic control subjects.

Methods  The study population included 85 Finnish, middle‐aged, newly diagnosed Type 2 diabetic patients and 126 non‐diabetic control subjects. Genetic analyses were performed using the polymerase chain reaction, restriction fragment length polymorphism, and automated laser fluorescence scanning analyses. Microvascular complications were determined using 10‐year follow‐up data of urinary albumin excretion measurements and ophthalmological examinations.

Results  The C and Z‐2 alleles of the C‐106T polymorphism and the (CA)n repeat marker, respectively, were found to be more frequent in Type 2 diabetic subjects than in non‐diabetic subjects. The C and Z‐2 alleles were in 60% linkage disequilibrium in diabetic subjects. At the time of diagnosis, diabetic subjects with the T allele of the C‐106T polymorphism had significantly higher urinary albumin excretion rate and prevalence of albuminuria than subjects with the C‐106C genotype (prevalence of albuminuria: 33.3 vs. 13.8%, P = 0.036, odds ratio = 3.9, 95% confidence interval 1.1, 14.7). The Z‐2 allele of the (CA)n repeat marker was not consistently associated with the prevalence of albuminuria. No associations were observed between the polymorphisms examined and the prevalence of retinopathy at any point of the follow‐up.

Conclusions  The present study suggests that the C‐106T polymorphism of the aldose reductase gene could be involved in the early development of microalbuminuria in Finnish Type 2 diabetic patients.
Evaluation of delivery of enhanced diabetes care to patients of South Asian ethnicity: the United Kingdom Asian Diabetes Study (UKADS)
Authors: O'Hare J. P. , Raymond N. T. , Mughal S. , Dodd L. , Hanif W. , Ahmad Y. , Mishra K. , Jones A. , Kumar S. , Szczepura A. , Hillhouse E. W. , Barnett A. H. ,   on behalf of the UKADS study group
Published: November 2004

Aims  We tested the hypothesis that enhanced care for diabetes, tailored to the needs of the South Asian community with Type 2 diabetes, would improve risk factors for diabetic vascular complications and ultimately reduce morbidity and mortality.

Patients and methods  The study was a cluster randomized controlled trial (RCT) with general practice the unit of randomization. Six West Midlands general practices with a high proportion of South Asian patients were randomized to ‘enhanced care’ using Asian link workers and extra community diabetes specialist nurse sessions (intervention) or continued standard practice care (control).

Results  Of 401 patients recruited to the study, 361 (90%), comprising 178 from Coventry and 183 from Birmingham were eligible and included in the analyses. The mean age at baseline (standard deviation, SD) was 58.9 (11.7 years) with median (interquartile range; IQR) duration of diabetes 6.5 (3–11) years. At one year follow‐up there was a significant difference in reduction of systolic (4.6 mmHg, P = 0.035) and diastolic blood pressure (3.4 mmHg, P = 0.003) and total cholesterol (0.4 mmol/l, P = 0.005), comparing the intervention and control groups. After adjusting for baseline measurement and age, only differential reduction in diastolic blood pressure remained significant. There was no significant change in HbA1c and no difference between the groups.

Conclusions  Using link workers and extra community diabetes specialist nurse input together with treatment protocols in primary care might prove a useful strategy in working towards NSF targets for diabetes management. In this study, small reductions in blood pressure and cholesterol were achieved. Improvement in glycaemic control may require longer and possibly different strategies. Further research is required to evaluate fully the effectiveness, including the costs and longer term sustainability of culturally sensitive initiatives.
Autonomic response patterns observed during the performance of an attention‐demanding task in two groups of children with autistic‐type difficulties in social adjustment
Authors: Althaus Monika , Van Roon Arie M. , Mulder Lambertus J.M. , Mulder Gijsbertus , Aarnoudse Cecilia C. , Minderaa Ruud B.
Published: November 2004

Two groups of children with autistic‐type behavior problems were compared to a group of normal children with respect to their autonomic response patterns observed during the performance of an attention‐demanding task. Heart rate, blood pressure, and respiratory activity were measured during periods of rest and of task performance. Applying a quantitative model of the baroreflex, we were able to demonstratequalitativedifferences among the groups with respect to their vagally controlled response patterns, whereas sympathetic responsiveness did not differ. In terms of our model, the groups with autistic‐type behavior showed a decrease in central vagal tone during task performance, while vagal gain appeared to be unaffected or even increased. In contrast, the children in the control group showed the expected pattern of a decrease in vagal gain while vagal tone appeared to be increased. Implications of our findings are discussed in the light of Damasio's somatic marking hypothesis.
Design Optimization of the Graz Cycle Prototype Plant
Authors: Jericha Herbert , Go¨ttlich Emil , Sanz Wolfgang , Heitmeir Franz
Published: November 2004

Introduction of closed-cycle gas turbines with their capability of retaining combustion generated CO2 can offer a valuable contribution to the Kyoto goal and to future power generation. The use of well-established gas turbine technology enhanced by recent research results enables designers even today to present proposals for prototype plants. Research and development work of TTM Institute of Graz University of Technology since the 1990s has lead to the Graz cycle, a zero-emission power cycle of highest efficiency and with most positive features. In this work the design for a prototype plant based on current technology as well as cutting-edge turbomachinery is presented. The object of such a plant shall be the demonstration of operational capabilities and shall lead to the planning and design of much larger units of highest reliability and thermal efficiency.
Feasibility of Applying Active Lubrication to Reduce Vibration in Industrial Compressors
Authors: Santos Ilmar F. , Nicoletti Rodrigo , Scalabrin Alexandre
Published: November 2004

In this paper the complete set of modified Reynolds’ equations for the active lubrication is presented. The solution of such a set of equations allows the determination of stiffness and damping coefficients of actively lubricated bearings. These coefficients are not just dependent on Sommerfeld number, as it would be the case of conventional hydrodynamic bearings, but they are also dependent on the excitation frequencies and gains of the control loop. Stiffness as well as damping coefficients can be strongly influenced by the choice of the control strategy, servo valve dynamics and geometry of the orifices distributed over the sliding surface. The dynamic coefficients of tilting-pad bearings with and without active lubrication and their influence on an industrial compressor of 391 Kg, which operates with a maximum speed of 10,200 rpm, are analyzed. In the original compressor design, the bearing housings are mounted on squeeze-film dampers in order to ensure reasonable stability margins during full load condition (high maximum continuous speed). Instead of having a combination of tilting-pad bearings and squeeze-film dampers, another design solution is proposed and theoretically investigated in the present paper, i.e., using actively lubricated bearings. By choosing a suitable set of control gains, it is possible not only to increase the stability of the rotor-bearing system, but also enlarge its operational frequency range.
An Evaluation of the Effects of Water Injection on Compressor Performance
Authors: White A. J. , Meacock A. J.
Published: November 2004

The injection of water droplets into compressor inlet ducting is now commonly used as a means of boosting the output from industrial gas turbines. The chief mechanisms responsible for the increase in power are the reduction in compressor work per unit flow and the increase in mass flow rate, both of which are achieved by evaporative cooling upstream of and within the compressor. This paper examines the impact of such evaporative processes on compressor operation, focussing particular attention on cases with substantial overspray—i.e., for which significant evaporation takes place within the compressor itself, rather than in the inlet. A simple numerical method is described for the computation of wet compression processes, based on a combination of droplet evaporation and mean-line calculations. The method is applied to a “generic” compressor geometry in order to investigate the nature of the off-design behavior that results from evaporative cooling. Consideration is also given to the efficiency of the compression process, the implications for choking and stall, and the magnitude of the thermodynamic loss resulting from irreversible phase change.
Turbocharger Unstable Operation Diagnosis Using Vibroacoustic Measurements
Authors: Aretakis N. , Mathioudakis K. , Kefalakis M. , Papailiou K.
Published: November 2004

The possibility to detect unstable operating condition (stall or surge) of an automotive turbocharger using vibration or acoustic measurements is studied. An experimental study is performed, in order to acquire and analyze test data, to find out whether vibration or acoustic measurements can be correlated to aerothermodynamic operating condition. An instrumentation set allowing the definition of the operating point on the map of the compressor of the turbocharger is used. Hot wires at the compressor inlet serve as flow condition indicators and provide a clear indicator of the presence or not of instabilities, such as rotating stall or surge. Accelerometers are mounted on the casing and microphones are placed in the vicinity of the compressor casing, to measure vibration and sound emission. Data covering an extensive range of the compressor performance map have been collected and analyzed. Signal features from the different measuring instruments are discussed. Using such features, a bi-parametric criterion is established for determination of whether the compressor operates in the stable part of its performance characteristic or in the presence of unstable operation phenomena (rotating stall, surge). The possibility of generalizing the validity of observations is supported, by presenting results from testing a second turbocharger, which is shown to exhibit similar behavior.
Evaluation of Operational Performance of Gas Turbine Cogeneration Plants Using an Optimization Tool: OPS-Operation
Authors: Yokoyama Ryohei , Ito Koichi
Published: November 2004

To attain the highest performance of gas turbine cogeneration plants, it is necessary to rationally select the numbers and capacities of gas turbines and auxiliary equipment in consideration of their operational strategies corresponding to energy demands which change with season and time. It is also important to rationally select the options such as the variable heat to power by the steam injection or combined cycle, and the inlet air cooling by the ice storage combined with electric compression refrigeration or steam absorption refrigeration. The evaluation of the effects of these alternatives on the performance is an important work for designers. However, it takes much time to conduct the work thoroughly. The authors have developed an optimization tool named “OPS-Operation” to assess the operational strategies for given configurations and specifications of energy supply plants. This tool has a user-friendly interface for the functions of data registration, graphical flowsheet editing, automatic programming and optimization calculation, and graphical representation of results. In this paper, the effects of the aforementioned alternatives on the operational performance of gas turbine cogeneration plants are evaluated using the optimization tool in terms of many criteria including operational cost, energy consumption, and CO2 emission. It is demonstrated that the tool is very effective to evaluate the performance rationally, flexibly, and easily.
Interaction of Rim Seal and Annulus Flows in an Axial Flow Turbine
Authors: Cao C. , Chew J. W. , Millington P. R. , Hogg S. I.
Published: November 2004

A combined computational fluid dynamics (CFD) and experimental study of interaction of main gas path and rim sealing flow is reported. The experiments were conducted on a two stage axial turbine and included pressure measurements for the cavity formed between the stage 2 rotor disk and the upstream diaphragm for two values of the diaphragm-to-rotor axial clearance. The pressure measurements indicate that ingestion of the highly swirling annulus flow leads to increased vortex strength within the cavity. This effect is particularly strong for the larger axial clearance. Results from a number of steady and unsteady CFD models have been compared to the measured results. Good agreement between measurement and calculation for time-averaged pressures was obtained using unsteady CFD models, which predicted previously unknown unsteady flow features. This led to fast response pressure transducer measurements being made on the rig, and these confirmed the CFD prediction.
A Diagnostic Method for Heavy-Duty Diesel Engines Used in Stationary Applications
Authors: Hountalas D. T. , Kouremenos D. A. , Sideris M.
Published: November 2004

The diesel engine is used for power generation in stationary applications especially in isolated areas not connected to the main distribution network due to its relatively high efficiency, durability, and flexibility compared to alternative power sources. The diesel engine can easily follow power fluctuations. For this reason it is widely used for power generation in Islands in Greece. The diesel engine is a complex machine and requires intensive maintenance to insure proper and efficient operation. This is amplified by the interaction between the engine and the exhaust gas turbocharger. The present work describes an advanced troubleshooting method, based mainly on thermodynamics, for stationary engine monitoring and fault detection. The method is based on the processing of measured engine data using a simulation model and provides the current engine condition and its tuning. An application of the method on a slow speed diesel engine used for power generation is presented. The method is applied in the field and the results reveal the condition of the engine and its subsystems. Furthermore, proposals are made to improve engine performance. The method is most useful since it is possible to detect faults at their initial stage that may in the future result in serious problems and limit the availability of the engine.