bluuebunny/crossref_metadata_2025 huggingface dataset:
AGGLUTINATION OF THE CHLOROPHYCEAN FLAGELLATE DUNALIELLA TERTIOLECTA BY TREATMENT WITH LECTINS OR DIVALENT CATIONS AT ALKALINE pH1
Authors: Klut M. Emilia , Bisalputra Thana , Antia Naval J.
Published: November 2004

Washed cells of Dunaliella tertiolecta Butcher became immobile and agglutinated upon exposure to 100–400 μ/mL lectins in NaCl solution. The agglutinations were strongest with Limulus polyphemus agglutinin and wheat‐germ agglutinin, moderate with soybean agglutinin and weakest with Concanavalin A. All lectin‐induced agglutinations were inhibited or mitigated by the simultaneous presence of specific lectin‐binding sugars. The differential sensitivity of the alga to these lectins suggested that sialic acid and/or N‐acetyl‐D‐glucosamine might be the predominant lectin‐receptor sugars in the algal surface coat, with N‐acetyl‐D‐galactosamine likely present as a lesser component. In the absence of lectins, the divalent cations Mg2+, Ca2+ or Mn2+ also caused agglutination, but this process required an alkaline pH of at least ca. 8.6–8.9. Such cation‐induced agglutination was reversibly inhibited by the cation complexing agent EDTA as well as by lowering the pH below 8.0. SEM observations of the agglutinations revealed random flagellar attachments as well as direct body contact between agglutinated cells.
BRYOBESIA JOHANNAE, A SMALL TROPICAL REPRESENTATIVE OF THE ORDER CLADOPHORALES (CHLOROPHYCEAE)1
Authors: van den Hoek Christiaan
Published: November 2004

The small and ill‐known tropical chlorophyte, Brybesia johannae Weber‐van Bosse, is redescribed on the basis of living material from the coral reef of Curacao, Netherlands Antilles. Additional records are given from the Canary Islands. One species, B. johannae, is recognized (including, B. cylindrocarpa Howe 1920), and this probably has a wide Atlantic and Indo‐Pacific tropical distribution. Bryobesia is not related to Bryopsis and Derbesia (Caulerpales), but belongs to the Cladophorales. It appears to be a rudimentary Cladophora.
PHOSPHORUS LIMITATION AND CARBON METABOLISM IN A UNICELLULAR ALGA: INTERACTION BETWEEN GROWTH RATE AND THE MEASUREMENT OF NET AND GROSS PHOTOSYNTHESIS1
Authors: Harris Graham P. , Piccinin B. Beryl
Published: November 2004

Chlamydomonas reinhardii Dangeard was grown in continuous culture under P limitation at a range of dilution rates. Carbon uptake measurements were performed using double isotope (12C/14C) techniques and the fluxes of carbon in the light and dark were analysed over the range of growth rates. 14C uptake was shown to be equal to gross photosynthesis only at maximum relative growth rates; at low relative growth rates 14C uptake approximated net photosynthesis. The altered pattern of C uptake was found to be due to the suppression of dark respiration in the light and the release of 14C02 from respiratory pathways at low relative growth rates. Metabolic channelling of 14C from photosynthetic pathways to respiratory pathways occurred at low growth rates as the specific activity of the respired CO2 reached 45% of the input gas mixture. These data are discussed in the light of the controversy concerning the measurement of gross and net photosynthesis in natural populations and in the light of models of 14C uptake in single celled algae. Existing models are shown to be adequate for high relative growth rates but not for low relative growth rates under P limitation.
GROWTH, YIELD AND MORPHOLOGY OF ASCOPHYLLUM NODOSUM (PHAEOPHYTA) UNDER CONTINUOUS AND INTERMITTENT SEAWATER SPRAY CULTURE REGIMENS1
Authors: Rheault Robert B. , Ryther John H.
Published: November 2004

Growth and yield of the brown alga Ascophyllum nodosum (Le Jolis) were measured under various regimens of seawater spray culture. One‐hour periods of desiccation throughout the day and night and cessation of spray throughout the night did not affect growth relative to that in continuous spray. Desiccation for four hours during the day resulted in death. Changes in morphology from the normal intertidal growth form to that resulting from spray culture are described.
A SUSPECTED CASE OF MYCOPHYCOBIOSIS BETWEEN MYCOSPHAERELLA APOPHLAEAE (ASCOMYCETES) AND APOPHLAEA SPP. (RHODOPHYTA)1
Authors: Kohlmeyer Jan , Hawkes Michael W.
Published: November 2004

Apophlaea lyallii Hooker f. et Harvey and A. sinclairii Harvey in Hooker et Harvey, endemic Rhodophyta from New Zealand, were found to harbor a systemic fungus, Mycosphaerella apophlaeae Kohlmeyer. The algae occur on rocks in the upper intertidal zone and are resistant to desiccation and insolation. These suspected symbiotic associations which are similar to, but different from, lichens, are considered mycophycobioses. This is the first report of a supposed mycophycobiosis in members of the Rhodophyta.
THE LIPID COMPOSITION OF THORACOSPHAERA HEIMII: EVIDENCE FOR INCLUSION IN THE DINOPHYCEAE1
Authors: Jones Gary J. , Nichols Peter D. , Johns R. B.
Published: November 2004

The fatty acid, sterol and chlorophyll composition of the calcified, unicellular alga Thoracosphaera heimii (Lohmann) Kamptner are reported. The presence of 4,23,24‐termethyl‐5α‐cholest‐22E‐en‐3β‐ol (dinosterol), 4,23,24‐trimethyl‐5α‐cholest‐22E‐en‐3‐one (dinosterone) and the predominance of C18, C20 and C22 unsaturated fatty acids, including the acid 18:5ω3, indicates that T. heimii is a dinoflagellate. The fatty acid: sterol ratio (1.3), is typical of dinoflagellates. The geochemical significance of dinosterone, the high relative concentration of 4‐desmethyl‐5α‐stanols and the role of 23‐methyl‐5α‐cholest‐22E‐en‐3β‐ol in the biosynthesis of dinosterol in T. heimii are also discussed.
PHOTOSYNTHETIC QUANTUM EFFICIENCIES OF PHYTOPLANKTON FROM PERENNIALLY ICE COVERED ANTARCTIC LAKES1
Authors: Seaburg Kenneth G. , Kaspar Mark , Parker Bruce C.
Published: November 2004

A recently introduced approach far estimating the photosynthetic quantum efficiency (φ) of a freshwater or marine phytoplankton community has been applied for the first time to high latitude polar ecosystems, namely four lakes of southern Victoria Land, Antarctica. Values for φ at various depths ranged from 0.0022–0.1560 when calculated using a recommended mean extinction coefficient for phytoplankton (i.e. k̄c= 0.016). By contrast, φ ranged from 0.0037–0.0760 when calculated using an empirically estimated value for k̄c of 0.0328. If the recommended k̄c= 0.016 more closely approaches an accurate estimate, then the φ valves indicate that the phytoplankton convert light to organic carbon more efficiently than elsewhere. However, if the empirically derived k̄c= 0.0328 more closely approaches an accurate estimate, then the φ values indicate the phytoplankton trap light more efficiently than elsewhere. Although we have not resolved whether light conversion (φ) or light trapping are more efficient, the results show that the phytoplankton of these Antarctic lakes are well adapted to performing photosynthesis under extremely low light conditions.
REGULATION OF A GLUCOSE TRANSPORT SYSTEM INSTICHOCOCCUS BACILLARIS1
Authors: Carthew Richard W. , Hellebust Johan A.
Published: November 2004

Glucose and related non‐metabolizable analogs were transported into cells ofStichococcus bacillarisNaeg. By a specific and active transport system. Glucose transport capacity was stimulated eight‐fold by incubation in medium of low osmotic potential (0.09 osM). Stimulation occurred over 24 h in the dark and over 72 h in low osmotic medium. Inhibition of protein synthesis prevented any transport, stimulation from occurring. Kinetic studies revealed that the stimulation caused an increase in Ike maximal velocity of transport and did not affect the half‐saturation constant for transport. It was concluded that incubation of cells in the dark or in low osmolar medium induces a synthesis of the transport system. The glucose analog 2‐deoxy‐D‐glucose was only phosphorylated to a limited extent upon entry into the cells, and the free sugar accumulated linearly in dark pre‐incubated tells for a period of at least six minutes to reach an intracellular/extracellular concentration ratio of almost 300. Glucose, in contrast, was rapid h converted to sucrose and other cell constituents. Cells incubated 24 h with, glucose or 6‐deoxy‐D‐glucose did not exhibit any altered transport system activity. Cells incubated 24 h with 7 mM dibutyryl cAMP exhibited a 2.5‐fold stimulation of transport activity. No stimulation was observed in cells treated only 30 min with dibutyryl cAMP.
EFFECTS OF PHOTOCYCLES AND PERIODIC AMMONIUM SUPPLY ON THREE MARINE PHYTOPLANKTON SPECIES. I. CELL DIVISION PATTERNS1
Authors: OlsonM Robert J. , Chisholm Sallie W.
Published: November 2004

Cell division patterns in Thalassiosira weissflogii (Grun.), Hymenomonas carterae (Braarud and Fagerl), and Amphidinium carteri (Hulburl) grown in cyclostat culture were analyzed as functions of the periodic supply of light and the limiting nutrient (ammonium) and of combinations of these two factors. In all three species, division patterns were phased by light/dark cycles in N–limited as well as N–replte conditions, and also to ammonium pulses in N–limited growth in continuous light. Both the degree and timing of the cell cycle phasing varied among species. When both stimuli were present, the influence of the photocycle overrode the N–pulse stimulus in H. carterae and A. carteri. while in T. weissflogii, division was always phased by the timing of the N–pulse regardless of the phase angle between the photocycle and the pulse.
EFFECTS OF PHOTOCYCLES AND PERIODIC AMMONIUM SUPPLY ON THREE MARINE PHYTOPLANKTON SPECIES. II. AMMONIUM UPTAKE AND ASSIMILATION1
Authors: Wheeler Patricia A. , Olson Robert J. , Chisholm Sallie W.
Published: November 2004

The relative influence of the photoperiod and of periodic ammonium pulses in entraining the cell division cycle in nitrogen‐limited cyclostat cultures differs dramatically in Hymenomonas carterae Braarud and Fagerl, Amphidinium carteri Hulburt and Thalassiosira weissflogii Grun. We examined how each species processes an NH4+ pulse at various times during the cell cycle and the L/D cycle. Rates of NH4+ uptake and changes in cellular concentrations of NH4+, free amino acids, and protein were examined after the addition of an NH4+ pulse. Depletion of NH4+ from the medium occurred earlier when the pulse was given at the beginning of the light period than at the beginning of the dark period in H. carterae and A. carteri. Depletion took longer in the T. weissflogii cultures and the kinetics were similar during both stages of the photocycle in this species. Similarly, the temporal phasing and maximum pool sizes varied with timing of the NH4+ pulse in H. carterae and A. carteri but complete assimilation was relatively rapid. More persistent pools of NH4+ and free amino acids accumulated in T. weissflogii, and the patterns of assimilation varied little as a function of the timing of the pulse with respect to the photocycle. Although nitrogen metabolism occurred rapidly in nitrogen‐limited H. carterae and A. carteri, the entrainment of the cell division cycle by the photoperiod resulted in a large degree of uncoupling between completion of nitrogen assimilation and cell division. It is hypothesized that the strong entrainment of the cell division cycle of T. weissflogii by NH4+ pulses results from a relatively slow rate of nitrogen metabolism.
The Tax Revolt in Massachusetts: Revolution and Reason
Authors: Wallin Bruce A.
Published: November 2004

The modern‐day tax revolt in Massachusetts was initiated by passage of the property tax limitation measure Proposition 2½ in 1980. Predictions of draconian budget cuts never materialized due to state legislative modification of the initiative's provisions, and judicious use of local voter overrides. Massachusetts citizens have continued to bring tax issues to the ballot, with fairly reasoned outcomes.
The role of tumour necrosis factor‐α in renal dysfunction following mild haemorrhage in rats
Authors: Sato Hiroaki , Tanaka Toshiko , Kita Toshiro , Yamaguchi Hiroki , Tanaka Noriyuki
Published: November 2004

Mild haemorrhage occasionally causes delayed death following failure of kidney or multiple organs, but the precise mechanisms have not yet been identified. We investigated the role of tumour necrosis factor‐α (TNF‐α), known as a major pro‐inflammatory cytokine that leads to multiple organ failure, on the renal damage induced by mild haemorrhage. A mild haemorrhagic state was induced in male anaesthetized rats by bleeding via a common carotid catheter for 20 min at 16.7% of total body blood, 1.09 ml/100 g body weight, without fluid resuscitation. Mean arterial pressure and heart rate decreased soon after haemorrhaging but returned to baseline level up to 5 h after bleeding. TNF‐α mRNA expression in the kidney and serum TNF‐α levels were highest at 1 h after bleeding. Intraperitoneal pretreatment with FR167653, an inhibitory compound of TNF‐α production, as well as of interleukin (IL)‐1β, significantly inhibited the increase in TNF‐α. The inflammatory cell infiltration and tubular cell injury induced by haemorrhage were suppressed, and the renal dysfunction was dramatically improved by the FR167653 treatment. The morphological changes were also less in the treated group than in those that had not been treated. TNF‐α has been reported to have striking effects on IL‐1β release and activation of neutrophils, and to play a pivotal role in the expression of the other pro‐inflammatory cytokines. Our data show that endogenously‐derived TNF‐α does play a key role in the renal dysfunction during mild haemorrhage. These results should be useful to forensic pathologists to explain the pathogenesis of renal dysfunction induced by a mild haemorrhage and to identify the cause of death where there are no significant morphological changes after mild haemorrhage.
Vascular endothelial growth factor reduces mural cell coverage of endothelial cells and induces sprouting rather than luminal division in an HT1080 tumour angiogenesis model
Authors: Fujimoto Akihisa , Onodera Hisashi , Mori Akira , Isobe Naoki , Yasuda Seiichi , Oe Hideaki , Yonenaga Yoshikuni , Tachibana Tsuyoshi , Imamura Masayuki
Published: November 2004

Vascular endothelial growth factor (VEGF) plays a central role in tumour angiogenesis. In a mouse intramuscular tumour model using VEGF‐transfected HT1080 human fibrosarcoma, we investigated the morphological features and patterns of remodelling in size‐matched tumours. Compared with the control tumours (C group), the VEGF‐transfected tumours (V group) showed vigorous neovascularization with larger vessels. Fenestrations and disruptions of endothelia were specific to the V group. Three types of vascular remodelling, i.e. sprouting, luminal division and intussusceptive microvascular growth, were present in both groups. Morphometric analyses revealed that mural cell coverage of the endothelial cells was significantly smaller in the V group compared with that in the C group (V group, 28.2 ± 18.6%; C group, 41.6 ± 21.1%; P < 0.0001). To determine the prevalence of remodelling patterns, the occurrences of abluminal and luminal processes on endothelial cell surfaces were quantified. Abluminal processes are defined as cytoplasmic protrusions of the abluminal membrane of endothelial cells, which can vary from tiny spurs to solid sprouts of the cell. On the other hand, luminal processes are defined as intraluminal protrusions of the endothelial cell membrane, including various membranous changes from filiform processes to rather thick cytoplasmic bulges. An abluminal process is thought to represent an initial morphological change in sprouting type angiogenesis, and a luminal process to be a sign of implementation of luminal division. The frequency of abluminal processes was significantly higher in the V group than in the C group (V group, 0.243 ± 0.138/µm; C group, 0.114 ± 0.101/µm; P < 0.0001). In contrast, the number of luminal processes on the endothelial cells per micrometre was statistically comparable between the groups (V group, 0.285 ± 0.252/µm; C group, 0.309 ± 0.236/µm, P = 0.381). These results indicate that sprouting is the main mode of VEGF‐induced tumour angiogenesis.
The Role of Social Interaction in Bird Song Learning
Authors: Beecher Michael D. , Burt John M.
Published: November 2004

Bird song learning has become a powerful model system for studying learning because of its parallels with human speech learning, recent advances in understanding of its neurobiological basis, and the strong tradition of studying song learning in both the laboratory and the field. Most of the findings and concepts in the field derive from the tape-tutor experimental paradigm, in which the young bird is tutored by tape-recorded song delivered by a loudspeaker in an isolation chamber. This paradigm provides rigorous experimental control of auditory parameters, but strips song learning of any social context, and has slowed the realization that social factors might be critical to the process. In recent years, field research and lab studies using live birds as tutors have revealed that social factors play a preeminent role in song learning. In this article, we propose a new experimental paradigm—the virtual-tutor design, which permits precise manipulation of singing interactions between simulated tutors that the young bird “overhears,” as well as direct singing interactions between the young bird and the simulated tutors. We suggest that this approach may permit researchers to analyze social factors in bird song learning, particularly those relating to auditory interactions, that have been difficult to analyze heretofore.
Relationships, Human Behavior, and Psychological Science
Authors: Reis Harry T. , Collins W. Andrew
Published: November 2004

Extensive evidence attests to the importance of relationships for human well-being, and evolutionary theorizing has increasingly recognized the adaptive significance of relationships. Psychological science, however, has barely begun to consider how relationships influence a broad array of basic social, cognitive, emotional, and behavioral processes. This article discusses contemporary theory and research about the impact of relationship contexts, citing examples from research on social cognition, emotion, and human development. We propose that the validity and usefulness of psychological science will be enhanced by better integration of relationship contexts into theories and research.
The Concept of Organizational Citizenship
Authors: Borman Walter C.
Published: November 2004

This article describes the construct of citizenship performance and summarizes some of the industrial-organizational psychology research on organizational citizenship. Citizenship performance is defined as behaviors that go beyond task performance and technical proficiency, instead supporting the organizational, social, and psychological context that serves as the critical catalyst for tasks to be accomplished. The research reviewed addresses these topics: (a) the weights supervisors place on task and citizenship performance when making judgments about organization members' overall performance; (b) whether personality predicts citizenship performance better than task performance; (c) links between citizenship performance and organizational effectiveness; and (d) relations between organizational characteristics such as justice in the workplace and citizenship performance. Citizenship on the part of organization members is important in contemporary organizations. Because of current trends, such as increased global competition, greater use of teams, continuing downsizing initiatives, and more emphasis on customer service, citizenship performance is likely to be important in the foreseeable future, as well.
The Déjà Vu Illusion
Authors: Brown Alan S.
Published: November 2004

The déjà vu illusion occurs when a person has an inappropriate feeling of familiarity in a situation that is objectively unfamiliar or new. The amorphous nature of this experience has made identifying its etiology challenging, but recent advances in neurology and understanding of implicit memory and attention are helping to clarify this cognitive illusion. More specifically, déjà vu may result from (a) a brief change in normal neural transmission speed causing a slightly longer separation between identical messages received from two separate pathways, (b) a brief split in a continuous perceptual experience that is caused by distractions (external or internal) and gives the impression of two separate perceptual events, and (c) the activation of implicit familiarity for some portion (or all) of the present experience without an accompanying conscious recollection of the prior encounter. Procedures that involve degraded or occluded stimulus presentation, divided attention, subliminal mere exposure, and hypnosis may prove especially useful in elucidating this enigmatic cognitive illusion.
Current approaches to prevent NSAID‐induced gastropathy – COX selectivity and beyond
Authors: Becker Jan C. , Domschke Wolfram , Pohle Thorsten
Published: November 2004

Gastrointestinal (GI) toxicity associated with nonsteroidal anti‐inflammatory drugs (NSAIDs) is still an important medical and socio‐economic problem – despite recent pharmaceutical advances. To prevent NSAID‐induced gastropathy, three strategies are followed in clinical routine: (i) coprescription of a gastroprotective drug, (ii) use of selective COX‐2 inhibitors, and (iii) eradication of Helicobacter pylori. Proton pump inhibitors are the comedication of choice as they effectively reduce gastrointestinal adverse events of NSAIDs and are safe even in long‐term use. Co‐medication with vitamin C has only been little studied in the prevention of NSAID‐induced gastropathy. Apart from scavenging free radicals it is able to induce haeme‐oxgenase 1 in gastric cells, a protective enzyme with antioxidant and vasodilative properties. Final results of the celecoxib outcome study (CLASS study) attenuated the initial enthusiasm about the GI safety of selective COX‐2 inhibitors, especially in patients concomitantly taking aspirin for cardiovascular prophylaxis. Helicobacter pylori increases the risk for ulcers particularly in NSAID‐naive patients and therefore eradication is recommended prior to long‐term NSAID therapy at least in patients at high risk. New classes of COX‐inhibitors are currently evaluated in clinical studies with very promising results: NSAIDs combined with a nitric oxide releasing moiety (NO‐NSAID) and dual inhibitors of COX and 5‐LOX. These drugs offer extended anti‐inflammatory potency while sparing gastric mucosa.
A simple method for measuring tiller volume of grasses
Authors: Sbrissia A. F. , Da Silva S. C. , Molan L. K. , Sarmento D. O. L. , Andrade F. M. E. , Lupinacci A. V. , Gonçalves A. C.
Published: November 2004

A simple method for measuring tiller volume of grasses is described. The equipment, based on the communicant pipe principle, was built using a PVC pipe linked to a laboratory volumetric pipette. The results showed a high degree of consistency and were similar to empirical results published in the literature, indicating that tiller volume of grasses can be easily measured with this technique.
Changes during growth in the nutritive value of components of berseem clover (Trifolium alexandrinum L.) under different cutting treatments in a Mediterranean region
Authors: De Santis G. , Iannucci A. , Dantone D. , Chiaravalle E.
Published: November 2004

The nutritive value of berseem clover (Trifolium alexandrinum L.) may be influenced by changes in the nutrient concentrations of morphological fractions as a consequence of cutting treatment. The aim of this study was to evaluate the effects of different cutting treatments on the nutritive value of herbage and leaf and stem components in two Mediterranean berseem genotypes during growth in order to develop management approaches for harvesting forage with a high nutritive value. Spring growth of genotypes of Egyptian (cv. Giza 10) and Italian (cv. Sacromonte) origins was harvested in each of 2 years beginning 196 days after sowing and thereafter every 6 days (twelve harvests in total) to measure dry matter (DM) yield and nutritive value. Cutting treatments were initiated at sixth internode elongation (A) and early flowering (B) and there was an uncut control treatment (C). In vitro digestibility of organic matter (IVOMD) and crude protein (CP) concentration were determined for leaf, stem and total forage of each cultivar at each harvest. For both cultivars, in the uncut treatment (C), DM yield increased linearly to a maximum of 14 800 kg ha−1, on average, by 250 days after planting, the same time at which stem DM accumulation peaked, whereas the nutritive value, in terms of IVOMD and CP concentration, declined with age, coinciding with a reduction in leaf:stem ratio (LSR) from 1·00 to 0·30. Plant parts differed (P < 0·01) in nutritive value with stems being of lower nutritive value than leaves, in the two cutting treatments. There were strong positive correlations between LSR and herbage IVOMD and CP concentration, in both cutting treatments, indicating that, during growth, part of the changes in IVOMD and CP concentration of berseem clover plants was due primarily to the changes in the LSR. Defoliation induced a considerable reduction in DM yield, but an increase in the LSR and a small increase in nutritive value. Plants cut at the sixth internode elongation (A) showed a small proportional decrease (0·19) in total DM yield, but higher LSR values and similar or higher IVOMD and CP concentration than initiating cutting at early flower (B). Delaying defoliation to the early flowering stage (B) increased the proportion of stems and, therefore, decreased nutritive value. Therefore, harvest management in which cuts are applied at the stage of sixth internode elongation appears to be the most favourable for obtaining relatively high yields of forage with high nutritive value in berseem clover grown in Mediterranean regions.
Genetic diversity of Indian native cattle breeds as analysed with 20 microsatellite loci
Authors: Mukesh M. , Sodhi M. , Bhatia S. , Mishra B. P.
Published: November 2004

The aim of the present study was to assess the genetic variation and establish the relationship amongst the three Indian zebu cattle breeds using 20 bovine‐specific microsatellite markers. A total of 136 unrelated DNA samples from Sahiwal (SC), Hariana (HC) and Deoni (DC) breeds of cattle were genotyped to estimate within and between breed genetic diversity indices. The estimated mean allelic diversity was 5.2, 6.5 and 5.9 in SC, HC and DC, respectively, with a total of 167 alleles. The average observed and expected heterozygosity for the population varied from 0.42 (SC) to 0.59 (DC), and from 0.61 (SC) to 0.70 (DC), respectively. Low values of genetic variability estimates were observed in SC when compared with DC and HC, indicating some loss of variability because of its relatively small population size. From global F‐statistics a significant deficit of heterozygotes of 24.2% (p < 0.05) was observed for each one of the analysed breeds whereas the total population had a 32.8% (p < 0.05) deficit of heterozygotes. The FST estimates demonstrated that approximately 88.7% of the total genetic variation was because of the genetic differentiation within each breed. Pair‐wise breed differentiation, Nei's standard and DA genetic distance estimates revealed relatively close genetic similarity between HC and DC in comparison with SC. In the UPGMA‐based phylogenetic tree constructed from the genetic distances, HC and DC were grouped together in one cluster and SC in the other. The estimated time of divergence suggested a separation time of approximately 776 years between DC and HC, and a comparatively longer period (1296 years) between DC and SC.
Intravenous drug abuse and Type 1 diabetes: financial and healthcare implications
Authors: Saunders S. A. , Democratis J. , Martin J. , Macfarlane I. A.
Published: November 2004

Aims  To determine the morbidity, mortality and healthcare costs of intravenous drug‐abusing patients with Type 1 diabetes (IVDA‐DM), who are admitted to hospital.

Methods  Retrospective case note analysis of admissions, complications and cost estimation over a 6‐year period. Each drug‐abusing patient (IVDA‐DM) (n = 9) was compared with two controls (n = 18) with Type 1 diabetes but without a history of intravenous drug abuse (DM‐controls). Admissions were also analysed for patients with intravenous drug abuse, but without Type 1 diabetes (IVDA‐controls) (n = 198). Admissions were at a University teaching hospital in Liverpool, UK. DM‐controls were drawn from a population attending diabetes outpatient clinics between 1997 and 2002 at the same hospital. The main outcome measures were: the duration and healthcare costs of hospital admissions per year, outpatient attendances per year, glycated haemoglobin (HbA1c), weight, micro‐ and macrovascular complications and mortality.

Results  Multiple admissions, mainly related to ketoacidosis, led to marked differences in mean (95% CI) inpatient days per year per patient [IVDA‐DM 28.1 (13.6–42.7) vs. DM‐control 1.1 (0.2–1.9); P < 0.0001], mean inpatient days per year per patient in critical care bed (IVDA‐DM 1.7 (−0.7–4.2) vs. DM‐control 0; P < 0.02) and mean costs of admission, per patient per year (£7320 vs. £230). The IVDA‐DM group frequently omitted insulin, were underweight, failed to attend as outpatients and five had died by the end of 2002. The IVDA‐controls spent considerably less time in hospital [3.4 (2.8–3.9) days per patient per year].

Conclusion  IVDA‐DM patients have higher rates of diabetes complications, are admitted more frequently and have a high mortality compared with DM and IVDA‐controls. The cost of inpatient care of this small group of patients was considerable.
Changing aspirin use in patients with Type 2 diabetes in the UKPDS
Authors: Cull C. A. , Neil H. A. W. , Holman R. R.
Published: November 2004

Aims  To examine the proportion of UK Prospective Diabetes Study (UKPDS) patients with Type 2 diabetes taking aspirin regularly for the primary and secondary prevention of cardiovascular disease (CVD) before and after publication of the 1997 American Diabetes Association (ADA) Clinical Practice Recommendations and the 1998 Joint British Recommendations on the Prevention of Coronary Disease in Clinical Practice.

Methods  UKPDS annual review data from 1996/7 (n = 3190) and 2000/1 (n = 2467) were used to determine the prevalence of patients taking aspirin regularly in relation to known CVD risk factors and pre‐existing CVD.

Results  Patients taking aspirin regularly were more often male than female (24 vs. 20%, P = 0.0033), older (66 ± 8 vs. 62 ± 9 years, P < 0.0001) and less often Afro‐Caribbean than White Caucasian or Indian Asian (11 vs. 23 vs. 22%, respectively, P < 0.0001). Between 1996/7 and 2000/1 aspirin use in patients without pre‐existing CVD increased from 17 to 31% (P < 0.0001) and for those with pre‐existing CVD from 76 to 82% (P = 0.032).

Conclusion  The majority of patients with pre‐existing CVD were taking aspirin regularly. Although aspirin use in those without pre‐existing CVD approximately doubled after publication of the ADA and Joint British Recommendations, less than two‐thirds of these high‐risk patients were being treated according to guidelines. This may relate to a lack of convincing evidence for primary CVD prevention or failure to adhere to guidelines. It may be that more trial data is needed to convince clinicians of the value of aspirin therapy in Type 2 diabetes.
Aqueous levels of macrophage migration inhibitory factor and monocyte chemotactic protein‐1 in patients with diabetic retinopathy
Authors: Tashimo A. , Mitamura Y. , Nagai S. , Nakamura Y. , Ohtsuka K. , Mizue Y. , Nishihira J.
Published: November 2004

Aims  To investigate the relationship of aqueous macrophage migration inhibitory factor (MIF) and monocyte chemotactic protein‐1 (MCP‐1) levels with the clinical stage of diabetic retinopathy.

Methods  We assayed MIF and MCP‐1 levels in aqueous humour samples obtained from 40 diabetic patients (49 eyes) and 24 non‐diabetic patients (31 eyes) using enzyme‐linked immunosorbent assay. According to the clinical stage of diabetic retinopathy, the diabetic patients were classified into non‐diabetic retinopathy (11 eyes), non‐proliferative diabetic retinopathy (14 eyes) and proliferative diabetic retinopathy (24 eyes).

Results  The aqueous levels of MIF (mean ± sd) were 6.34 ± 4.53 ng/ml in proliferative diabetic retinopathy, 3.22 ± 1.71 ng/ml in non proliferative diabetic retinopathy, 1.25 ± 0.96 ng/ml in non‐diabetic retinopathy and 1.07 ± 0.94 ng/ml in non‐diabetic patients. Significant differences were found among these four groups (P < 0.0001). Aqueous MCP‐1 levels were 1668.6 ± 1442.3 pg/ml in proliferative diabetic retinopathy, 1528.6 ± 1994.6 pg/ml in non‐proliferative diabetic retinopathy, 690.2 ± 402.1 pg/ml in non‐diabetic retinopathy and 622.7 ± 245.3 pg/ml in non‐diabetic patients. Significant differences were also found among these four groups (P < 0.0001). After correcting for total aqueous protein, the ratios of MIF and MCP‐1 to total protein remained significantly correlated with the clinical stage of diabetic retinopathy (P < 0.0001, P = 0.0004, respectively). The ratios of MIF to total protein significantly correlated with the ratios of MCP‐1 to total protein in diabetic patients (r = 0.680, P < 0.0001).

Conclusions  Aqueous MIF levels significantly correlated with aqueous MCP‐1 levels and the clinical stage of diabetic retinopathy. The results suggest that MIF has a co‐operative role with MCP‐1 in the progression of diabetic retinopathy.
Persistent poor glycaemic control in adult Type 1 diabetes. A closer look at the problem
Authors: DeVries J. H. , Snoek F. J. , Heine R. J.
Published: November 2004

Around 25% of the adult Type 1 diabetes population is in persistent poor glycaemic control and thus at increased risk of developing microvascular complications. We here discuss correlates of long‐standing poor glycaemic control and review the efficacy of clinical strategies designed to overcome persistent poor control. Only a few studies have identified determinants and correlates of long‐standing poor glycaemic control in Type 1 diabetes. There is some evidence implicating genetic factors, as well as lower economic status, and psychological factors, including lack of motivation, emotional distress, depression and eating disorders. Ways of improving glycaemic control include strategies to enable self‐management, e.g. motivational strategies, coping‐orientated education, psychosocial therapies, and/or intensifying insulin injection therapy plus continuous subcutaneous insulin infusion. Long‐standing poor glycaemic control appears to be a heterogeneous and complex phenomenon, for which there is no simple, single solution. Comprehensive psycho‐medical assessment in diabetes care may prove useful in tailoring interventions. Further research is warranted, to increase our understanding how psychosocial and biomedical factors, separately and in interaction, determine poor outcomes in Type 1 diabetes.
Effects of arousal and natural baroreceptor activation on the human muscle stretch reflex
Authors: McIntyre David , Ring Christopher , Carroll Douglas
Published: November 2004

The nociceptive flexion reflex is inhibited during systole; this inhibition may be due to increased baroreceptor stimulation. It is yet to be determined whether other spinal reflexes are similarly modulated across the cardiac cycle. There is also evidence that stretch and tendon reflexes are facilitated by increased arousal. This study investigated the effects of phase of the cardiac cycle and arousal on the muscle stretch reflex components M1, M2, and M3. Stretch reflexes were elicited in leg muscles at six intervals across the cardiac cycle during rest, number repetition, and mental arithmetic. Mental arithmetic provoked increased cardiovascular arousal and facilitated both M1 and M2 compared to rest and number repetition. The stretch reflex did not vary with the phase of the cardiac cycle. While the stretch reflex is susceptible to arousal, natural baroreceptor‐mediated modulation across the cardiac cycle may be specific to nociception.
Detection of synchronized oscillations in the electroencephalogram: An evaluation of methods
Authors: Yeung Nick , Bogacz Rafal , Holroyd Clay B. , Cohen Jonathan D.
Published: November 2004

The signal averaging approach typically used in ERP research assumes that peaks in ERP waveforms reflect neural activity that is uncorrelated with activity in the ongoing EEG. However, this assumption has been challenged by research suggesting that ERP peaks reflect event‐related synchronization of ongoing EEG oscillations. In this study, we investigated the validity of a set of methods that have been used to demonstrate that particular ERP peaks result from synchronized EEG oscillations. We simulated epochs of EEG data by superimposing phasic peaks on noise characterized by the power spectrum of the EEG. When applied to the simulated data, the methods in question produced results that have previously been interpreted as evidence of synchronized oscillations, even though no such synchrony was present. These findings suggest that proposed analysis methods may not effectively disambiguate competing views of ERP generation.
Long‐term exposure to noise impairs cortical sound processing and attention control
Authors: Kujala Teija , Shtyrov Yury , Winkler Istvan , Saher Marieke , Tervaniemi Mari , Sallinen Mikael , Teder‐Sälejärvi Wolfgang , Alho Kimmo , Reinikainen Kalevi , Näätänen Risto
Published: November 2004

Long‐term exposure to noise impairs human health, causing pathological changes in the inner ear as well as other anatomical and physiological deficits. Numerous individuals are daily exposed to excessive noise. However, there is a lack of systematic research on the effects of noise on cortical function. Here we report data showing that long‐term exposure to noise has a persistent effect on central auditory processing and leads to concurrent behavioral deficits. We found that speech‐sound discrimination was impaired in noise‐exposed individuals, as indicated by behavioral responses and the mismatch negativity brain response. Furthermore, irrelevant sounds increased the distractibility of the noise‐exposed subjects, which was shown by increased interference in task performance and aberrant brain responses. These results demonstrate that long‐term exposure to noise has long‐lasting detrimental effects on central auditory processing and attention control.
Probing the psychophysiology of the airways: Physical activity, experienced emotion, and facially expressed emotion
Authors: Ritz Thomas
Published: November 2004

This article reviews research on airway reactivity in health and asthma within a psychophysiological context, including the effects of physical activity, emotion induction, and manipulation of facial expression of emotion. Skeletal muscle activation leads to airway dilation, with vagal withdrawal being the most likely mechanism. Emotional arousal, in particular negative affect, leads to airway constriction, with evidence for a vagal pathway in depressive states and ventilatory contributions in positive affect. Laboratory‐induced airway responses covary with reports of emotion‐induced asthma and with lung function decline during negative mood in the field. Like physical activity, facial expression of emotion leads to airway dilation. However, these effects are small and less consistent in posed emotional expressions. The mechanisms of emotion‐induced airway responses and potential benefits of emotional expression in asthma deserve further study.
Cognitive performance and cerebral blood flow in essential hypotension
Authors: Duschek Stefan , Schandry Rainer
Published: November 2004

In the present study cerebral blood flow was assessed in 40 subjects with chronically low blood pressure and 40 normotensive controls at resting conditions and during the execution of a cued reaction time task. Blood flow velocities were recorded by means of transcranial Doppler sonography in both middle cerebral arteries. In hypotensives flow velocity at rest was reduced bilaterally. During the anticipation of the stimuli, which the subjects had to respond to, a predominantly right hemispheric increase of flow velocity was observed in both groups. This increase was significantly less pronounced in the hypotensive group. Hypotensives showed longer reaction times, and there was a negative correlation between the extent of the flow velocity increase and the reaction times. This study is the first to demonstrate a reduced cerebral perfusion and maladaption of blood flow to cognitive demands due to essential hypotension.
Utilization of continuous renal replacement therapy in a case of feline acute renal failure
Authors: Landerville Andrew J. , Seshadri Ravi
Published: November 2004

Objective: To introduce and investigate the application, efficacy, and potential clinical complications of a continuous renal replacement therapy (CRRT) in a feline acute renal failure (ARF) patient.

Case summary: A domestic short‐haired cat presented for continued management of ARF of a presumed toxic etiology. Severe azotemia and uremic complications had been identified on initial presentation to a local urgent care facility, and the cat had been referred for renal replacement therapy following approximately 9 hours of conservative management. Continuous venovenous hemodiafiltration was performed over an approximately 25‐hour period, and a significant resolution of the cat's uremic derangements was obtained. Major complications included significant hypothermia and a single episode of hypocalcemia associated with utilization of citrate anticoagulation. All complications identified were readily managed. Following hospital discharge, long‐term medical support was not required, and no evidence of significant illness was noted 6 months following therapy.

New or unique information provided: CRRT represents a collection of extracorporeal blood purification techniques that utilize extended treatment periods for gradual, physiologically balanced correction of uremic toxicity. These therapies demonstrate significant promise in the treatment of ARF cats with actual or potential hemodynamic compromise, and prior advances in therapeutic administration have made these techniques readily accessible within the intensive care unit setting.
Spontaneous resolution of hypothermia‐induced atrial fibrillation in a dog
Authors: Campbell Scott A. , Day Thomas K.
Published: November 2004

Objective: To report a case of spontaneous resolution of atrial fibrillation secondary to hypothermia in a dog without detectable heart disease.

Case summary: An 8‐year‐old female spayed mixed breed dog presented with a history of prolonged exposure to below freezing environmental temperatures. The dog presented hypothermic (<32°C or <90°F) and minimally responsive to stimuli. The heart rate was 80 beats per minute (bpm) and irregular. Atrial fibrillation was diagnosed. The dog had pale mucous membranes, absent femoral pulses, and no obtainable blood pressure via indirect Doppler technique. Resuscitation fluids were administered and active external warming was instituted. Peripheral edema was observed during the rewarming phase and the irregular heart rate was noted to increase. The atrial fibrillation spontaneously resolved with no specific anti‐arrhythmic therapy. No underlying myocardial disease was found. The recovery of this dog was complete with a subsequent repeat of the echocardiogram and electrocardiogram (ECG) 8‐months later found to be within normal limits.
Development of a Two-Dimensional Computational Fluid Dynamics Approach for Computing Three-Dimensional Honeycomb Labyrinth Leakage
Authors: Choi Dong-Chun , Rhode David L.
Published: November 2004

A new approach for employing a two-dimensional computational fluid dynamics (CFD) model to approximately compute a three-dimensional flow field such as that in a honeycomb labyrinth seal was developed. The advantage of this approach is that it greatly reduces the computer resource requirement needed to obtain a solution of the leakage for the three-dimensional flow through a honeycomb labyrinth. After the leakage through the stepped labyrinth seal was measured, it was used in numerically determining the value of one dimension (DTF1) of the simplified geometry two-dimensional approximate CFD model. Then the capability of the two-dimensional model approach was demonstrated by using it to compute the three-dimensional flow that had been measured at different operating conditions, and in some cases different distance to contact values. It was found that very close agreement with measurements was obtained in all cases, except for that of intermediate clearance and distance to contact for two sets of upstream and downstream pressure. The two-dimensional approach developed here offers interesting benefits relative to conventional algebraic-equation models, particularly for evaluating labyrinth geometries/operating conditions that are different from that of the data employed in developing the algebraic model.
Determination of Chemical Kinetic Parameters of Surrogate Solid Wastes
Authors: Jinno D. , Gupta Ashwani K. , Yoshikawa K.
Published: November 2004

Results on the thermal decomposition behavior of several important components in solid wastes are presented under controlled chemical and thermal environments. Thermogravimetry (TGA) tests were conducted on the decomposition of cellulose, polyethylene, polypropylene, polystyrene and polyvinyl chloride in inert (nitrogen), and oxidative (air) atmospheres. Inert condition tests were performed at heating rates of 5, 10, 30, and 50°C/min while the oxidative condition tests were performed at one heating rate of 5°C/min. Differential scanning calorimetry (DSC) was also used to measure the heat flow into and out of the sample during thermal decomposition of the material. The TGA results on the mass evolution of the materials studied as a function of temperature showed that the cellulose contained a small amount of moisture whereas no moisture was found in the other materials examined. The DSC curve showed the heat flow into and out of the sample during the process of pyrolysis and oxidative pyrolysis. The temperature dependence and mass loss characteristics of materials were used to evaluate the Arrhenius kinetic parameters. The surrounding chemical environment, heating rate, and material composition and properties affect the overall decomposition rates under defined conditions. The composition of these materials was found to have a significant effect on the thermal decomposition behavior. Experimental results show that decomposition process shifts to higher temperatures at higher heating rates as a result of the competing effects of heat and mass transfer to the material. The results on the Arrhenius chemical kinetic parameters and heat of pyrolysis obtained from the thermal decomposition of the sample materials showed that different components in the waste have considerably different features. The thermal decomposition temperature, heat evolved and the kinetics parameters are significantly different various waste components examined. The amount of thermal energy required to destruct a waste material is only a small faction of the energy evolved from the material. These results assist in the design and development of advanced thermal destruction systems.