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Kinds of G. Terms modified by G. Selected AbstractsThe Attentional Resource Allocation Scale (ARAS): psychometric properties of a composite measure for dissociation and absorption,DEPRESSION AND ANXIETY, Issue 8 2010R. N. Carleton M.A. Abstract Background: Differences in attentional processes have been linked to the development and maintenance of psychopathology. Shifts in such processes have been described by the constructs Dissociation and Absorption. Dissociation occurs when external and/or internal stimuli are excluded from consciousness due to discrepant, rather than unitary, manifestations of cognitive awareness [Erdelyi MH. 1994: Int J Clin Exp Hypnosis 42:379,390]. In contrast, absorption can be conceptualized by a focus on limited stimuli, to the exclusion of other stimuli, because of unifying, rather than discrepant, manifestations of cognitive awareness. The Dissociative Experiences Scale [DES; Bernstein EM, Putnam FW. 1986: J Nerv Ment Dis 174:727,735] and Tellegen Absorption Scale [TAS; Tellegen A, Atkinson G. 1974: J Abnorm Psychol 83:268,277] are common measures of each construct; however, no factor analyses are available for the TAS and despite accepted overlap, no one has assessed the DES and TAS items simultaneously. Previous research suggests the constructs and factor structures need clarification, possibly including more parsimonious item inclusion [Lyons LC, Crawford HJ. 1997: Person Individ Diff 23:1071,1084]. The purpose of this study was to evaluate the factor structure of the DES and TAS and create a psychometrically stable measure of Dissociation and Absorption. Methods: This study included data from an undergraduate (n=841; 76% women) and a community sample (n=233; 86% women) who each completed the DES and TAS. Results: Exploratory factor analyses [Osborne JW (ed). 2008: Best Practices in Quantitative Methods. Los Angeles: Sage Publications Inc.] with all DES and TAS items suggested a 15-item 3-factor solution (i.e., imaginative involvement, dissociative amnesia, attentional dissociation). Confirmatory factor analyses resulted in excellent fit indices for the same solution. Conclusions: The items and factors were conceptualized in line with precedent research as the Attentional Resource Allocation Scale (ARAS). Comprehensive results, implications, and future research directions are discussed. Depression and Anxiety, 2010. © 2010 Wiley-Liss, Inc. [source] The 10-year course of psychosocial functioning among patients with borderline personality disorder and axis II comparison subjectsACTA PSYCHIATRICA SCANDINAVICA, Issue 2 2010M. C. Zanarini Zanarini MC, Frankenburg FR, Bradford Reich D, Fitzmaurice G. The 10-year course of psychosocial functioning among patients with borderline personality disorder and axis II comparison subjects. Objective:, The purpose of this study was to determine the 10-year course of the psychosocial functioning of patients with borderline personality disorder (BPD). Method:, The social and vocational functioning of 290 inpatients meeting both the Revised Diagnostic Interview for Borderlines (DIB-R) and DSM-III-R criteria for BPD and 72 axis II comparison subjects were carefully assessed during their index admission. Psychosocial functioning was reassessed using similar methods at five contiguous 2-year time periods. Results:, Borderline patients without good psychosocial functioning at baseline reported difficulty attaining it for the first time. Those who had such functioning at baseline reported difficulty retaining and then regaining it. In addition, over 90% of their poor psychosocial functioning was due to poor vocational but not social performance. Conclusion:, Good psychosocial functioning that involves both social and vocational competence is difficult for borderline patients to achieve and maintain over time. In addition, their vocational functioning is substantially more compromised than their social functioning. [source] The contribution of active medication to combined treatments of psychotherapy and pharmacotherapy for adult depression: a meta-analysisACTA PSYCHIATRICA SCANDINAVICA, Issue 6 2010P. Cuijpers Cuijpers P, van Straten A, Hollon SD, Andersson G. The contribution of active medication to combined treatments of psychotherapy and pharmacotherapy for adult depression: a meta-analysis. Objective:, Although there is sufficient evidence that combined treatments of psychotherapy and pharmacotherapy are more effective for depression in adults than each of the treatments alone, it remains unclear what the exact contribution of active medication is to the overall effects of combined treatments. This paper examines the contribution of active medication to combined psychotherapy and pharmacotherapy treatments. Method:, Meta-analysis of randomised controlled trials comparing the combination of psychotherapy and pharmacotherapy with the combination of psychotherapy and placebo. Results:, Sixteen identified studies involving 852 patients met our inclusion criteria. The standardised mean difference indicating the differences between the combination of psychotherapy and pharmacotherapy and the combination of psychotherapy and placebo was 0.25 (95% CI: 0.03,0.46), which corresponds to a numbers-needed-to-be-treated of 7.14. No significant differences between subgroups of studies were found. Conclusion:, Active medication has a small but significant contribution to the overall efficacy of combined treatments. [source] Light and electron microscopic study of the anterior oesophagus of Bulla striata (Mollusca, Opisthobranchia)ACTA ZOOLOGICA, Issue 2 2010Alexandre Lobo-da-Cunha Abstract Lobo-da-Cunha, A., Oliveira, E., Alves, Â., Coelho, R. and Calado, G. 2010. Light and electron microscopic study of the anterior oesophagus of Bulla striata (Mollusca, Opisthobranchia). ,Acta Zoologica (Stockholm) 91: 125,138. The anterior oesophagus of Bulla striata was investigated with light and electron microscopy. In the most anterior region, the ridges of the oesophageal wall are covered by a ciliated columnar epithelium forming large apical blebs which are released into the lumen, an activity that is particularly intense in the oesophageal pouch. In the last two-thirds of the anterior oesophagus, the epithelium is covered with microvilli embedded in a cuticle, but apocrine secretion and cilia are absent. Subepithelial secretory cells are very abundant in the oesophageal wall, except in the roof of the pouch. They have a long neck that crosses the epithelium, whereas the cell body containing the nucleus is embedded in the connective tissue. Large electron-lucent secretory vesicles and many Golgi stacks fill most of their cytoplasm. The histochemical and cytochemical assays show that these cells secrete acid mucopolysaccharides. With the current and future studies we aim to obtain data for the establishment of relationships between morphofunctional features of the digestive system and food types in cephalaspideans. Additionally, the new data about the oesophageal pouch of B. striata may be useful for the establishment of eventual homologies with the oesophageal diverticula of other opisthobranchs. [source] Biodiversity and distribution of epibiontic communities on Caridina ensifera (Crustacea, Decapoda, Atyidae) from Lake Poso: comparison with another ancient lake system of Sulawesi (Indonesia)ACTA ZOOLOGICA, Issue 2 2010Gregorio Fernandez-Leborans Abstract Fernandez-Leborans, G. and von Rintelen, K. 2010. Biodiversity and distribution of epibiontic communities on Caridina ensifera (Crustacea, Decapoda, Atyidae) from Lake Poso: comparison with another ancient lake system of Sulawesi (Indonesia). , Acta Zoologica (Stockholm) 91: 163,175 The epibiont communities of the shrimp Caridina ensifera, endemic to Lake Poso (Sulawesi, Indonesia), were analysed. Most of the epibiont species were ciliated protozoa belonging to three suctorian genera (Acineta, Podophrya and Spelaeophrya), three peritrich genera (Zoothamnium, Vorticella and Cothurnia), and a haptorid genus (Amphileptus). There was also a rotifer epibiont of the genus Embata. Epibionts were identified to species level. There were 14 to 1114 epibionts per shrimp. The distribution of the epibiont species on the surface of the basibiont was recorded, calculating the number on the different colonized individuals of C. ensifera. The most abundant species, Zoothamnium intermedium and Acineta sulawesiensis, were also the most widely distributed. There was a significant difference between the spatial distributions of the different epibiont species. The analysis of the number of the epibiont species throughout the anteroposterior axis of the shrimp showed a gradient from the anterior to the posterior end of the body. Data from Lake Poso were compared with those of the Malili lake system (Sulawesi), obtained from its endemic shrimp, Caridina lanceolata. Lake Poso had the highest mean diversity, while Lake Mahalona showed the highest maximum diversity. All lakes were correlated with respect to the mean number of epibionts on the anatomical units of the shrimp, which showed a similar general distribution. The distributions of the different epibiont species were compared between the lakes. The possible adaptations of the epibionts as well as the colonization patterns were discussed. From the statistical results and the analysis of the distributions, we propose that in these communities epibiont species have a pattern of colonization in which they follow a behaviour as a whole; each species has a differential distribution, with the species occupying the available substratum with the particular requirements of each functional group, but there is a trend towards maintaining an equilibrium among species and groups, compensating for diversity and number of individuals. In all lakes there was an epibiont distribution model comprising the maintenance of an anteroposterior axis gradient, which was supported by the fluctuation in diversity and number of individuals of the different functional groups of epibiont species. The functional role of the different groups of species seems to tend towards sustainability with little global variation among the lakes. [source] A new dimension in combining data?ACTA ZOOLOGICA, Issue 1 2010The use of morphology, phylogenomic data in metazoan systematics Abstract Giribet, G. 2010. A new dimension in combining data? The use of morphology and phylogenomic data in metazoan systematics. ,Acta Zoologica (Stockholm) 91: 11,19 Animal phylogenies have been traditionally inferred by using the character state information derived from the observation of a diverse array of morphological and anatomical features, but the incorporation of molecular data into the toolkit of phylogenetic characters has shifted drastically the way researchers infer phylogenies. A main reason for this is the ease at which molecular data can be obtained, compared to, e.g., traditional histological and microscopical techniques. Researchers now routinely use genomic data for reconstructing relationships among animal phyla (using whole genomes or Expressed Sequence Tags) but the amount of morphological data available to study the same phylogenetic patterns has not grown accordingly. Given the disparity between the amounts of molecular and morphological data, some authors have questioned entire morphological programs. In this review I discuss issues related to the combinability of genomic and morphological data, the informativeness of each set of characters, and conclude with a discussion of how morphology could be made scalable by utilizing new techniques that allow for non-intrusive examination of large amounts of preserved museum specimens. Morphology should therefore remains a strong field in evolutionary and comparative biology, as it continues to provide information for inferring phylogenetic patterns, is an important complement for the patterns derived from the molecular data, and it is the common nexus that allows studying fossil taxa with large data sets of molecular data. [source] Microchip-based small, dense low-density lipoproteins assay for coronary heart disease risk assessmentELECTROPHORESIS, Issue 9 2008Hua Wang Abstract Small, dense low-density lipoprotein (sdLDL) has been accepted as an emerging cardiovascular risk factor, and there has been an increasing interest in analytical methods for sdLDL profiling for diagnosis. Serum sdLDL may be measured by different laboratory techniques, but all these methods are laborious, time-consuming, and costly. Recently, we have demonstrated that a low-temperature bonding of quartz microfluidic chips for serum lipoproteins analysis (Zhuang, G., Jin, Q., Liu, J., Cong, H. et al., Biomed. Microdevices 2006, 8, 255,261). In contrast to this previous study, we chose SDS as anionic surfactant to modify both lipoproteins and the channel surface to minimize lipoprotein adsorption and improve the resolution of lipoprotein separation. Two major LDL subclass patterns including large, buoyant LDL (lLDL), sdLDL, and high-density lipoprotein (HDL) were effectively separated with high reproducibility. RSD values of the migration time (min) and peak areas of standard LDL and HDL were 6.28, 4.02, 5.02, and 2.5%, respectively. Serum lipoproteins of 15 healthy subjects and 15 patients with coronary heart disease (CHD) were separated by microchip CE. No peaks of sdLDL were detected in serum samples of healthy subjects while sdLDL fractional peaks were observed in patients' entire serum samples. These results suggested that the microchip-based sdLDLs assay was a simple, rapid, and highly efficient technique and significantly improved the analysis of CHD risk factors. [source] Capillary electrophoresis-mass spectrometry characterisation of secondary metabolites from the antihyperglycaemic plant Genista teneraELECTROPHORESIS, Issue 11 2006Emma L. Edwards Abstract Genista tenera is endemic to the Portuguese island of Madeira, where an infusion of the aerial parts of the plant is used in folk medicine as an antidiabetic agent. Consequently the medicinal properties of the secondary metabolites of this plant have been the subject of an ongoing study. A recently reported LC-MS method using a 100,min separation allowed identification of five flavonoid components in an extract of the aerial parts of this plant. In order to obtain additional information on the range and complexity of the plant's secondary metabolite components a CE-MS method has been developed and applied for the analysis of an extract of G.,tenera. Twenty-six different components are distinguished in an analysis time of only 10,min. Results demonstrate that CE-MS/MS rapidly generates data complementary to those obtainable by LC-MS/MS and is particularly suited to the analysis of plant metabolites where concentration is not limiting. [source] The effect of aerobic exercise on treatment-related acute toxicity in men receiving radical external beam radiotherapy for localised prostate cancerEUROPEAN JOURNAL OF CANCER CARE, Issue 5 2010G. KAPUR frcr KAPUR G., WINDSOR P.M. & Mc COWAN C. (2010) European Journal of Cancer Care19, 643,647 The effect of aerobic exercise on treatment-related acute toxicity in men receiving radical external beam radiotherapy for localised prostate cancer We retrospectively analysed acute radiation toxicity data for patients who had participated in a randomised controlled study in our centre in order to assess the impact of aerobic exercise on acute rectal and bladder morbidity during treatment. Data from 65 of 66 patients were analysed: 33 allocated into a control group (standard advice) and 33 into an exercise group (aerobic walking for 30 min at least three times per week) during 4 weeks of external beam radiotherapy; one patient in the exercise group withdrew after randomisation before starting radiotherapy. There was a trend towards less severe acute rectal toxicity in the exercise group with a statistically significant difference in mean toxicity scores over the 4 weeks of radiotherapy (P = 0.004), with no significant difference in bladder toxicity scores between the two groups (P = 0.123). The lack of an association for severity of bladder toxicity could be attributed to the confounding effect of lower urinary tract symptoms from their prostate cancer. Keeping active and being asked to adhere to a well-defined exercise schedule appears to reduce the severity of rectal toxicity during radiotherapy to the prostate. [source] Early (mucosal) gastric cancer with synchronous osteosclerotic bone metastases: a case reportEUROPEAN JOURNAL OF CANCER CARE, Issue 4 2010G. ANAGNOSTOPOULOS md ANAGNOSTOPOULOS G., SAKORAFAS G.H., KOSTOPOULOS P., MARGANTINIS G., TSIAKOS S. & PAVLAKIS G. (2010) European Journal of Cancer Care Early (mucosal) gastric cancer with synchronous osteosclerotic bone metastases: a case report Early gastric cancer (EGC) is defined as an adenocarcinoma confined to the gastric mucosa or submucosa, regardless of the presence of lymph node metastases. Early gastric cancer carries an excellent prognosis, with a 5-year survival rate at least 85% in most series. However, there are rare cases where distant metastases exist. Bone metastases are rare in gastric cancer; osteoblastic bone metastases are even rarer. We report a patient with EGC (mucosal) and synchronous osteosclerotic bone metastasis. To our knowledge, this is the first reported case of submucosal EGC with synchronous bone metastases. The patient was operated and he received adjuvant chemotherapy and radiotherapy. He died 18 months after gastric surgery from generalized disease. [source] Once-per-cycle pegfilgrastim in breast cancer patients treated with docetaxel/epidoxorubicin/cyclophosphamideEUROPEAN JOURNAL OF CANCER CARE, Issue 2 2010L. MONTELLA md MONTELLA L., ADDEO R., GUARRASI R., CENNAMO G., FAIOLA V., CAPASSO E., CARAGLIA M. & DEL PRETE S. (2010) European Journal of Cancer Care19, 200,204 Once-per-cycle pegfilgrastim in breast cancer patients treated with docetaxel/epidoxorubicin/cyclophosphamide The incidence of neutropenia following combination chemotherapy is significant in breast cancer and impairs patients' quality of life. Colony-stimulating factors significantly decrease the risk of febrile neutropenia (FN). Aim of the present study was to assess the efficacy and safety profile of once-per-cycle pegfilgrastim in reducing FN in breast cancer patients treated with docetaxel (75 mg/m2), epidoxorubicin (75 mg/m2), cyclophosphamide (500 mg/m2) administered every 3 weeks. Thirty-five breast cancer patients were enrolled. Chemotherapy was administered in adjuvant, neoadjuvant and metastatic setting respectively in 26, 4 and 5 patients. Toxicity was monitored with programmed clinical evaluation and blood sampling. All patients completed the therapeutic programme consisting of six cycles for overall 210 cycles. The FN appeared in 6 out of 35 patients (17%), requiring dose reduction in 3 patients. Hypertransaminasemia was registered in two patients. In one patient pegfilgrastim administration was stopped because of skin hypersensititivity reaction. In conclusion, pegfilgrastim was able to maintain doses and timing of docetaxel/epidoxorubicin/cyclophosphamide in almost all breast cancer patients treated in this series. The reduced need for daily administration of colony-stimulating factors, blood sampling, antibiotic therapy and hospitalization has a significant impact in terms of both quality of life and pharmaco-economic evaluations. [source] Justifying the expense of the cancer Clinical Nurse SpecialistEUROPEAN JOURNAL OF CANCER CARE, Issue 1 2010C.A. POLLARD ba POLLARD C.A., GARCEA G., PATTENDEN C.J., CURRAN R., NEAL C.P., BERRY D.P. & DENNISON A.R. (2009) European Journal of Cancer Care19, 72,79 Justifying the expense of the cancer Clinical Nurse Specialist In order to maximise patient care, assessment of the adequacy of the service provision by the Clinical Nurse Specialist (CNS) must be regularly undertaken. This study attempted to determine whether CNSs were providing an adequate service via retrospective and prospective audit. The results of a comprehensive audit of the work of the CNS within a tertiary referral Hepatobiliary Unit are presented. The audit involved postal and telephone questionnaires as well as prospective collection of data. The majority of responses from patients were positive, with many finding the CNS a useful and well-utilised contact. Overall, the CNSs performed well in each of their designated tasks; however, areas were still identified which could be further improved. Audit is essential in providing feedback to the CNS and to identify areas which require improvement. The CNS has evolved to meet a clinical gap in patient care, and as a result, the role of a CNS is frequently nebulous or poorly defined. This renders evaluation of the CNS problematic and fraught with difficulties. However, a thorough assessment can still be made using carefully constructed audit looking at each task of the CNS. [source] Elements of a neurobiological theory of hippocampal function: the role of synaptic plasticity, synaptic tagging and schemasEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2006R. G. M. MorrisArticle first published online: 8 JUN 200 Abstract The 2004 EJN Lecture was an attempt to lay out further aspects of a developing neurobiological theory of hippocampal function [Morris, R.G.M., Moser, E.I., Riedel, G., Martin, S.J., Sandin, J., Day, M. & O'Carroll, C. (2003) Phil. Trans. R. Soc. Lond. B Biol. Sci., 358, 773,786.] These are that (i) activity-dependent synaptic plasticity plays a key role in the automatic encoding and initial storage of attended experience; (ii) the persistence of hippocampal synaptic potentiation over time can be influenced by other independent neural events happening closely in time, an idea with behavioural implications for memory; and (iii) that systems-level consolidation of memory traces within neocortex is guided both by hippocampal traces that have been subject to cellular consolidation and by the presence of organized schema in neocortex into which relevant newly encoded information might be stored. Hippocampal memory is associative and, to study it more effectively than with previous paradigms, a new learning task is described which is unusual in requiring the incidental encoding of flavour,place paired associates, with the readout of successful storage being successful recall of a place given the flavour with which it was paired. NMDA receptor-dependent synaptic plasticity is shown to be critical for the encoding and intermediate storage of memory traces in this task, while AMPA receptor-mediated fast synaptic transmission is necessary for memory retrieval. Typically, these rapidly encoded traces decay quite rapidly over time. Synaptic potentiation also decays rapidly, but can be rendered more persistent by a process of cellular consolidation in which synaptic tagging and capture play a key part in determining whether or not it will be persistent. Synaptic tags set at the time of an event, even many trivial events, can capture the products of the synthesis of plasticity proteins set in train by events before, during or even after an event to be remembered. Tag,protein interactions stabilize synaptic potentiation and, by implication, memory. The behavioural implications of tagging are explored. Finally, using a different protocol for flavour,place paired associate learning, it is shown that rats can develop a spatial schema which represents the relative locations of several different flavours of food hidden at places within a familiar space. This schema is learned gradually but, once acquired, enables new paired associates to be encoded and stored in one trial. Their incorporation into the schema prevents rapid forgetting and suggests that schema play a key and hitherto unappreciated role in systems-level memory consolidation. The elements of what may eventually mature into a more formal neurobiological theory of hippocampal memory are laid out as specific propositions with detailed conceptual discussion and reference to recent data. [source] Repeated withdrawal from ethanol impairs acquisition but not expression of conditioned fearEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2003T. L. Ripley Abstract Repeated withdrawal from ethanol impairs acquisition of conditioned fear [Stephens, D.N., Brown, G., Duka, T. & Ripley, T.L. (2001) Eur. J. Neurosci., 14, 2023,2031]. This study further examined the effect of repeated withdrawal from ethanol on the expression and acquisition of fear conditioning. Following training, presentation of a cue associated with footshock (CS+) resulted in a suppression of operant responding for food reinforcement. In different groups, shock thresholds were manipulated to give weak or severe behavioural suppression. Rats were subsequently chronically treated with ethanol-containing liquid diet either continuously (single withdrawal) or with three withdrawal periods (repeated withdrawal). Ethanol treatment and withdrawal had no effect on conditioned suppression of responding tested 2 weeks after the final withdrawal, at either shock intensity. Nevertheless, extinction of conditioned fear was impaired in the repeated withdrawal group exposed to the higher shock intensity. In the high intensity group, the stimulus,shock association was then reversed, so that the previously neutral conditioned stimulus (CS,) became the CS+. Acquisition of suppression to the new CS+ was significantly less in the animals previously given repeated experience of withdrawal, confirming our previous finding. Thus, repeated withdrawal from ethanol lead to disruption in the acquisition of fear conditioning but had no effect on retrieval of an association formed prior to the ethanol-withdrawal experiences. [source] Kirk, G. The Biogeochemistry of Submerged Soils.EUROPEAN JOURNAL OF SOIL SCIENCE, Issue 2 20052004. xi + 291 pp. £9, Chichester, John Wiley & Sons, hardback. No abstract is available for this article. [source] ENVIRONMENTAL CONDITIONS AFFECT THE MAGNITUDE OF INBREEDING DEPRESSION IN SURVIVAL OF DARWIN'S FINCHESEVOLUTION, Issue 6 2002Lukas F. Keller Abstract Understanding the fitness consequences of inbreeding (inbreeding depression) is of importance to evolutionary and conservation biology. There is ample evidence for inbreeding depression in captivity, and data from wild populations are accumulating. However, we still lack a good quantitative understanding of inbreeding depression and what influences its magnitude in natural populations. Specifically, the relationship between the magnitude of inbreeding depression and environmental severity is unclear. We quantified inbreeding depression in survival and reproduction in populations of cactus finches (Geospiza scandens) and medium ground finches (Geospiza fortis) living on Isla Daphne Major in the Galapagos Archipelago. Our analyses showed that inbreeding strongly reduced the recruitment probability (probability of breeding given that an adult is alive) in both species. Additionally, in G. scandens, first-year survival of an offspring withf= 0.25 was reduced by 21% and adults withf= 0.25 experienced a 45% reduction in their annual probability of survival. The magnitude of inbreeding depression in both adult and juvenile survival of this species was strongly modified by two environmental conditions, food availability and number of competitors. In juveniles, inbreeding depression was only present in years with low food availability, and in adults inbreeding depression was five times more severe in years with low food availability and large population sizes. The combination of relatively severe inbreeding depression in survival and the reduced recruitment probability led to the fact that very few inbred G. scandens ever succeeded in breeding. Other than recruitment probability, no other trait showed evidence of inbreeding depression in G. fortis, probably for two reasons: a relatively high rate of extrapair paternity (20%), which may lead to an underestimate of the apparent inbreeding depression, and low sample sizes of highly inbred G. fortis, which leads to low statistical power. Using data from juvenile survival, we estimated the number of lethal equivalents carried by G. scandens, G. fortis, and another congener, G. magnirostris. These results suggest that substantial inbreeding depression can exist in insular populations of birds, and that the magnitude of the inbreeding depression is a function of environmental conditions. [source] The oxidation process of Antarctic fish hemoglobinsFEBS JOURNAL, Issue 9 2004Luigi Vitagliano Analysis of the molecular properties of proteins extracted from organisms living under extreme conditions often highlights peculiar features. We investigated by UV-visible spectroscopy and X-ray crystallography the oxidation process, promoted by air or ferricyanide, of five hemoglobins extracted from Antarctic fishes (Notothenioidei). Spectroscopic analysis revealed that these hemoglobins share a common oxidation pathway, which shows striking differences from the oxidation processes of hemoglobins from other vertebrates. Indeed, simple exposure of these hemoglobins to air leads to the formation of a significant amount of the low-spin hexacoordinated form, denoted hemichrome. This hemichrome form, which is detected under a variety of experimental conditions, can be reversibly transformed to either carbomonoxy or deoxygenated forms with reducing agents. Interestingly, the spectra of the fully oxidized species, obtained by treating the protein with ferricyanide, show the simultaneous presence of peaks corresponding to different hexacoordinated states, the aquomet and the hemichrome. In order to assign the heme region state of the , and , chains, the air-oxidized and ferricyanide-oxidized forms of Trematomus bernacchii hemoglobin were crystallized. Crystallographic analysis revealed that these forms correspond to an ,(aquomet)-,(bishistidyl-hemichrome) state. This demonstrates that the , and , chains of Antarctic fish hemoglobins follow very different oxidation pathways. As found for Trematomus newnesi hemoglobin in a partial hemichrome state [Riccio, A., Vitagliano, L., di Prisco, G., Zagari, A. & Mazzarella, L. (2002) Proc. Natl Acad. Sci. USA99, 9801,9806], the quaternary structures of these ,(aquomet)-,(bishistidyl-hemichrome) forms are intermediate between the physiological R and T hemoglobin states. Together, these structures provide information on the general features of this intermediate state. [source] The resident endoplasmic reticulum protein, BAP31, associates with ,-actin and myosin B heavy chainFEBS JOURNAL, Issue 2 2003Analysis by capillary liquid chromatography microelectrospray tandem MS BAP31 is a 28-kDa integral membrane protein of the endoplasmic reticulum whose cytosolic domain contains two caspase recognition sites that are preferentially cleaved by initiator caspases, such as caspase-8. Recently, we reported that the caspase-resistant BAP31 inhibited Fas-mediated apoptotic membrane fragmentation and the release of cytochrome c from mitochondria in KB epithelial cells (Nguyen M., Breckenridge G., Ducret A & Shore G. (2000) Mol. Cell. Biol.20, 6731,6740). We describe here the characterization by capillary liquid chromatography microelectrospray tandem MS of a BAP31 immunocomplex isolated from a HepG2 cell lysate in the absence of a death signal. We show that BAP31 specifically associates with nonmuscle myosin heavy chain B and nonmuscle ,-actin, two components of the cytoskeleton actomyosin complex. Collectively, these data confirm that BAP31, in addition to its potential role as a chaperone, may play a fundamental role in the structural organization of the cytoplasm. Here we also show that Fas stimulation of apoptosis releases BAP31 associations with these motor proteins, a step that may contribute to extranuclear events, such as membrane remodelling, during the execution phase of apoptosis. [source] Interleukin-6-induced proliferation of pre-B cells mediated by receptor complexes lacking the SHP2/SOCS3 recruitment sites revisitedFEBS JOURNAL, Issue 24 2001Kerstin Friederichs Interleukin-6 (IL-6) induces B-cell proliferation by binding to receptor complexes composed of a specific ,-receptor (gp80; CD126) and the signal transducing receptor subunit gp130 (CD130). Immediately after receptor complex activation, signal transducers and activators of transcription (STATs) 1 and 3 and the Src-homology domain-containing protein tyrosine phosphatase 2 (SHP2) are recruited to gp130 and subsequently tyrosine phosphorylated. The activated dimerized STATs translocate to the nucleus and bind to enhancer elements of IL-6-inducible genes. SHP2 acts as an adapter and links the Jak/STAT pathway to the Ras/Raf/MAPK cascade but it is also involved in signal attenuation. Whereas STAT3 activation appears to be crucial for all biological activities of IL-6, the requirement of SHP2-activation depends on the individual biological response analyzed. The requirement of SHP2 activation for the pre-B cell (Ba/F3) proliferation has been reported previously [Fukada, T., Hibi, M., Yamanaka, Y., Takahashi-Tezuka, M., Fujitani, Y., Yamaguchi, T., Nakajima, K. & Hirano, T. (1996) Immunity5, 449,460]. In contrast, we have recently demonstrated that the presence of a single STAT-recruitment site within gp130 is sufficient for IL-6- induced proliferation of Ba/F3 cells [Schmitz, J., Dahmen, H., Grimm, C., Gendo, C., Müller-Newen, G., Heinrich, P.C. & Schaper, F. (2000) J. Immunol.164, 848,854]. To unravel this discrepancy we analyzed the IL-6-induced dose-dependent proliferation of Ba/F3 cells mediated by receptor complexes lacking SHP2/SOCS3 recruitment sites. Surprisingly, pre-B cells, after stimulation with low amounts of IL-6, proliferate much more efficiently in the absence of the activated SHP2 than in the presence of the tyrosine phosphatase. Therefore, SHP2 activation appears to be relevant for IL-6-induced proliferation only after stimulation with very large amounts of IL-6. [source] Potency and selectivity of inhibition of cathepsin K, L and S by their respective propeptidesFEBS JOURNAL, Issue 20 2000Jocelyne Guay The prodomains of several cysteine proteases of the papain family have been shown to be potent inhibitors of their parent enzymes. An increased interest in cysteine proteases inhibitors has been generated with potential therapeutic targets such as cathepsin K for osteoporosis and cathepsin S for immune modulation. The propeptides of cathepsin S, L and K were expressed as glutathione S -transferase-fusion proteins in Escherichia coli. The proteins were purified on glutathione affinity columns and the glutathione S -transferase was removed by thrombin cleavage. All three propeptides were tested for inhibitor potency and found to be selective within the cathepsin L subfamily (cathepsins K, L and S) compared with cathepsin B or papain. Inhibition of cathepsin K by either procathepsin K, L or S was time-dependent and occurred by an apparent one-step mechanism. The cathepsin K propeptide had a Ki of 3.6,6.3 nm for each of the three cathepsins K, L and S. The cathepsin L propeptide was at least a 240-fold selective inhibitor of cathepsin K (Ki = 0.27 nm) and cathepsin L (Ki = 0.12 nm) compared with cathepsin S (Ki = 65 nm). Interestingly, the cathepsin S propeptide was more selective for inhibition of cathepsin L (Ki = 0.46 nm) than cathepsin S (Ki = 7.6 nm) itself or cathepsin K (Ki = 7.0 nm). This is in sharp contrast to previously published data demonstrating that the cathepsin S propeptide is equipotent for inhibition of human cathepsin S and rat and paramecium cathepsin L [Maubach, G., Schilling, K., Rommerskirch, W., Wenz, I., Schultz, J.E., Weber, E. & Wiederanders, B. (1997), Eur J. Biochem. 250, 745,750]. These results demonstrate that limited selectivity of inhibition can be measured for the procathepsins K, L and S vs. the parent enzymes, but selective inhibition vs. cathepsin B and papain was obtained. [source] Differential mechanism-based labeling and unequivocal activity assignment of the two active sites of intestinal lactase/phlorizin hydrolaseFEBS JOURNAL, Issue 24 2000Juan C. Díaz Arribas Milk lactose is hydrolysed to galactose and glucose in the small intestine of mammals by the lactase/phlorizin hydrolase complex (LPH; EC 3.2.1.108/62). The two enzymatic activities, lactase and phlorizin hydrolase, are located in the same polypeptide chain. According to sequence homology, mature LPH contains two different regions (III and IV), each of them homologous to family 1 glycosidases and each with a putative active site. There has been some discrepancy with regard to the assignment of enzymatic activity to the two active sites. Here we show differential reactivity of the two active sites with mechanism-based glycosidase inhibitors. When LPH is treated with 2,,4,-dinitrophenyl 2-deoxy-2-fluoro-,- d -glucopyranoside (1) and 2,,4,-dinitrophenyl-2-deoxy-2-fluoro-,- d -galactopyranoside (2), known mechanism-based inhibitors of glycosidases, it is observed that compound 1 preferentially inactivates the phlorizin hydrolase activity whereas compound 2 is selective for the lactase active site. On the other hand, glycals (d -glucal and d -galactal) competitively inhibit lactase activity but not phlorizin hydrolase activity. This allows labeling of the phlorizin site with compound 1 by protection with a glycal. By differential labeling of each active site using 1 and 2 followed by proteolysis and MS analysis of the labeled fragments, we confirm that the phlorizin hydrolysis occurs mainly at the active site located at region III of LPH and that the active site located at region IV is responsible for the lactase activity. This assignment is coincident with that proposed from the results of recent active-site mutagenesis studies [Zecca, L., Mesonero, J.E., Stutz, A., Poiree, J.C., Giudicelli, J., Cursio, R., Gloor, S.M. & Semenza, G. (1998) FEBS Lett.435, 225,228] and opposite to that based on data from early affinity labeling with conduritol B epoxide [Wacker, W., Keller, P., Falchetto, R., Legler, G. & Semenza, G. (1992) J. Biol. Chem.267, 18744,18752]. [source] Components of the essential oil from Glehnia littoralisFLAVOUR AND FRAGRANCE JOURNAL, Issue 3 2001Mitsuo Miyazawa Abstract The chemical composition of the essential oils from Glehnia littoralis of aerial and root parts growing cultivated in Niigata Collage of Pharmacy were examined by GC, GC,MS and 1H-NMR. Sixty seven components were characterized of G. littoralis aerial parts, with ,-phellandrene (12.96%), propyl octanoate (16.89%), hexadecanoic acid (14.45%), linoleic acid (8.79%) and methyl linolenate (5.47%) as the major constituents. Sixty six components were identified in the oil of root parts, with ,-pinene (13.40%), ,-phellandrene (22.93%) and germacrene B (6.68%) as the major constituents. Copyright © 2001 John Wiley & Sons, Ltd. [source] Teaching and Learning Guide for: The Geopolitics of Climate ChangeGEOGRAPHY COMPASS (ELECTRONIC), Issue 5 2008Jon Barnett Author's Introduction Climate change is a security problem in as much as the kinds of environmental changes that may result pose risks to peace and development. However, responsibilities for the causes of climate change, vulnerability to its effects, and capacity to solve the problem, are not equally distributed between countries, classes and cultures. There is no uniformity in the geopolitics of climate change, and this impedes solutions. Author Recommends 1.,Adger, W. N., et al. (eds) (2006). Fairness in adaptation to climate change. Cambridge, MA: MIT Press. A comprehensive collection of articles on the justice dimensions of adaptation to climate change. Chapters discuss potential points at which climate change becomes ,dangerous', the issue of adaptation under the United Nations Framework Convention on Climate Change (UNFCCC), the unequal outcomes of adaptation within a society, the effects of violent conflict on adaptation, the costs of adaptation, and examples from Bangladesh, Tanzania, Botswana, and Hungary. 2.,Leichenko, R., and O'Brien, K. (2008). Environmental change and globalization: double exposures. New York: Oxford University Press. This book uses examples from around the world to show the way global economic and political processes interact with environmental changes to create unequal outcomes within and across societies. A very clear demonstration of the way vulnerability to environmental change is as much driven by social processes as environmental ones, and how solutions lie within the realm of decisions about ,development' and ,environment'. 3.,Nordås, R., and Gleditsch, N. (2007). Climate conflict: common sense or nonsense? Political Geography 26 (6), pp. 627,638. doi:10.1016/j.polgeo.2007.06.003 An up-to-date, systematic and balanced review of research on the links between climate change and violent conflict. See also the other papers in this special issue of Political Geography. 4.,Parry, M., et al. (eds) (2007). Climate change 2007: impacts adaptation and vulnerability. Contribution of Working Group II to the fourth assessment report of the intergovernmental panel on climate change. Cambridge, UK: Cambridge University Press. The definitive review of all the peer-reviewed research on the way climate change may impact on places and sectors across the world. Includes chapters on ecosystems, health, human settlements, primary industries, water resources, and the major regions of the world. All chapters are available online at http://www.ipcc.ch/ipccreports/ar4-wg2.htm 5.,Salehyan, I. (2008). From climate change to conflict? No consensus yet. Journal of Peace Research 45 (3), pp. 315,326. doi:10.1177/0022343308088812 A balanced review of research on the links between climate change and conflict, with attention to existing evidence. 6.,Schwartz, P., and Randall, D. (2003). An abrupt climate change scenario and its implications for United States national security. San Francisco, CA: Global Business Network. Gives insight into how the US security policy community is framing the problem of climate change. This needs to be read critically. Available at http://www.gbn.com/ArticleDisplayServlet.srv?aid=26231 7.,German Advisory Council on Global Change. (2007). World in transition: climate change as a security risk. Berlin, Germany: WBGU. A major report from the German Advisory Council on Global Change on the risks climate changes poses to peace and stability. Needs to be read with caution. Summary and background studies are available online at http://www.wbgu.de/wbgu_jg2007_engl.html 8.,Yamin, F., and Depedge, J. (2004). The International climate change regime: a guide to rules, institutions and procedures. Cambridge, UK: Cambridge University Press. A clear and very detailed explanation of the UNFCCC's objectives, actors, history, and challenges. A must read for anyone seeking to understand the UNFCCC process, written by two scholars with practical experience in negotiations. Online Materials 1.,Environmental Change and Security Program at the Woodrow Wilson International Center for Scholars http://www.wilsoncenter.org/ecsp The major website for information about environmental security. From here, you can download many reports and studies, including the Environmental Change and Security Project Report. 2.,Global Environmental Change and Human Security Project http://www.gechs.org This website is a clearing house for work and events on environmental change and human security. 3.,Intergovernmental Panel on Climate Change (IPCC) http://www.ipcc.ch/ From this website, you can download all the chapters of all the IPCC's reports, including its comprehensive and highly influential assessment reports, the most recent of which was published in 2007. The IPCC were awarded of the Nobel Peace Prize ,for their efforts to build up and disseminate greater knowledge about man-made (sic) climate change, and to lay the foundations for the measures that are needed to counteract such change'. 4.,Tyndall Centre for Climate Change Research http://www.tyndall.ac.uk The website of a major centre for research on climate change, and probably the world's leading centre for social science based analysis of climate change. From this site, you can download many publications about mitigation of and adaptation to climate change, and about various issues in the UNFCCC. 5.,United Nations Framework Convention on Climate Change http://unfccc.int/ The website contains every major document relation to the UNFCCC and its Kyoto Protocol, including the text of the agreements, national communications, country submissions, negotiated outcomes, and background documents about most key issues. Sample Syllabus: The Geopolitics of Climate Change topics for lecture and discussion Week I: Introduction Barnett, J. (2007). The geopolitics of climate change. Geography Compass 1 (6), pp. 1361,1375. United Nations Secretary General, Kofi Annan, address to the 12th Conference of Parties to the United Nations Framework Convention on Climate Change, Nairobi, 15 November 2006. Available online at http://www.unep.org/Documents.Multilingual/Default.asp?DocumentID=495&ArticleID=5424&l=en Week II: The History and Geography of Greenhouse Gas Emissions Topic: The drivers of climate change in space and time Reading Baer, P. (2006). Adaptation: who pays whom? In: Adger, N., et al. (eds) Fairness in adaptation to climate change. Cambridge, MA: MIT Press, pp. 131,154. Boyden, S., and Dovers, S. (1992). Natural-resource consumption and its environmental impacts in the Western World: impacts of increasing per capita consumption. Ambio 21 (1), pp. 63,69. Week III: The Environmental Consequences of climate change Topic: The risks climate change poses to environmental systems Reading Intergovernmental Panel on Climate Change. (2007). Climate change 2007: climate change impacts, adaptation and vulnerability: summary for policymakers. Geneva, Switzerland: IPCC Secretariat. Watch: Al Gore. The Inconvenient Truth. Weeks IV and V: The Social Consequences of Climate Change Topic: The risks climate change poses to social systems Reading Adger, W. N. (1999). Social vulnerability to climate change and extremes in coastal Vietnam. World Development 27, pp. 249,269. Comrie, A. (2007). Climate change and human health. Geography Compass 1 (3), pp. 325,339. Leary, N., et al. (2006). For whom the bell tolls: vulnerability in a changing climate. A Synthesis from the AIACC project, AIACC Working Paper No. 21, International START Secretariat, Florida. Stern, N. (2007). Economics of climate change: the Stern review. Cambridge, UK: Cambridge University Press (Chapters 3,5). Week VI: Mitigation of Climate Change: The UNFCCC Topic: The UNFCCC and the Kyoto Protocol Reading Najam, A., Huq, S., and Sokona, Y. (2003). Climate negotiations beyond Kyoto: developing countries concerns and interests. Climate Policy 3 (3), pp. 221,231. UNFCCC Secretariat. (2005). Caring for climate: a guide to the climate change convention and the Kyoto Protocol. Bonn, Germany: UN Framework Convention on Climate Change Secretariat. Weeks VII and VIII: Adaptation to Climate Change Topic: What can be done to allow societies to adapt to avoid climate impacts? Reading Adger, N., et al. (2007). Assessment of adaptation practices, options, constraints and capacity. In: Parry, M., et al. (eds) Climate change 2007: impacts, adaptation and vulnerability. Contribution of Working Group II to the fourth assessment report of the intergovernmental panel on climate change. Cambridge, UK: Cambridge University Press, pp. 717,744. Burton, I., et al. (2002). From impacts assessment to adaptation priorities: the shaping of adaptation policy. Climate Policy 2 (2,3), pp. 145,159. Eakin, H., and Lemos, M. C. (2006). Adaptation and the state: Latin America and the challenge of capacity-building under globalization. Global Environmental Change: Human and Policy Dimensions 16 (1), pp. 7,18. Ziervogel, G., Bharwani, S., and Downing, T. (2006). Adapting to climate variability: pumpkins, people and policy. Natural Resources Forum 30, pp. 294,305. Weeks IX and X: Climate Change and Migration Topic: Will climate change force migration? Readings Gaim, K. (1997). Environmental causes and impact of refugee movements: a critique of the current debate. Disasters 21 (1), pp. 20,38. McLeman, R., and Smit, B. (2006). Migration as adaptation to climate change. Climatic Change 76 (1), pp. 31,53. Myers, N. (2002). Environmental refugees: a growing phenomenon of the 21st century. Philosophical Transactions of the Royal Society 357 (1420), pp. 609,613. Perch-Nielsen, S., Bättig, M., and Imboden, D. (2008). Exploring the link between climate change and migration. Climatic Change (online first, forthcoming); doi:10.1007/s10584-008-9416-y Weeks XI and XII: Climate Change and Violent Conflict Topic: Will Climate change cause violent conflict? Readings Barnett, J., and Adger, N. (2007). Climate change, human security and violent conflict. Political Geography 26 (6), pp. 639,655. Centre for Strategic and International Studies. (2007). The age of consequences: the foreign policy and national security implications of global climate change. Washington, DC: CSIS. Nordås, R., and Gleditsch, N. (2007). Climate conflict: common sense or nonsense? Political Geography 26 (6), pp. 627,638. Schwartz, P., and Randall, D. (2003). An abrupt climate change scenario and its implications for United States national security. San Francisco, CA: Global Business Network. [online]. Retrieved on 8 April 2007 from http://www.gbn.com/ArticleDisplayServlet.srv?aid=26231 Focus Questions 1Who is most responsible for climate change? 2Who is most vulnerable to climate change? 3Does everyone have equal power in the UNFCCC process? 4Will climate change force people to migrate? Who? 5What is the relationship between adaptation to climate change and violent conflict? [source] Hydrometeorological behaviour of pine and larch forests in eastern SiberiaHYDROLOGICAL PROCESSES, Issue 1 2004Shuko Hamada Abstract Seasonal changes in the water and energy exchanges over a pine forest in eastern Siberia were investigated and compared with published data from a nearby larch forest. Continuous observations (April to August 2000) were made of the eddy-correlation sensible heat flux and latent heat flux above the canopy. The energy balance was almost closed, although the sum of the turbulent fluxes sometimes exceeded the available energy flux (Rn , G) when the latent heat flux was large; this was related to the wind direction. We examined the seasonal variation in energy balance components at this site. The seasonal variation and magnitude of the sensible heat flux (H) was similar to that of the latent heat flux (,E), with maximum values occurring in mid-June. Consequently, the Bowen ratio was around 1·0 on many days during the study period. On some clear days just after rainfall, ,E was very large and the sum of H and ,E exceeded Rn , G. The evapotranspiration rate above the dry canopy from May to August was 2·2 mm day,1. The contributions of understory evapotranspiration (Eu) and overstory transpiration (Eo) to the evapotranspiration of the entire ecosystem (Et) were both from 25 to 50% throughout the period analysed. These results suggest that Eu plays a very important role in the water cycle at this site. From snowmelt through the tree growth season (23 April to 19 August 2000), the total incoming water, comprised of the sum of precipitation and the water equivalent of the snow at the beginning of the melt season, was 228 mm. Total evapotranspiration from the forest, including interception loss and evaporation from the soil when the canopy was wet, was 208,254 mm. The difference between the incoming and outgoing amounts in the water balance was from +20 to ,26 mm. The water and energy exchanges of the pine and larch forest differed in that ,E and H increased slowly in the pine forest, whereas ,E increased rapidly in the larch forest and H decreased sharply after the melting season. Consequently, the shape of the Bowen ratio curves at the two sites differed over the period analysed, as a result of the differences in the species in each forest and in soil thawing. Copyright © 2003 John Wiley & Sons, Ltd. [source] Smoking during pregnancy: analysis of influencing factors using the Theory of Planned BehaviourINTERNATIONAL NURSING REVIEW, Issue 3 2010M. Ben Natan phd BEN NATAN M., VIKTORIA G. & SHAMRAI V. (2010) Smoking during pregnancy: analysis of influencing factors using the Theory of Planned Behaviour. International Nursing Review57, 388,394 Aim:, To investigate factors affecting women's intention to smoke during pregnancy. Design:, A descriptive, correlational, cross-sectional study, employing the Theory of Planned Behaviour (TPB). Methods:, A questionnaire that was constructed based on a literature review of research on smoking during pregnancy and on the TPB was administered to 201 Israeli female smokers aged 19,46. Descriptive, correlational and linear regression statistics were calculated. Results:, Behavioural attitudes (women's total appraisal of smoking during pregnancy), subjective norms (women's perception of the opinion of significant others regarding the specific behaviour) and perceived behavioural control (women's total appraisal of their control of the behaviour and perceived ease or difficulty of quitting smoking during pregnancy) were found to predict women's intention to smoke during pregnancy. Conclusions:, Nursing interventions guided by the TPB constructs may help Israeli women quit smoking during pregnancy and reduce the prevalence of smoking during pregnancy. [source] Red in tooth and claw: how top predators shape terrestrial ecosystemsJOURNAL OF ANIMAL ECOLOGY, Issue 4 2010Christopher N. Johnson Elmhagen, B., Ludwig, G., Rushton, S.P., Helle, P. & Linden, H. (2010) Top predators, mesopredators and their prey: interference ecosystems along bioclimatic productivity gradients. Journal of Animal Ecology79, 785,794. Top predators are increasingly recognized as important regulators of ecosystem structure. Elmhagen et al. in this issue show how a recolonizing population of lynx in Finland is in the process of imposing control of the abundance of a mesopredator, the red fox and relaxing predation pressure on a prey species. Their study shows how ecological restoration programs could use the power of top predators to limit mesopredator populations and control total predation pressure on prey species. [source] Sex ratio bias in the F1 adult progeny of African rice gall midge, Orseolia oryzivora H. and G. (Dipt., Cecidomyiidae)JOURNAL OF APPLIED ENTOMOLOGY, Issue 6-7 2006A. A. Omoloye Abstract:, Against the background of conflicting reports of variable sex ratio distribution in different populations of the African rice gall midge (AfRGM), Orseolia oryzivora Harris and Gagne, the number and sex ratios of F1 adult progeny produced per female from wild and screen house populations were investigated in the screen house at 27 ± 3°C, 60,70% relative humidity and 12 : 12 h (light : dark) photoperiod. Results indicated the occurrence of a single sex-biased ratio in all the F1 adult progeny produced per female of this pest. Regardless of the source, whether from wild or screen house population, each mated female AfRGM produced a full complement of either sex only but never both. The difference between the number of eggs laid and F1 adult progeny that emerged per female from wild and screen house populations was not significant (P > 0.05), indicating consistency in the occurrence of this phenomenon among AfRGM populations. The reason for this could not be ascertained in this study but AfRGM eggs must be fertilized for development and eclosion to occur. No F2 adults emerged when a cohort of emergents from the same female were allowed to re-infest susceptible seedlings, indicating absence of parthenogenesis. [source] GORDH, G.; HEADRICK, D. H.: A Dictionary of Entomology.JOURNAL OF APPLIED ENTOMOLOGY, Issue 5 20012001. ix+1032 pp. £75.00 (US$100.00)., UK: CABI Publishing, Wallingford [source] Microhabitat selection of Gyrodactylus salaris Malmberg on different salmonidsJOURNAL OF FISH DISEASES, Issue 12 2007R D Heinecke Abstract The microhabitat selection of the ectoparasite Gyrodactylus salaris (Lærdalselva strain, Norway) was investigated concurrently with studies on the parasite population growth on five strains of Atlantic salmon, Salmo salar L., and a strain of Danish rainbow trout, Oncorhynchus mykiss (Walbaum). The salmon used were hatchery-reared parr of East Atlantic strains [River Conon (Scotland), River Storå (western Denmark) and River Ätran (western Sweden)] and Baltic strains [Lule and Ume (eastern Sweden)]. The location and numbers of parasites were recorded on anaesthetized fish once a week from week 0 to week 8. The mean abundance of G. salaris steadily increased to high levels on the River Conon, Storå and Ätran strains until the end of the experiment. The mean abundance of G. salaris on the two Baltic strains (River Lule älv and River Ume älv) initially increased but after 4,7 weeks the growth of the parasite infrapopulations decreased markedly. The Danish rainbow trout strain showed the lowest abundances of all the fish species and strains. Gyrodactylus salaris preferentially selected the fins and head region when colonising the hosts (all species and strains). Increasing percentages of G. salaris on the tail fins of the East Atlantic strains and rainbow trout were found during the course of infection, whereas the two Baltic salmon strains experienced a decreasing percentage of parasites in this microhabitat. [source] Multi-coloring the Mycielskian of graphsJOURNAL OF GRAPH THEORY, Issue 4 2010Wensong Lin Abstract A k -fold coloring of a graph is a function that assigns to each vertex a set of k colors, so that the color sets assigned to adjacent vertices are disjoint. The kth chromatic number of a graph G, denoted by ,k(G), is the minimum total number of colors used in a k -fold coloring of G. Let µ(G) denote the Mycielskian of G. For any positive integer k, it holds that ,k(G) + 1,,k(µ(G)),,k(G) + k (W. Lin, Disc. Math., 308 (2008), 3565,3573). Although both bounds are attainable, it was proved in (Z. Pan, X. Zhu, Multiple coloring of cone graphs, manuscript, 2006) that if k,2 and ,k(G),3k,2, then the upper bound can be reduced by 1, i.e., ,k(µ(G)),,k(G) + k,1. We conjecture that for any n,3k,1, there is a graph G with ,k(G)=n and ,k(µ(G))=n+ k. This is equivalent to conjecturing that the equality ,k(µ(K(n, k)))=n+k holds for Kneser graphs K(n, k) with n,3k,1. We confirm this conjecture for k=2, 3, or when n is a multiple of k or n,3k2/ln k. Moreover, we determine the values of ,k(µ(C2q+1)) for 1,k,q. © 2009 Wiley Periodicals, Inc. J Graph Theory 63: 311,323, 2010 [source] |