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Significant Shift (significant + shift)
Selected AbstractsThe consequences of differential family survival rates and equalizing maternal contributions on the effective population size (Ne) of cultured silver-lipped pearl oysters, Pinctada maximaAQUACULTURE RESEARCH, Issue 8 2010Curtis E Lind Abstract The effective population size (Ne) is a critical gauge of how efficiently an aquaculture operation is capturing or maintaining genetic diversity and can govern the long-term success of genetic selection programmes. In communally reared pearl oysters (Pinctada maxima), high variance in family sizes is a significant contributor towards low Ne and its severity may be compounded by differential survival rates of individual families. To determine the effect of variable survival on Ne in cultured P. maxima, families from two commercial populations were analysed using DNA parentage analyses to monitor survival and changes in relative contributions. Significant shifts in relative contributions were observed between 72 days and 18 months of age in both commercial cohorts (P<0.001). Survival rates were found to be highly variable among families (ranging from 2.5% to 49.5%) when reared in a common environment. Additionally, we investigated whether equalizing maternal family sizes before communal rearing will reduce family size variance, and increase Ne, compared with stocking at naturally produced proportions. Family equalization (E) significantly improved Ne (P=0.013) compared with rearing at natural (N) proportions (E: Ne=7.18±0.34; N: Ne=5.60±0.15); however, this practice may unintentionally magnify negative influences of poor performing families if survival is correlated with other commercially important traits. It is concluded that highly variable family survival will affect Ne in communally reared P. maxima, and the practice of equalizing family sizes in order to maximize Ne may only become consistently beneficial once further progress is made towards understanding, and then reducing variation in family survival rates. [source] Effects of predator-induced visual and olfactory cues on 0+ perch (Perca fluviatilis L.) foraging behaviourECOLOGY OF FRESHWATER FISH, Issue 2 2006V. N. Mikheev Abstract,,, Foraging juvenile fish with relatively high food demands are usually vulnerable to various aquatic and avian predators. To compromise between foraging and antipredator activity, they need exact and reliable information about current predation risk. Among direct predator-induced cues, visual and olfactory signals are considered to be most important. Food intake rates and prey-size selectivity of laboratory-reared, naive young-of-the-year (YOY) perch, Perca fluviatilis, were studied in experiments with Daphnia magna of two size classes: 2.8 and 1.3 mm as prey and northern pike, Esox lucius, as predator. Neither total intake rate nor prey-size selectivity was modified by predator kairomones alone (water from an aquarium with a pike was pumped into the test aquaria) under daylight conditions. Visual presentation of pike reduced total food intake by perch. This effect was significantly more pronounced (synergistic) when visual and olfactory cues were presented simultaneously to foraging perch. Moreover, the combination of cues caused a significant shift in prey-size selection, expressed as a reduced proportion of large prey in the diet. Our observations demonstrate that predator-induced olfactory cues alone are less important modifiers of the feeding behaviour of naive YOY perch than visual cues under daylight conditions. However, pike odour acts as a modulatory stimulus enhancing the effects of visual cues, which trigger an innate response in perch. [source] Ascomycete communities in the rhizosphere of field-grown wheat are not affected by introductions of genetically modified Pseudomonas putida WCS358rENVIRONMENTAL MICROBIOLOGY, Issue 11 2005Mareike Viebahn Summary A long-term field experiment (1999,2002) was conducted to monitor effects on the indigenous microflora of Pseudomonas putida WCS358r and two transgenic derivatives constitutively producing phenazine-1-carboxylic acid (PCA) or 2,4-diacetylphloroglucinol (DAPG). The strains were introduced as seed coating on wheat into the same field plots each year. Rhizosphere populations of ascomycetes were analysed using denaturing gradient gel electrophoresis (DGGE). To evaluate the significance of changes caused by the genetically modified microorganisms (GMMs), they were compared with effects caused by a crop rotation from wheat to potato. In the first year, only the combination of both GMMs caused a significant shift in the ascomycete community. After the repeated introductions this effect was no longer evident. However, cropping potato significantly affected the ascomycete community. This effect persisted into the next year when wheat was grown. Clone libraries were constructed from samples taken in 1999 and 2000, and sequence analysis indicated ascomycetes of common genera to be present. Most species occurred in low frequencies, distributed almost evenly in all treatments. However, in 1999 Microdochium occurred in relatively high frequencies, whereas in the following year no Microdochium species were detected. On the other hand, Fusarium -like organisms were low in 1999, and increased in 2000. Both the DGGE and the sequence analysis revealed that repeated introduction of P. putida WCS358r had no major effects on the ascomycete community in the wheat rhizosphere, but demonstrated a persistent difference between the rhizospheres of potato and wheat. [source] Response of zooplankton communities to liquid creosote in freshwater microcosmsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 2 2001Paul K. Sibley Abstract In this study, the response of zooplankton communities to single applications of liquid creosote in model aquatic ecosystems (microcosms) was evaluated. Liquid creosote was applied to 14 microcosms at concentrations ranging from 0.06 to 109 mg/L. Two microcosms served as controls. Zooplankton samples were collected from each microcosm on days 7 and 1 before treatment and on days 2, 5, 7, 14, 21, 28, 43, 55, and 83 following treatment. Temporal changes (response-recovery) in composition of the zooplankton community were assessed using principal response curves (PRC). Creosote induced a rapid, concentrationdependent reduction in zooplankton abundance and number of taxa, with maximum response (50,100% reduction in population densities) occurring between 5 and 7 d after treatment. Taxa that dominated at the time of treatment experienced the greatest impact, as indicated by large, positive species weight values (>1) from the PRC analysis. Many of these taxa recovered to pretreatment or control levels during the posttreatment period, with the degree and duration of recovery being strongly dependent on concentration. Creosote had little effect on species composition at less than 1.1 mg/L, because changes in the types and relative proportion of species contributed from Cladocera, Rotifera, and Copepoda were comparable to those observed in control microcosms. However, a significant shift in species composition was observed at concentrations greater than 1.1 mg/L; these microcosms were generally dominated by low numbers of rotifers, some of which had not been collected before treatment. Community-level effect concentrations (EC50s) were 44.6 and 46.6 ,g/L at 5 and 7 d, respectively, based on nominal creosote. Corresponding no-effect concentrations were 13.9 and 5.6 ,g/L. The results of this field study indicate that creosote may pose a significant risk to zooplankton communities at environmental concentrations potentially encountered during spills and/or leaching events. [source] The Janus-faced atracotoxins are specific blockers of invertebrate KCa channelsFEBS JOURNAL, Issue 16 2008Simon J. Gunning The Janus-faced atracotoxins are a unique family of excitatory peptide toxins that contain a rare vicinal disulfide bridge. Although lethal to a wide range of invertebrates, their molecular target has remained enigmatic for almost a decade. We demonstrate here that these toxins are selective, high-affinity blockers of invertebrate Ca2+ -activated K+ (KCa) channels. Janus-faced atracotoxin (J-ACTX)-Hv1c, the prototypic member of this toxin family, selectively blocked KCa channels in cockroach unpaired dorsal median neurons with an IC50 of 2 nm, but it did not significantly affect a wide range of other voltage-activated K+, Ca2+ or Na+ channel subtypes. J-ACTX-Hv1c blocked heterologously expressed cockroach large-conductance Ca2+ -activated K+ (pSlo) channels without a significant shift in the voltage dependence of activation. However, the block was voltage-dependent, indicating that the toxin probably acts as a pore blocker rather than a gating modifier. The molecular basis of the insect selectivity of J-ACTX-Hv1c was established by its failure to significantly inhibit mouse mSlo currents (IC50 , 10 ,m) and its lack of activity on rat dorsal root ganglion neuron KCa channel currents. This study establishes the Janus-faced atracotoxins as valuable tools for the study of invertebrate KCa channels and suggests that KCa channels might be potential insecticide targets. [source] Reproducibility of a microbial river water community to self-organize upon perturbation with the natural chemical enantiomers, R - and S -carvoneFEMS MICROBIOLOGY ECOLOGY, Issue 2 2008Katja Lehmann Abstract A river water microbial community was studied in response to perturbation with the monoterpene enantiomers R - and S -carvone. The microbial community structure and function was also evaluated after enantiomers exposure was switched. Microbial communities were evaluated by length heterogeneity PCR. The addition of R - and S -carvone enriched for a range of functionally different communities: enantiomer-selective, racemic and ones that contain both. After 5 days incubation, the R - and S -carvone treatments developed a range of dominant microbial communities, which were increasingly dissimilar from the ones in which no carvone degradation had taken place (R -values: R -carvone 0.743, S -carvone 0.5007). There was an increase in the evenness of the microbial community structure upon carvone depletion. After the cross-over, the rate of carvone utilization was significantly faster than after the first carvone addition (P=0.008) as demonstrated by concomitant carvone and oxygen depletion. The main R -degrading community (450,456 bp) appeared enantioselective and largely unable to degrade S -carvone, whereas the S -carvone-degrading community (502,508 bp) appeared to have racemic catabolic capacity. In conclusion, chemical perturbations, such as enantiomers, might generate a significant shift in the river microbial ecology that can have implications for the function of a river in both a spatial and temporal context. [source] Temperature-dependent changes in the soil bacterial community in limed and unlimed soilFEMS MICROBIOLOGY ECOLOGY, Issue 1 2003Marie Pettersson Abstract A humus soil with a pH(H2O) of 4.9 was limed to a pH of 7.5 and was incubated together with samples from unlimed and field limed (pH 6.1) soils at 5, 20 and 30°C for up to 80 days. The changes in the phospholipid fatty acid (PLFA) pattern were most rapid for the bacterial community of the soil incubated at 30°C, while no changes were found in the soil incubated at 5°C. The response of the community activity to temperature was measured using the thymidine incorporation method on bacteria extracted from the soil. The bacterial community in soil incubated at 30°C became more adapted to high temperature than that in soil samples incubated at 5°C. When soil samples incubated at 30°C and 20°C were returned to 5°C for 35 days, only small changes in the PLFA pattern were found. No significant shift in community temperature adaptation was found. Thus, higher temperatures (with higher turnover) led to higher rates of change in both the PLFA pattern and the activity response to temperature, compared with lower temperatures. No effect of liming as a way of increasing substrate availability and turnover on the rate of change was observed. Changes in the PLFA pattern appeared sooner than changes in the activity response to temperature, indicating that changes in the PLFA pattern were mainly due to phenotypic acclimation and not to species replacement. [source] Combination of rituximab with chemotherapy in diffuse large B-cell lymphoma.HEMATOLOGICAL ONCOLOGY, Issue 3 2008Evaluation in daily practice before, after approval of rituximab in this indication Abstract Randomized trials have demonstrated improved outcome from adding rituximab to CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) for patients with diffuse large B-cell lymphoma (DLBCL). This retrospective study compared the outcomes of 224 patients with DLBCL treated in our institution before (Period 1, 1996,2002) and after (Period 2, 2002,2005) approval of rituximab in this indication to evaluate the impact of the drug in daily practice in unselected patients receiving different types of chemotherapy. We treated 131 patients in Period 1 versus 93 in Period 2 (median follow-up, 75 and 29 months, respectively) with no difference in patient characteristics between the two periods. Event-free and overall survivals (EFS and OS) were significantly improved in Period 2 for elderly patients and a significant shift in the selection of regimens was observed at the time when rituximab became available. More patients received the CHOP regimen in Period 2 than in Period 1 (82 vs. 57%, p,<,0.007) with CHOP being substituted for epirubicin-based regimens. In younger patients treated mostly with the ACVBP regimen (doxorubicin, cyclophosphamide, vindesine, bleomycin, prednisone) these differences were not observed, suggesting that combination of rituximab with dose-dense chemotherapy may deserve further evaluation in this age group. Copyright © 2008 John Wiley & Sons, Ltd. [source] The renewed Lisbon Strategy and social exclusion policyINDUSTRIAL RELATIONS JOURNAL, Issue 6 2007Martina Dieckhoff ABSTRACT In the light of its manifest mid-term failure to make progress towards its key objectives, the EU introduced in 2005 a major ,relaunch' of its Lisbon Strategy for economic, employment and social development. The core aspect of this was ,prioritisation', involving an increased focus on growth and jobs. This raised the issue of whether the pursuit of greater competitiveness would lead to a downgrading of the importance of the original social objectives of the programme. In its focal concern on the fight against social exclusion, the EU's strategy involved both employment and social objectives. These emphasised in particular the creation not only of more but of ,better jobs' and the pursuit of actions to reinforce ,social inclusion' and ,social cohesion'. This article considers whether a significant shift did occur in policy emphasis and the implications of the Lisbon reform for progress in reducing the risks of social exclusion. It reviews first the basic changes in the formulation of the strategy and then examines in turn the effectiveness of its policy initiatives with respect to employment, the quality of work and social inclusion. [source] In situ methods of measurement,an important line of evidence in the environmental risk frameworkINTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT, Issue 2 2007Jim Wharfe Abstract A tiered framework provides a structured approach to assess and manage risk and underpins much of the legislation concerning chemicals and environmental management. Management decisions regarding appropriate controls can have high cost implications to the regulated community. The risk framework provides an evidence-based approach to reduce uncertainty in decision making. Traditional assessment is heavily dependent on laboratory-generated toxicity test data and estimations of exposure and effect. Despite many well documented demonstrations of in situ methodologies, they are rarely used by regulators to help improve assessment or to validate risk. Emerging legislation puts greater emphasis on environmental outcomes and represents a significant shift from the reliance on chemical measures alone toward biological responses that improve assessment and demonstrate ecological benefit. Diagnostic methods, that could include in situ-based measures, will help assess and manage environments failing to achieve good status and it is likely that a weight of evidence approach will be needed to help inform management decisions. The potential application of such measures in the risk framework is reviewed in the context of current and emerging legislation concerning chemicals. Effect measures on the basis of in situ methods provide an alternative line of evidence and can help reduce uncertainty in decision making. Criteria are presented to help select appropriate methods in a multiple-line, weight of evidence approach. [source] The Band Pass Filter*INTERNATIONAL ECONOMIC REVIEW, Issue 2 2003Lawrence J. Christiano We develop optimal finite-sample approximations for the band pass filter. These approximations include one-sided filters that can be used in real time. Optimal approximations depend upon the details of the time series representation that generates the data. Fortunately, for U.S. macroeconomic data, getting the details exactly right is not crucial. A simple approach, based on the generally false assumption that the data are generated by a random walk, is nearly optimal. We use the tools discussed here to document a new fact: There has been a significant shift in the money,inflation relationship before and after 1960. [source] Detecting trends in tropical rainfall characteristics, 1979,2003INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 8 2007K.-M. Lau Abstract Analyses of two state-of-the-art, blended space-based and ground-based global rainfall data sets from the Global Precipitation Climatology Project (GPCP) and the Climate Prediction Center Merged Analysis Product (CMAP) reveal that there was a significant shift in the probability distribution functions of tropical rainfall during the period 1979,2003. This shift features a positive trend in the occurrence of heavy (top 10% by rain amount) and light (bottom 5%) rain events in the tropics during 1979,2003 and a negative trend in moderate (25,75%) rain events. These trends are consistent in both data sets and are in overall agreement with the Climate Research Unit's (CRU) gauge-only rainfall data over land. The relationships among the trends and the possible long-term changes in rainfall characteristics are discussed. Copyright © 2006 Royal Meteorological Society [source] North American weather-type frequency and teleconnection indicesINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 1 2003Scott C. Sheridan Abstract The impact of teleconnections upon the surface climate has largely been examined via a response in monthly mean temperature or total precipitation. In this paper, a different approach is undertaken, by examining the response of synoptic weather-type frequencies to different teleconnection phases. For over 330 stations in the USA and Canada, the Spatial Synoptic Classification scheme has classified each day in each station's period of record into one of seven weather-type categories, based on thermal, moisture, and other characteristics. The differences in how frequently these different weather types occur in different phases of the North Atlantic Oscillation (NAO) and Pacific,North American (PNA) teleconnection patterns is assessed, for Canadian stations from 1953 to 1993, and for US stations from 1950 to 1999. For PNA, a significant shift in the transitional frequency is observed, suggesting changes in storm track. Concomitantly, a large shift in Dry Polar and Moist Tropical frequencies is observed across the continent. Across the West, in +PNA wintertime months far fewer Dry Polar days are observed. Across the eastern USA, these polar intrusions are more common, and Moist Tropical is diminished significantly. The frequency of the transitional situation is also correlated with NAO phase, with differences as large as a factor of two across much of Canada and the northern USA. In northeastern Canada, there is a large replacement of Moist Polar conditions with Dry Polar conditions during +NAO. Farther south, however, across the eastern USA, both polar weather types occur much less often with +NAO. Although previous research has discovered eastern North American connections to the NAO, this research has shown that the connections often extend into the interior West during much of the year. Particularly strong in the spring, Dry Tropical conditions are much more common with +NAO throughout much of the continent, as far west as the Great Basin. Copyright © 2003 Royal Meteorological Society. [source] Fluctuation in Autonomic Tone is a Major Determinant of Sustained Atrial Arrhythmias in Patients with Focal Ectopy Originating from the Pulmonary VeinsJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 3 2001MARC ZIMMERMANN M.D. Autonomic Variations in Focal AF. Introduction: This study was designed to analyze dynamic changes in autonomic tone preceding the onset of sustained atrial arrhythmias in patients with focal atrial fibrillation (AF) to determine why patients with frequent discharge from the arrhythmogenic foci develop sustained AF. Methods and Results: Holter tapes from 13 patients (10 men and 3 women; mean age 53 ± 5 years) with paroxysmal "lone" AF (mean 18 ± 13 episodes per week) and a proven focal origin (pulmonary veins in all cases) were analyzed. A total of 38 episodes of sustained AF (> 30 min) were recorded and submitted to frequency-domain heart rate variability analysis. Six periods were studied using repeated measures analysis of variance: the 24,hour period, the hour preceding AF, and the 20 minutes before AF divided into four 5,minute periods. A significant increase in high-frequency (HF, HF-NU) components was observed during the 20 minutes preceding AF (P = 0.003 and 0.002, respectively), together with a progressive decrease in normalized low-frequency (LF-NU) components (P = 0.035). An increase in LF/HF ratio followed by a linear decrease starting 15 minutes before sustained AF also was observed, indicating fluctuations in autonomic tone, with a primary increase in adrenergic drive followed by a marked modulation toward vagal predominance immediately before AF onset. Conclusion: In patients with focal ectopy originating from the pulmonary veins, sustained episodes of atrial arrhythmias are mainly dependent on variations of autonomic tone, with a significant shift toward vagal predominance before AF onset. [source] Interactions between the stem-mining weevils Ceutorhynchus napi Gyll. and Ceutorhynchus pallidactylus (Marsh.) (Coleoptera: Curculionidae) in oilseed rapeAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 3 2004Georg Dechert Abstract 1,The rape stem weevil Ceutorhynchus napi Gyll. and the cabbage stem weevil Ceutorhynchus pallidactylus (Marsh.) share the same habitat and food resource within the stems of oilseed rape, Brassica napus L. var. oleifera. Interactions occurring between these two sympatric species on this host were studied under both field and laboratory conditions. 2,The oviposition preference of C. pallidactylus and the within-plant distribution of eggs and larvae were examined in field plots of oilseed rape. Female C. pallidactylus tended to lay their eggs in plants already infested by eggs and larvae of C. napi rather than in uninfested plants. The within-plant distribution of the egg batches of C. pallidactylus did not differ significantly between uninfested plants and those preinfested by C. napi. Ovipositing females of C. napi and C. pallidactylus generally showed a significant preference for plants with larger stem diameter. 3,Laboratory choice tests provided further evidence for the oviposition preference of C. pallidactylus. Females laid significantly more eggs in leaves of plants that had been previously infested by C. napi than in leaves of previously uninfested plants. 4,Larvae of C. pallidactylus showed a significant shift of their feeding niche towards the stem base when feeding in individual plants attacked by both species. This possibly indicates ressource partitioning between C. pallidactylus and C. napi. The within-plant distribution of C. napi larvae was not affected by the simultaneous attack of C. pallidactylus. 5,The size of the head capsule of full-grown larvae of C. napi and C. pallidactylus was not significantly correlated with the diameter of the stem of their host plant or with the number of conspecific larvae within individual plants. [source] Economic development, institutional change, and the political economy of agricultural protection An econometric study of Belgium since the 19th centuryAGRICULTURAL ECONOMICS, Issue 1 2001Johan F.M. Swinnen Abstract This empirical study uses 100 years of annual data on 11 agricultural commodities from Belgium to measure the impact of structural changes coinciding with economic development and changes in political institutions on agricultural protection. The analysis shows that changes in agricultural protection are caused by a combination of factors. Governments have increased protection and support to farmers when world market prices for their commodities fell, and vice versa, offsetting market effects on producer incomes. Other economic determinants were the share of the commodities in total consumer expenditures (negative effect) and in total output of the economy (positive effect). With Belgium a small economy, there was no impact of the trade position. Changes in political institutions have affected agricultural protection. Democratic reforms which induced a significant shift in the political balance towards agricultural interests, such as the introduction of the one-man-one-vote system, led to an increase in agricultural protection. The integration of Belgian agricultural policies in the Common Agricultural Policy in 1968 coincided with an increase in protection, ceteris paribus. Both institutional factors, related to changes in access to and information about the decision-making at the EU level, and structural changes in the agricultural and food economy may explain this effect. [source] ,Care': Moral concept or merely an organisational suffix?JOURNAL OF INTELLECTUAL DISABILITY RESEARCH, Issue 7 2008J. Clapton Abstract Background Over recent decades, a couple of interesting trends have occurred in regard to human services practices in Australia. First, there has been a significant shift from practices that previously have intentionally responded to emerging and continuing human need within communities to practices that are now managed within a context of managerialism and influenced by market forces. Second, in such a changing context, increasingly, organisations have added the suffix ,care' to their organisational name. One is therefore left to consider why this latter change has occurred, and how is care being considered, particularly in organisations supporting people with intellectual disability (ID). Method A conceptual-theoretical analysis is undertaken to explore the characteristics of human services that embrace managerialism. The moral constructions of personhood in regard to people with ID within this service context are investigated; and the implications of how care is practised are considered. Results An immoral-amoral binary of personhood within an underpinning neo-liberal context is identified and analysed. Further analysis reveals a more insidious independent,dependent binary for people with an ID linked to a dominating Ethic of Normalcy. This latter binary suggests that care seemingly becomes neither ethically relevant nor legitimate for people with ID in managerialist service contexts. Conclusions Ethical transformation in regard to care is needed for contemporary human services practice for people with ID. The underpinning Ethic of Normalcy is challenged for an Ethic of Engagement; whereby a deep understanding of care as a moral concept needs to be at the core of practice, rather than merely attached in an organisational name. [source] Applications of time-resolved resonance energy transfer measurements in studies of the molecular crowding effect,JOURNAL OF MOLECULAR RECOGNITION, Issue 5 2004Varda Ittah Abstract The native structures of many globular proteins are only weakly stabilized and form in solution ensembles of multiple conformers. The energy differences between the conformers are assumed to be small. This is the case of flexible multidomain proteins where domain motions were observed. High concentrations of inert macrosolute, which create a crowded or confined environment, can cause shifts of the distribution of the conformers of such proteins towards the more compact structures. This effect may also promote compact structures in partially folded proteins. Time-resolved dynamic non-radiative excitation energy transfer (tr-RET) is suitable for detection of either subtle or major changes in distributions of intramolecular distances in protein molecules in solutions. Two experiments were performed which demonstrated the applicability of tr-RET for detection of the effect of macrosolutes on the conformational ensembles of flexible states of protein molecules. The distribution of distances between residues 203 and 169 in the CORE domain of E. coli adenylate kinase (AK) in the denatured state was determined in the presence of high concentrations of dextran 40. A significant shift of the mean of the distribution was observed without reduction of its width. This was interpreted as a shift to compact structure without change of the degree of disorder of the chain. In a second experiment the distribution of the distance between residues 55 and 169 in AK, which spans the cleft between the CORE and the AMPbind domains, was monitored. No clear effect of high concentrations of dextran 40 was found. These experiments show the strength of the application of tr-RET in investigation of changes in the sub-states of flexible conformations of globular protein. Networks of pairs of labeled sites can be prepared and tr-RET experiments can be performed in order to search for the segments of the protein molecules, which respond to the presence of inert macromolecules in their environment. Copyright © 2004 John Wiley & Sons, Ltd. [source] Substituent effects in solvolysis of 1,1-diphenylethyl p -nitrobenzoates.JOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 8 2002Symmetrically disubstituted, monosubstituted systems Abstract The rates of solvolysis of 1,1-diarylethyl p -nitrobenzoates and chlorides were determined conductimetrically at 25,°C in 80% (v/v) aqueous acetone. Applying the Yukawa,Tsuno (Y,T) equation, the symmetrical (X,=,Y) subseries gave a precise additivity relationship for the whole substituent range with a ,sym value of ,3.78 and an rsym value of 0.77. While any Y subsets gave statistically less reliable Y,T correlations, the apparent , value changed significantly depending on the fixed Y substituents; the , value decreases with the more electron-donating fixed substituents Y, which is compatible with the Hammond shift of the transition state coordinate. Nevertheless, the concave correlations of the More O'Ferrall non-linearity relationship for any Y subsets are not in line with what is expected from the reactivity,selectivity relationship suggesting an anti-Hammond shift of transition state. However, we found a precise extended Brønsted relationship between the pK values of 1,1-diarylethylenes and solvolysis rate process with a constant slope of ,,=,1.03,±,0.03. This is direct evidence indicating that there is no significant shift of the transition-state coordinate over the whole range of substituent change. Copyright © 2002 John Wiley & Sons, Ltd. [source] Consumer participation in mental health services: looking from a consumer perspectiveJOURNAL OF PSYCHIATRIC & MENTAL HEALTH NURSING, Issue 4 2003J. LAMMERS rn bed mba phd Widespread changes to the structure and delivery of mental health services have effected considerable change in the role of the service user or consumer. The view of consumers of mental health services as passive recipients of care and treatment is gradually undergoing a significant shift, in light of an increasing expectation that consumers be provided with opportunities to become actively involved in all aspects of their care. Consumer participation is now broadly reflected in government policy; however, to date there has been little exploration of the extent to which the policy is being realized in practice. To provide a greater understanding of these experiences and opinions, in-depth interviews were conducted with consumers of mental health services (n = 15). The interview transcripts were analysed through the identification and explication of major themes. The findings reinforce the need to view consumers as heterogenous and respond to individual needs and interests regarding consumer participation. Despite variations in experience there is a clear need to develop mechanisms to support consumer involvement and to influence the attitudes of health professions to become more valuing of a consumer perspective. Nurses are in an ideal position to lead this process. [source] Seeking a Holocene drift ice proxy: non-clay mineral variations from the SW to N-central Iceland shelf: trends, regime shifts, and periodicities,JOURNAL OF QUATERNARY SCIENCE, Issue 7 2009John T. Andrews Abstract Quantitative X-ray diffraction analysis of the <2,mm sediment fraction was carried out on 1257 samples (from the seafloor and 16 cores) from the Iceland shelf west of 18° W. All but one core (B997-347PC) were from transects along troughs on the NW to N-central shelf, an area that in modern and historic times has been affected by drift ice. The paper focuses on the non-clay mineralogy of the sediments (excluding calcite and volcanic glass). Quartz and potassium feldspars occupy similar positions in an R-mode principal component analysis, and oligoclase feldspar tracks quartz; these minerals are used as a proxy for ice-rafted detritus (IRD). Accordingly, the sum of these largely foreign minerals (Q&K) (to Icelandic bedrock) is used as a proxy for drift ice. A stacked, equi-spaced 100 a record is developed which shows both low-frequency trends and higher-frequency events. The detrended stacked record compares well with the flux of quartz (mg,cm,2,a,1) at MD99-2269 off N Iceland. The multi-taper method indicated that there are three significant frequencies at the 95% confidence level with periods of ca. 2500, 445 and 304 a. Regime shift analysis pinpoints intervals when there was a statistically significant shift in the average Q&K weight %, and identifies four IRD-rich events separated by intervals with lower inputs. There is some association between peaks of IRD input, less dense surface waters (from ,18O data on planktonic foraminifera) and intervals of moraine building. Copyright © 2009 John Wiley & Sons, Ltd. [source] The analysis of pH-dependent protonated conformers of 1-hydroxyethylidene-1,1-diphosphonic acid by means of FT-Raman spectroscopy, multivariate curve resolution and DFT modellingJOURNAL OF RAMAN SPECTROSCOPY, Issue 12 2009Werner Barnard Abstract 1-Hydroxyethylidene-1,1-diphosphonic acid (HEDP) solutions in the pH range 0.98,13.00 were analysed using FT-Raman spectroscopy and 31P and 23Na NMR spectroscopy. Vibrational bands for different protonated species were observed in the Raman spectra, whereas only a single NMR signal that shifted with pH was observed for all samples over the entire pH range. No significant shift in the 23Na NMR signal was observed, confirming that formation of Na+(aq) complexes did not take place; hence, no interference with the different protonated forms of HEDP occurred. Vibrational bands were assigned using density functional theory(DFT)-calculated spectra of the most likely conformers in solution. Multivariate curve resolution was performed on the Raman spectra in the region containing the PO stretching vibrations to determine the number of protonated species formed over the entire pH range. Chemometric analysis compares very favourably with the experimental species distribution diagram which was generated using the reported log KH values. Copyright © 2009 John Wiley & Sons, Ltd. [source] Effect of gluten content on recrystallisation kinetics and water mobility in wheat starch gelsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 4 2004Xin Wang Abstract The effect of gluten on starch retrogradation at 5 °C was studied using 1H NMR relaxometry. Gels were made from gluten and starch at 27.8 and 38.5% total solids and with gluten comprising either 10, 15 or 20% of the solids. Changes in the transverse relaxation time constant (T2) were related to water mobility. Mono-exponential analysis of relaxation curves showed that, in general, gluten retarded starch retrogradation. T2 values in gluten gels also decreased during storage, but to a much lesser extent. Distributed exponential analysis showed that two distinct regions of T2 were observed in all samples. During aging, the peak values of both regions shifted to lower values for all gels. Starch gel samples showed the most significant shift, and gluten gels showed the least. The three levels of gluten addition in starch/gluten gels produced similar shifts. For all samples the signal intensity of the less mobile region decreased more dramatically than that of the more mobile region during storage. It was suggested that gluten retards water loss in the granule remnants. Copyright © 2004 Society of Chemical Industry [source] Elucidation of spermidine interaction with nucleotide ATP by multiple NMR techniquesMAGNETIC RESONANCE IN CHEMISTRY, Issue 2 2010Zhiyan Song Abstract Interaction of polyamines with nucleotides plays a key role in many biological processes. Here we use multiple NMR techniques to characterize interaction of spermidine with adenosine 5,-triphosphate (ATP). Two-dimensional 1H- 15N spectra obtained from gs-HMBC experiments at varied pH show significant shift of N-1 peak around pH 2.0,7.0 range, suggesting that spermidine binds to N-1 site of ATP base. The binding facilitates N-1 deprotonation, shifting its pKa from 4.3 to 3.4. By correlating 15N and 31P chemical shift data, it is clear that spermidine is capable of concurrently binding to ATP base and phosphate sites around pH 4.0,7.0. The self-diffusion constants derived from 1H PFG-diffusion measurements provide evidence that binding of spermidine to ATP is in 1:1 ratio, and pH variations do not induce significant nucleotide self-association in our samples. 31P spectral analysis suggests that at neutral pH, Mg2+ ion competes with spermidine and shows stronger binding to ATP phosphates. From 31P kinetic measurements of myosin-catalyzed ATP hydrolysis, it is found that binding of spermidine affects the stability and reactivity of ATP. These NMR results are important for advancing the studies on nucleotide,polyamine interaction and its impact on nucleotide structures and activities under varied conditions. Copyright © 2009 John Wiley & Sons, Ltd. [source] Increase in the use of rebreathing gas flow systems and in the utilization of low fresh gas flows in Finnish anaesthetic practice from 1995 to 2002ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 3 2005H. Tohmo Background:, The use of rebreathing systems together with low fresh gas flows saves anaesthetic gases, reduces the costs of anaesthesia, causes less environmental and ergonomic adverse effects, i.e. less air contamination in the operating room, and has favourable physiological effects. We assessed whether the use of non-rebreathing vs. rebreathing gas flow systems and high vs. lower fresh gas flows has changed during recent years. Methods:, The use of rebreathing and non-rebreathing systems and the utilization of fresh gas flows were evaluated by sending a questionnaire to the heads of anaesthesia departments at all public health care hospitals in Finland in 1996 and 2003. The data was gathered from the previous years 1995 and 2002, respectively. Results:, The use of rebreathing systems increased from 62% to 83% of all instances of general anaesthesia (P < 0.001). In rebreathing gas flow systems, there was a significant shift from high fresh gas flows (3 l min,1 and more) towards lower fresh gas flows (between 1 to 2 l min,1 and even below 1 l min,1) (P < 0.001). Conclusions:, The benefits of low fresh gas flows have now been achieved in most instances of rebreathing system anaesthesia, which was not the case in 1995. [source] Rethinking Research Ethics in Contemporary Applied Linguistics: The Tension Between Macroethical and Microethical Perspectives in Situated ResearchMODERN LANGUAGE JOURNAL, Issue 4 2008MAGDALENA KUBANYIOVA The prominent current tendency in applied linguistics to situate its theory and research has seen parallel shifts in the type of research methodologies being employed. Increasingly, decontextualized laboratory methodologies are giving way to more holistic approaches, and these, in turn, involve a significant shift in the researchers' roles, relationships, and ethical responsibilities. By providing examples of specific ethical dilemmas that arose in the process of a longitudinal classroom-based research project, I aim to illustrate that adherence to general "macroethical" principles established in professional codes of ethics may be inadequate for ensuring ethical research in the situated era, which warrants the expansion of the ethical lenses and consideration of alternative microethical models. I conclude with a call for developing a more contextualized code of practice that would integrate both perspectives and recognize the ability to reflect on the ethical consequences of research practice as a core competence of applied linguists. [source] Correlation between energy usage and the rate of economic developmentOPEC ENERGY REVIEW, Issue 1 2006Salman Saif Ghouri This paper reviews the correlation between per capita GDP and per capita consumption of different sources of energy for OPEC Member Countries, the G-7 and three Asian countries, both with and without natural logarithm. In addition, the paper estimates the ratios for total GDP and total energy consumption of different sources of energy and also estimates GDP energy consumption elasticities. The paper concludes that on a per capita basis most OPEC Countries exhibit negative and weak relationships for all forms of energy, including electricity. For the G-7 and Asian countries, this relationship is positive and strong, with the exception of oil for G-7 countries, where there is a weak correlation. Surprisingly, most OPEC Countries showed a comparatively strong and positive correlation when tested for total GDP in relation to total energy consumption of the respective energy sources. The relationship for the rest of the countries remains unchanged. Population might have distorted the results in OPEC Countries. These results suggest that one should be cautious when drawing conclusions and not ignore the aggregate comparison, as this could otherwise lead to wrong results. For G-7 countries, there has been a significant shift in the pattern of energy consumption in relation to GDP when comparing 1960,73 and 1973,2001. All adjusted downward in the later period. However, the greatest adjustment was associated with petroleum consumption. The general conclusion is that wealth creation in G-7 countries is directly associated with the efficient use of all forms of energy. In contrast, most OPEC Countries exhibit a weaker linkage between energy consumption and economic development on a per capita basis, probably due to inefficient usage of resources or due to disproportionate distribution of wealth and thus energy usage. [source] Complement analysis in children with idiopathic membranoproliferative glomerulonephritis: A long-term follow-upPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 3 2001Rainer Schwertz Fifty children with idiopathic membranoproliferative glomerulonephritis (MPGN), aged 2,14 years at apparent onset, were monitored for the presence of C3 nephritic factor (C3 NeF) and signs of complement activation in serum. In addition, C3 allotyping was performed in 32 patients. Observation time ranged from 2 to 20 (median 11) years. C3 NeF activity was detected at least once in 60% of the patients (in 11 of 26 with type I, in 15 of 17 with type II, and in four of seven with type III). C3 NeF-positive patients had significantly reduced levels of CH50 and C3 and elevated levels of C3dg/C3d. During follow-up, C3 levels were persistently normal in 62% of the patients with MPGN type I and in 43% with type III but in only 18% with type II. C3 allotype frequencies differed from those found in healthy controls with a significant shift to the C3F/C3FS variants in C3 NeF-positive patients. C3b(Bb)P as a marker for alternative pathway activation was not increased in C3 NeF-positive patients. Despite the presence of C3 NeF activity, C3 levels remained normal in six patients throughout the observation period. C3 NeF became undetectable in six patients, whereas seven developed C3 NeF activity during follow-up. There was no significant difference in renal survival probability in patients with or without C3 NeF activity. Neither C3 variants nor continous low C3 or low CH50 levels had any prognostic value for the clinical outcome. No factor H deficiency was detected. [source] Party Identification in Emotional and Political Context: A ReplicationPOLITICAL PSYCHOLOGY, Issue 6 2007Francis Neely While testing an affective measure of party identification Burden and Klofstad (2005) found that using the phrase, "feel that you are," in place of, "think of yourself as," significantly shifted PID in a Republican direction. I adopt the theoretical framework of Affective Intelligence (Marcus, Neuman, & MacKuen, 2000) to specify how the timing of their question-wording experiment may have influenced the results. I suggest that the outcome was a function of (a) anxiety present during the survey, which ran just after 9/11 of 2001, coupled with (b) a political environment that favored Republicans. In a 2005 survey I replicate the experiment and collect new measures with which to test expectations. I find no significant shift in PID, and provisional support for the Affective Intelligence explanation. The results validate Burden and Klofstad's measure, qualify their findings, and test the application of the theory of Affective Intelligence to party dispositions. Alternative explanations and directions for further research are discussed. [source] Poverty And Worklessness In Britain*THE ECONOMIC JOURNAL, Issue 494 2004Stephen Nickell Relative poverty in the UK has risen massively since 1979 mainly because of increasing worklessness, rising earnings dispersion and benefits indexed to prices, not wages. The economic force underlying this is the significant shift in demand against the unskilled. This has substantially weakened the low-skill labour market which has increased both pay dispersion and worklessness, particularly among low-skilled men. Practical policies discussed include improving education and overall well-being for children in the lower part of the ability range, raising wage floors, New Deal policies, tax credits and benefits for the workless. 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