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  • 1
    Language: English
    In: Journal of the American Chemical Society, 22 August 2012, Vol.134(33), pp.13902-11
    Description: Second-order rate constants k(2) for the reactions of various donor- and acceptor-substituted benzhydrylium ions Ar(2)CH(+) with π-nucleophiles in CH(2)Cl(2) were determined by laser flash irradiation of benzhydryl triarylphosphonium salts Ar(2)CH-PAr(3)(+)X(-) in the presence of a large excess of the nucleophiles. This method allowed us to investigate fast reactions up to the diffusional limit including reactions of highly reactive benzhydrylium ions with m-fluoro and p-(trifluoromethyl) substituents. The rate constants determined in this work and relevant literature data were jointly subjected to a correlation analysis to derive the electrophilicity parameters E for acceptor-substituted benzhydrylium ions, as defined by the linear free energy relationship log k(2)(20 °C) = s(N)(N + E). The new correlation analysis also leads to the N and s(N) parameters of 18 π-nucleophiles, which have only vaguely been characterized previously. The correlations of log k(2) versus E are linear well beyond the range where the activation enthalpies ΔH(++) of the reactions are extrapolated to reach the value of ΔH(++) = 0, showing that the change from enthalpy control to entropy control does not cause a bend in the linear free energy relationship, a novel manifestation of the compensation effect. A flattening of the correlation lines only occurs for k(2) 〉 10(8) M(-1) s(-1) when the diffusion limit is approached.
    Keywords: Gibbs' Free Energy -- Measurement ; Benzene -- Chemical Properties ; Electrodiffusion -- Analysis ; Methyl Compounds -- Chemical Properties ; Nucleophiles -- Chemical Properties ; Substitution Reactions -- Analysis;
    ISSN: 00027863
    E-ISSN: 1520-5126
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  • 2
    Language: English
    In: Conservation biology : the journal of the Society for Conservation Biology, February 2013, Vol.27(1), pp.155-65
    Description: Management-effectiveness scores are used widely by donors and implementers of conservation projects to prioritize, track, and evaluate investments in protected areas. However, there is little evidence that these scores actually reflect the capacity of protected areas to deliver conservation outcomes. We examined the relation between indicators of management effectiveness in protected areas and the effectiveness of protected areas in reducing fire occurrence in the Amazon rainforest. We used data collected with the Management Effectiveness Tracking Tool (METT) scorecard, adopted by some of the world's largest conservation organizations to track management characteristics believed to be crucial for protected-area effectiveness. We used the occurrence of forest fires from 2000 through 2010 as a measure of the effect of protected areas on undesired land-cover change in the Amazon basin. We used matching to compare the estimated effect of protected areas with low versus high METT scores on fire occurrence. We also estimated effects of individual protected areas on fire occurrence and explored the relation between these effects and METT scores. The relations between METT scores and effects of protected areas on fire occurrence were weak. Protected areas with higher METT scores in 2005 did not seem to have performed better than protected areas with lower METT scores at reducing fire occurrence over the last 10 years. Further research into the relations between management-effectiveness indicators and conservation outcomes in protected areas seems necessary, and our results show that the careful application of matching methods can be a suitable method for that purpose.
    Keywords: Conservation of Natural Resources ; Fires
    ISSN: 08888892
    E-ISSN: 1523-1739
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  • 3
    Language: English
    In: World Development, Dec, 2014, Vol.64, p.654(15)
    Description: To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.worlddev.2014.06.028 Byline: Kerstin Nolte, Lieske Voget-Kleschin Abstract: acents We propose a framework for consultation for land acquisitions. acents We test this framework for de jure and de facto consultation in Mali. acents Our framework can be used to analyze consultative processes elsewhere. acents If background injustices exist regulatory changes are necessary. Article History: Accepted 30 June 2014
    ISSN: 0305-750X
    Source: Cengage Learning, Inc.
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  • 4
    Language: English
    In: Molecular ecology, May 2011, Vol.20(9), pp.1803-4
    Description: Invasive species receive attention as manifestations of global ecological change and because of the effects that they may have on other organisms. They are commonly discussed in the context of the ecological perturbations or the human activities that permitted the invasion. There is also evidence, that there is an intrinsic component to biological invasions in that evolutionary changes of the invaders themselves can facilitate or limit invasions (Lee 2002; Urban et al. 2007; Van Bocxlaer et al. 2010). Hence, teasing apart whether environmental change or changes of the organism foster invasions is an interesting field of research. Ample evidence for plants and animals documents that ecological change and human activities trigger range expansions and invasions, but questions regarding evolutionary change of invaders remain less explored although there are several reasons to believe it matters. Firstly, rapid evolutionary change is possible in time-frames relevant for contemporary biological invasions(Hendry et al. 2007). Furthermore, population genetic modelling suggests that there are circumstances where the range expansion and colonization of empty spaces in the course of an invasion can induce evolutionary change in a way that is specific to invaders: the process of repeated founding out of marginal populations in the course of a range expansion can shift allele frequencies and has been referred to as allele surfing, which not only affects neutral genetic variance, but also fitness relevant traits (Klopfstein et al. 2006; Travis et al. 2007; Burton & Travis 2008). Importantly, this process poses a null model for evolutionary inference in invasive populations. It predicts conspicuous allele frequency changes in an expanding metapopulation unless migration homogenizes the gene pool. Despite this relevance, ideas about allele surfing rely heavily on modelling although some experimental evidence comes from studies that document the segregation of genetic variants in growing plaques of bacteria (Hallatschek et al. 2007). To date, little empirical data is available that would reveal the migration processes that affect the establishment of gene pools at invasion fronts in natural systems. This aspect sets the study of Bronnenhuber et al. (2011) apart. They quantify migration behind the expansion front of an invading fish and thus provide important baseline data for the interpretation of the emerging patterns of genetic differentiation.
    Keywords: Biological Evolution ; Introduced Species ; Population Dynamics
    ISSN: 09621083
    E-ISSN: 1365-294X
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  • 5
    Language: English
    In: Proceedings of the National Academy of Sciences of the United States, March 26, 2013, Vol.110(13), p.4956(6)
    Description: Protected areas in tropical countries are managed under different governance regimes, the relative effectiveness of which in avoiding deforestation has been the subject of recent debates. Participants in these debates answer appeals for more strict protection with the argument that sustainable use areas and indigenous lands can balance deforestation pressures by leveraging local support to create and enforce protective regulations. Which protection strategy is more effective can also depend on (i) the level of deforestation pressures to which an area is exposed and (ii) the intensity of government enforcement. We examine this relationship empirically, using data from 292 protected areas in the Brazilian Amazon. We show that, for any given level of deforestation pressure, strictly protected areas consistently avoided more deforestation than sustainable use areas. Indigenous lands were particularly effective at avoiding deforestation in locations with high deforestation pressure. Findings were stable across two time periods featuring major shifts in the intensity of government enforcement. We also observed shifting trends in the location of protected areas, documenting that between 2000 and 2005 strictly protected areas were more likely to be established in high-pressure locations than in sustainable use areas and indigenous lands. Our findings confirm that all protection regimes helped reduce deforestation in the Brazilian Amazon. www.pnas.org/cgi/doi/10.1073/pnas.1214786110
    Keywords: Deforestation -- Research ; Deforestation -- Environmental Aspects
    ISSN: 0027-8424
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  • 6
    Language: English
    In: Health policy, 2011, Vol.103(1), pp.47-52
    Description: There has been growing interest in the comparison of health system performance within and between countries, using a range of different indicators. This study examines trends in amenable mortality, as one measure of health system performance, in sixteen high-income countries. Amenable mortality was defined as premature death from causes that should not occur in the presence of timely and effective health care. We analysed age-standardised rates of amenable mortality under age 75 in 16 countries for 1997/1998 and 2006/2007. Amenable mortality remains an important contributor to premature mortality in 16 high-income countries, accounting for 24% of deaths under age 75. Between 1997/1998 and 2006/2007, amenable mortality fell by between 20.5% in the US and 42.1% in Ireland (average decline: 31%). In 2007, amenable mortality in the US was almost twice that in France, which had the lowest levels. Amenable mortality continues to fall across high-income nations although the USA is lagging increasingly behind other high income countries. Despite its many limitations, amenable mortality remains a useful indicator to monitor progress of nations.
    Keywords: Population Health ; Health System Performance ; Amenable Mortality ; Cross-National Comparison ; Public Health
    ISSN: 0168-8510
    E-ISSN: 1872-6054
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  • 7
    Language: English
    In: Journal of the American Chemical Society, 20 June 2012, Vol.134(24), pp.9894-7
    Description: Polymersomes assembled from amphiphilic block copolymers containing a glassy hydrophobic segment can be further re-engineered to perform a controlled shape transformation from a thermodynamically stable spherical morphology to a kinetically trapped stomatocyte structure. The stable bowl-shape stomatocyte morphology is ideal for the specific physical entrapment of nanoparticles for potential use in heterogeneous catalysis and drug delivery. Herein we report two approaches to obtain a selective and controlled entrapment of platinum nanoparticles (PtNP) of different sizes and shapes inside the stomatocyte structure. In the first approach, the stomach of the stomatocytes is used to template the growth of the PtNP by controlling and confining the nucleation points inside the cavity. In the second method, preformed nanoparticles are engulfed during the stomatocyte formation process. Synergistically, the reverse effect is observed, that is, differently shaped nanoparticles were shown to exhibit a templating effect on the stomach formation of the stomatocytes.
    Keywords: Nanoparticles -- Chemistry ; Platinum -- Chemistry ; Polymers -- Chemistry
    ISSN: 00027863
    E-ISSN: 1520-5126
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  • 8
    Article
    Article
    British Medical Journal Publishing Group
    Language: English
    In: BMJ, 11 September 2017, Vol.358
    Description: Education and training of the workforce is crucial but so is the wider policy framework that influences behaviours
    Keywords: Behavior ; Health Education ; Professionals ; Medical Personnel ; Stakeholders ; Holistic Medicine ; Skills for Health ; Health Education England;
    ISSN: 0959-8138
    ISSN: 09598138
    E-ISSN: 1756-1833
    E-ISSN: 17561833
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  • 9
    Language: English
    In: Journal of Strength and Conditioning Research, 2015, Vol.29(11), p.S88(6)
    Description: Hands-free hydration systems are often advocated for improved hydration and performance in military populations. The aim was to assess whether such systems indeed result in Improved hydration in exercising soldiers. Subjects were required to complete a route march while consuming water ad libitum from either a hydration bladder (BG) or traditional canteen (CG). Water intakes of 538 ml x [h.sup.-1] (BG) and 533 ml x [h.sup.-1] (CG) resulted In no differences for changes In body mass, serum [[Na.sup.+]], plasma osmolality, total body water, or time required to complete the march. There were no differences between peak exercise core temperature of the BG (38.9[degrees]C) and CG (38.7[degrees]C) groups. There were no differences between the groups for fluid balance, thermoregulation, or performance. This is a not a surprising finding because the amount of fluid consumed ad libitum is determined by changes in serum osmolality and not the fluid delivery system as often proposed. Key Words water-electrolyte balance, body temperature regulation, canteen, water bladder
    Keywords: Electrolytes – Measurement ; Body Temperature – Measurement ; Drinking (Physiology) – Methods ; Drinking (Physiology) – Equipment and Supplies
    ISSN: 1064-8011
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  • 10
    Language: English
    In: The Lancet, 03 November 2018, Vol.392(10158), pp.1604-1605
    Description: In 1871, the average newborn girl would live about 45 years (vs 41 years for boys); by 2016, this life expectancy had almost doubled to 83 years (vs 79 years for boys).3 Much of this increase in life expectancy was, at least initially, due to improvements in public health, such as the provision of clean...
    Keywords: Medicine
    ISSN: 0140-6736
    E-ISSN: 1474-547X
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