323,233 research outputs found
Ecosystem Services in Farmland and Cities
No full textEngineered ecosystems from farmland and cities are the most important providers of ecosystem services (ES) for the world population. This chapter discusses the concept of ES, their valuation methods, the types of engineered systems and how ES can be adopted by them to enhance them and ensure an equitable and sustainable future. The ES framework has been increasingly used to explain the interactions between ecosystems and human well-being. The Millennium Ecosystem Assessment (MEA) assessed the consequences of ecosystem change for human well-being and provided a framework to identify and classify ES. It established the scientific basis for actions needed to balance nature and human well-being by sustainable use of ecosystems. The chapter follows MEA typology and discusses the ES approach and ecosystem-based adaptation. The ES challenges within cities are enormous and are discussed in the chapter
Improved fitness of aphid parasitoids receiving resource subsidies
No full textThe availability of nonhost resource subsidies affects the ability of parasitoids to overcome egg and time limitation and maximize lifetime reproductive success. We combined field and laboratory experiments to examine the effects of floral resource subsidies on the reproductive fitness of aphid parasitoids. Under controlled laboratory conditions, sugar resources significantly increased longevity and potential fecundity (egg load) in the endoparasitoids Aphidius rhopalosiphi and Diaeretiella rapae (Hymenoptera: Aphidiidae). Laboratory microcosm experiments showed that increased potential fecundity translated into significantly higher realized fecundity (i.e., rates of aphid parasitism) by A. rhopalosiphi receiving resource subsidies. Mechanisms of enhanced realized fecundity also operated under natural field conditions. Replicated field experiments on cultivated wheat, with host density controlled by experimental placement of aphids, showed that, in general, proximity to floral resource patches significantly increased rates of parasitism. Parasitism rates declined exponentially with increasing distance from floral patches, reaching zero beyond 14 m. Increased potential fecundity reduces the chances of parasitoids becoming egg-limited, whereas increased longevity reduces the chances of parasitoids becoming time-limited during host oviposition. Although the plasticity of egg load and longevity observed under varying conditions of resource availability is probably more relevant to parasitoid evolution, the individual fitness benefits from ephemeral resource patches are certainly important in the ecological enhancement of biological control agents
An overview of haemodialysis and oxidant stress
No full textToday's patient population is increasingly older. Patients with chronic renal failure therefore start extracorporeal substitutive treatment having congestive heart failure, chronic liver disease, diabetes and so forth. In these patients, however, long-term haemodialytic treatment may add further aggravation on their pre-existing pathological conditions. Oxidative stress and alterations in lipid metabolism are caused by haemodialysis mainly due to (1) bioincompatibility type of reactions such as production of reactive oxygen species by inflammatory cells due to complement-mediated or -independent pathways, and (2) the imbalance between oxidants and antioxidants due to the diffusive loss of hydrophilic vitamins such as ascorbic acid. The events related to the oxidant stress may sustain a state of chronic inflammation. Recent advances suggest that atherosclerosis and proliferation of the smooth muscle are initiated and sustained by inflammatory mechanisms. Therefore, attempts to counterbalance the prooxidant effect of haemodialysis and to reduce the chronic inflammatory state will be presented
Diffusive author(s), cohesive author: Analysis of S/N (1994)
No full textThis study indicates the ways in which various aspects of the author(s) are brought forth in Dumb type’s performance art, the S/N production. Previous research has suggested a non-hierarchical organization of Dumb type and the absence of a “privileged author” in Dumb type’s collaborative work, S/N. However, the results that I have investigated from member’s interviews on the creative process of S/N along with my analysis of the recorded images of S/N, indicate a different aspect of the author(s). First, S/N was created through, so to speak, the collective ideas of the members of Dumb type. Further, S/N has at least nine quotations from previous performances, installations, and printed writings, besides the work-in-progress technique. Explicating one of the “author functions” as given by Michel Foucault, each text has plural subjects of the author. However, it has been revealed from members’ interviews that Teiji Furuhashi had a decision-making role in selecting the members’ ideas within the performance. Since then, S/N has had plural subjects of creation; however, Furuhashi is one of the subjects of creation along with the “privileged author.” S/N has plural authors (diffusive authors) yet at the same time, it has a “privileged author,” Teiji Furuhashi (cohesive author)
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Disentangling higher trophic level interactions in the cabbage aphid food web using high-throughput DNA sequencing
No full textThe lack of understanding of complex food-web interactions has been a major gap in the history of biological control. In particular, a better understanding of the functioning of pest food-webs and how they vary between native and invaded geographical ranges is of prime interest for biological control research and associated integrated pest management. Technical limitations associated with the deciphering of complex food-webs can now be largely overcome by the use of high throughput DNA sequencing techniques such as Illumina MiSeq. We tested the efficiency of this next generation sequencing technology in a metabarcoding approach, to study aphid food-webs using the cabbage aphid as model. We compared the variations in structure and composition of aphid food-webs in the species' native range (United Kingdom, UK) and in an invaded range (New Zealand, NZ). We showed that Illumina MiSeq is a well suited technology to study complex aphid food-webs from aphid mummies. We found an unexpectedly high top down pressure in the NZ cabbage aphid food-web, which coupled to a large ratio of consumer species / prey species and a lack of potential inter-specific competition between primary parasitoids, could cause the NZ food-web to be more vulnerable than the UK one. This study also reports for the first time the occurrence of a new hyperparasitoid species in NZ, as well as new associations between hyperparasitoids parasitoids and the cabbage aphid in this country. We conclude that the complexity of aphid food-webs in agricultural systems could often be underestimated, particularly at higher trophic levels; and that the use of high throughput DNA sequencing tools, could largely help to overcome this impediment
Chemical ecology meets conservation biological control: identifying plant volatiles as predictors of floral resource suitability for an egg parasitoid of stink bugs
No full textConservation biological control aims to enhance natural enemy populations in crop habitats, e.g. by providing flowering plants as food resources. Suitable flower species must enhance the survival and fecundity of natural enemies but in addition they also need to be highly attractive and thus frequently visited. To date, few examples exist that have considered both criteria. In this study, we tested the effects of the flowering plants alyssum (Lobularia maritima), buckwheat (Fagopyrum esculentum), French marigold (Tagetes patula) and sweet basil (Ocimum basilicum) on the fecundity and olfactory attractiveness of the egg parasitoid Trissolcus basalis, an important biological control agent of the stink bug Nezara viridula. Our results showed that access to buckwheat and basil flowers increased the parasitoid offspring. However, in olfactometer experiments where T. basalis was allowed to choose between flowering and non-flowering plants, only buckwheat floral scent was attractive. Headspace analyses of the odour emitted by the four plant species revealed very distinct profiles with little overlap in compounds. Buckwheat floral scent was characterized by an unpleasant smell for the human nose due to the presence of short-chain carboxylic acids. Headspace extracts of buckwheat flowers and a blend of six buckwheat plant volatiles consisting of butanoic, 2-methylbutanoic, 3-methylbutanoic and pentanoic acids, (Z)-3-hexenyl acetate and α-farnesene were significantly attractive in olfactometer bioassays. Furthermore, electrophysiological experiments showed most of these compounds elicited significant responses in T. basalis antennae. Integrating chemo-ecological methods into conservation biological control allowed us to identify a potential resource plant and attractive compounds for field studies
Influence of domiciliary humidification on symptom burden and feeding tube use up to 2 years postradiation therapy for head and neck cancer: Trans-Tasman Radiation Oncology Group (TROG) 07.03 RadioHUM randomized phase 2 trial secondary analysis
No full textePoster Abstract #1126A.M.J. Macann, T. Fua, C.G. Milross, S. Porceddu, M.G. Penniment, C. Wratten, H. Krawitz, M.G. Poulsen, C.I. Tang, R.P. Morton, V. Thomson, M.L. Bell, M.T. King, C.L. Fraser-Browne, and H.U.P. Hocke
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