1,326 research outputs found
Standardizing sustainability : certifying Tanzanian biofuel smallholders in a global supply chain
Standards and certifications, as ‘scientific’ instruments of public and private governance, have recently emerged as ways to deal with growing concerns about the triple P sustainability of global supply chains for renewable energy. Focussing on a chain for sourcing ‘sustainable’ biokerosene for use by a major European airline, this article studies the practice of a pilot certification project aimed at thousands of Tanzanian smallholders who cultivate Jatropha oilseeds (one of the few known feedstocks suitable for biokerosene production). In particular, we study the tense interactions and encounters between a ‘universal’ biofuel sustainability standard, designed in an ostentatiously participatory process in the Netherlands, and the socio-ecological realities of the smallholders in Tanzania. As a result of these encounters, many provisions in the standard and certification protocols were found to constitute cases of ‘excess governance’, which made little or no sense in the Tanzanian smallholder context. At the same time, the standard was found to exhibit instances of ‘deficient governance’ leaving several critical issues outside its purview. Most importantly however were the cases where the provisions in the standard were deemed legitimate by the project’s implementers. Operationalization of these provisions in the smallholders’ surroundings however relied on major translation efforts involving significant brainstorming in Tanzania, conducting remedial research for problem-solving, and perhaps most importantly, significant improvisation in the field. As a result of this operationalization, many of the standard’s provisions had to undergo modifications that were initially resisted by the standard’s designers. These modifications may have resulted in a standard that is more aligned with the local realities encountered in a particular region of Tanzania. But other frictions, similar and different from the ones discussed in this article, are bound to crop up as this ‘adjusted’ standard moves to newer locales and encounters diverse social realities. In concluding, we call for regional or niche standardization strategies, rejecting the idea of universal standards that can be applied globally. A niche standardization strategy, while serving the intended purpose of the standards (in terms of ‘social’ and environmental sustainability), should facilitate the poorest farmers from reaping the benefits of the sustainability of their existing practices, a sustainability they cannot afford to prove ‘scientifically’
Huge decreases in the risk of breast cancer relapse over the last three decades
Introduction
The aim of this study was to evaluate local and systemic breast cancer control by comparing the risk of relapse in breast cancer patients in 2003–2004 with that in 1972–1979 and in 1980–1986.
Methods
About 8,570 women diagnosed with invasive breast cancer in 2003–2004 were selected from the population-based Netherlands Cancer Registry and compared with 133 patients treated in 1972–1979 and 174 in 1980–1986. Five-year risk of relapse was calculated by the Kaplan–Meier method. Cox-proportional hazard models were applied to adjust for tumour size, nodal status and age at diagnosis.
Results
Patients diagnosed in 2003–2004 had smaller tumours and a less advanced nodal stage than patients diagnosed in 1972–1986. In 1972–1979, 1980–1986 and 2003–2004, treatment included mastectomy in 94%, 72% and 47%; postmastectomy radiotherapy in 75%, 70% and 30%; chemotherapy in 9%, 14% and 37% and hormonal therapy in 3%, 3% and 42% of patients, respectively. Five-year risk of locoregional and distant recurrence decreased from 37% and 34% to 15%, respectively. The 5-year risk of second primary breast cancer did not differ and was 1%, 4% and 2%, respectively. The improved relapse-free survival in patients diagnosed in 2003–2004 as compared with 1972–1979 hardly changed after adjustment (HR = 0.38, 95% CI = 0.28–0.52).
Conclusion
Over the last decades, local breast cancer therapies have become less rigorous, whereas systemic therapy use has increased. Simultaneously, the risk of breast cancer relapse has tremendously decreased. Future novel therapies may lead to such small additional decreases in relapse rates, while the long-term side effects in breast cancer survivors will increas
Depletion-Induced Chiral Chain Formation of Magnetic Spheres
Experimental evidence is presented for the spontaneous formation of chiral configurations in bulk dispersions of magnetized colloids that interact by a combination of anisotropic dipolar interactions and isotropic depletion attractions. The colloids are superparamagnetic silica spheres, magnetized and aligned by a carefully tuned uniform external magnetic field; isotropic attractions are induced by using poly(ethylene oxide) polymers as depleting agents. At specific polymer concentrations, sphere chains wind around each other to form helical structures–of the type that previously have only been observed in simulations on small sets of unconfined dipolar spheres with additional isotropic interactions
Microbial catabolic activities are naturally selected by metabolic energy harvest rate
The fundamental trade-off between yield and rate of energy harvest per unit of substrate has been largely discussed as a main characteristic for microbial established cooperation or competition. In this study, this point is addressed by developing a generalized model that simulates competition between existing and not experimentally reported microbial catabolic activities defined only based on well-known biochemical pathways. No specific microbial physiological adaptations are considered, growth yield is calculated coupled to catabolism energetics and a common maximum biomass-specific catabolism rate (expressed as electron transfer rate) is assumed for all microbial groups. Under this approach, successful microbial metabolisms are predicted in line with experimental observations under the hypothesis of maximum energy harvest rate. Two microbial ecosystems, typically found in wastewater treatment plants, are simulated, namely: (i) the anaerobic fermentation of glucose and (ii) the oxidation and reduction of nitrogen under aerobic autotrophic (nitrification) and anoxic heterotrophic and autotrophic (denitrification) conditions. The experimentally observed cross feeding in glucose fermentation, through multiple intermediate fermentation pathways, towards ultimately methane and carbon dioxide is predicted. Analogously, two-stage nitrification (by ammonium and nitrite oxidizers) is predicted as prevailing over nitrification in one stage. Conversely, denitrification is predicted in one stage (by denitrifiers) as well as anammox (anaerobic ammonium oxidation). The model results suggest that these observations are a direct consequence of the different energy yields per electron transferred at the different steps of the pathways. Overall, our results theoretically support the hypothesis that successful microbial catabolic activities are selected by an overall maximum energy harvest rate
The impact of human-robot synchronization on anthropomorphization
To elucidate the working mechanism behind anthropomorphism, this study investigated whether human participants would anthropomorphize a robot more if they move synchronously versus non-synchronously with it, and whether this is affected by which of the two initiates the movements. We tested two competing hypotheses. The feature-overlap hypothesis predicts that moving in synchrony would increase perceived self-other feature overlap, which in turn might spread activation to codes of features related to humans—which should increase anthropomorphization. In contrast, the autonomy hypothesis predicts that unpredictability increases anthropomorphization, and thus that whenever the robot initiates movements, or when the human initiates movements to which the robot moves non-synchronously, there is an increased perception of the robot as a more human-like, intentionally acting creature, which in turn should increase anthropomorphization. We performed a study with synchrony as within-subjects factor, and initiator (robot or human) as between-subjects factor. To study the impact of synchrony on self-other overlap and perception of human likeness, participants completed two tasks that served as implicit measures of state anthropomorphization, and two questionnaires that served as explicit measures of state anthropomorphization toward the robot. The two implicit measures were the joint Simon task and one-shot Dictator Game. Additionally, participants filled in a trait anthropomorphization questionnaire, to enable correction for baseline tendencies to anthropomorphize. The synchrony manipulation did not affect the joint Simon effect, although there was an effect on average reaction time (RT), where in the group in which the robot initiated the movement, RTs were slower when the human and robot moved non-synchronously. The Dictator Game offer and the state anthropomorphization questionnaires were not affected by the synchrony manipulation. There was, however, a positive correlation between current anthropomorphization of the robot and amount of money offered to it. Given that most measures were not systematically affected by our manipulation, it appears that either our design was suboptimal, or that synchronization does not affect the anthropomorphization of a robot.Action Contro
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