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Socio-technical transitions towards environmental sustainability through green ICT
We adopt the broad conceptualisation of Green Information Communication Technology (ICT) used by the Organisation for Economic Cooperation and Development (OECD), incorporating perspectives on Information Technology (IT) and Information Systems (IS) which has currency with both business practitioners and policy makers. The objective of our research is to develop a theory of the institutional mechanisms that underpin socio-technical transitions to environmental sustainability through the direct, indirect and systematic effects of Green ICT in and across organisational fields. We construct our theory by drawing on published research in several disciplines focusing on the organisational field of the ICT industry. We present a mechanism-based theoretical model that explains how institutional change in organisational fields can evoke appropriate socio-technical transitions and organisational responses to Green ICT. Systems researchers agree that Green ICT can help lower GHG emissions directly, through energy efficiencies and indirectly by enabling environmentally sustainable business processes. If this research is to be of theoretical or practical relevance it must recognize that government organizations and business enterprises may not adopt policies and strategies on Green ICT because it is rational or moral to do so rather, a web of social, and institutional mechanisms interact to produce the outcomes observed in practice
Environmental responsibilty and green IT: An institutional perspective
A recent Gartner Research report found that environmental concerns are increasingly exercising the minds of business and IT executives. This is reflected in the growing interest in the adoption of environmentally responsible approaches to the deployment, operation and use of IT. However, for the majority of firms, issues of cost reduction and energy efficiency appear to predominate. This paper argues that whether it is an interest in Green IT or in cost reduction, the concerns of business and IT managers are modulated by regulative, normative, and cultural-cognitive influences in the institutional environment. The study therefore applies institutional theory to develop a series of theoretical propositions which specify the effect that such influences have in shaping environmental responsibility in organisations. Important as such a theoretical contribution may be, there are, however, the pressing practical imperatives of formulating Green IT strategies, achieving energy efficiencies, and reducing carbon footprints—thus, the study also contributes to a practical understanding of the complex institutional influences at play in shaping such imperatives
Spectroscopic characterization and detection of Ethyl Mercaptan in Orion
New laboratory data of ethyl mercaptan, CHCHSH, in the millimeter
and submillimeter-wave domains (up to 880 GHz) provided very precise values of
the spectroscopic constants that allowed the detection of
-CHCHSH towards Orion KL. 77 unblended or slightly blended
lines plus no missing transitions in the range 80-280 GHz support this
identification. A detection of methyl mercaptan, CHSH, in the spectral
survey of Orion KL is reported as well. Our column density results indicate
that methyl mercaptan is 5 times more abundant than ethyl mercaptan in
the hot core of Orion KL.Comment: Accepted for publication in ApJL (30 January 2014)/ submitted (8
January 2014
Global MHD simulation of flux transfer events at the high-latitude magnetopause observed by the cluster spacecraft and the SuperDARN radar system
A global magnetohydrodynamic numerical simulation is used to study the large-scale structure and formation location of flux transfer events (FTEs) in synergy with in situ spacecraft and ground-based observations. During the main period of interest on the 14 February 2001 from 0930 to 1100 UT the Cluster spacecraft were approaching the Northern Hemisphere high-latitude magnetopause in the postnoon sector on an outbound trajectory. Throughout this period the magnetic field, electron, and ion sensors on board Cluster observed characteristic signatures of FTEs. A few minutes delayed to these observations the Super Dual Auroral Radar Network (SuperDARN) system indicated flow disturbances in the conjugate ionospheres. These “two-point” observations on the ground and in space were closely correlated and were caused by ongoing unsteady reconnection in the vicinity of the spacecraft. The three-dimensional structures and dynamics of the observed FTEs and the associated reconnection sites are studied by using the Block-Adaptive-Tree-Solarwind-Roe-Upwind-Scheme (BATS-R-US) MHD code in combination with a simple open flux tube motion model (Cooling). Using these two models the spatial and temporal evolution of the FTEs is estimated. The models fill the gaps left by measurements and allow a “point-to-point” mapping between the instruments in order to investigate the global structure of the phenomenon. The modeled results presented are in good correlation with previous theoretical and observational studies addressing individual features of FTEs
Neural and physiological data from participants listening to affective music
Music provides a means of communicating affective meaning. However, the neurological mechanisms by which music induces affect are not fully understood. Our project sought to investigate this through a series of experiments into how humans react to affective musical stimuli and how physiological and neurological signals recorded from those participants change in accordance with self-reported changes in affect. In this paper, the datasets recorded over the course of this project are presented, including details of the musical stimuli, participant reports of their felt changes in affective states as they listened to the music, and concomitant recordings of physiological and neurological activity. We also include non-identifying meta data on our participant populations for purposes of further exploratory analysis. This data provides a large and valuable novel resource for researchers investigating emotion, music, and how they affect our neural and physiological activity
Evaluation of a spring-powered captive bolt gun for killing kangaroo pouch young
Context: During commercial harvesting or non-commercial kangaroo culling programs, dependent young of shot females are required to be euthanased to prevent suffering and because they would be unlikely to survive. However, the current method for killing pouch young, namely a single, forceful blow to the base of the skull, is applied inconsistently by operators and perceived by the public to be inhumane.
Aims: To determine whether an alternative method for killing pouch young, namely a spring-operated captive bolt gun, is effective at causing insensibility in kangaroo pouch young.
Methods: Trials of spring-operated captive bolt guns were conducted first on the heads of 15 dead kangaroo young and then on 21 live pouch young during commercial harvesting. We assessed the effectiveness at causing insensibility in live animals and damage caused to specific brain areas. We also measured depth of bolt penetration and skull thickness. Performance characteristics (e.g. bolt velocity) of two types of spring-operated guns were also measured and compared with cartridge-powered devices.
Key results: When tested on the heads of dead animals, the spring-operated captive bolt gun consistently produced a large entrance cavity and a well defined wound tract, which extended into the cerebrum, almost extending the full thickness of the brain, including the brainstem. When tested on live pouch young, the captive bolt gun caused immediate insensibility in only 13 of 21 animals. This 62% success rate is significantly below the 95% minimum acceptable threshold for captive bolt devices in domestic animal abattoirs. Failure to stun was related to bolt placement, but other factors such as bolt velocity, bolt diameter and skull properties such as thickness and hardness might have also contributed. Spring-operated captive bolt guns delivered 20 times less kinetic energy than did cartridge-powered devices.
Conclusions: Spring-operated captive bolt guns cannot be recommended as an acceptable or humane method for stunning or killing kangaroo pouch young.
Implications: Captive bolt guns have potential as a practical alternative to blunt head trauma for effective euthanasia and reducing animal (and observer) distress. However, operators must continue to use the existing prescribed killing methods until cartridge-powered captive bolt guns have been trialled as an alternative bolt propelling method.
Additional keywords: animal welfare, blunt trauma, culling, euthanasia, humaneness, kangaroo harvesting
The first patient treatment of computed tomography ventilation functional image-guided radiotherapy for lung cancer.
BACKGROUND AND PURPOSE: Radiotherapy that selectively avoids irradiating highly-functional lung regions may reduce pulmonary toxicity. We report on the first clinical implementation and patient treatment of lung functional image-guided radiotherapy using an emerging technology, computed tomography (CT) ventilation imaging. MATERIAL AND METHODS: A protocol was developed to investigate the safety and feasibility of CT ventilation functional image-guided radiotherapy. CT ventilation imaging is based on (1) deformable image registration of four-dimensional (4D) CT images, and (2) quantitative image analysis for regional volume change, a surrogate for ventilation. CT ventilation functional image-guided radiotherapy plans were designed to minimize specific lung dose-function metrics, including functional V20 (fV20), while maintaining target coverage and meeting standard constraints to other critical organs. RESULTS: CT ventilation functional image-guided treatment planning reduced the lung fV20 by 5% compared to an anatomic image-guided plan for an enrolled patient with stage IIIB non-small cell lung cancer. Although the doses to several other critical organs increased, the necessary constraints were all met. CONCLUSIONS: An emerging technology, CT ventilation imaging has been translated into the clinic and used in functional image-guided radiotherapy for the first time. This milestone represents an important first step toward hypothetically reduced pulmonary toxicity in lung cancer radiotherapy
The impact of resource dependence of the mechanisms of life on the spatial population dynamics of an in silico microbial community
Biodiversity has a critical impact on ecosystem functionality and stability, and thus the current biodiversity crisis has motivated many studies of the mechanisms that sustain biodiversity, a notable example being non-transitive or cyclic competition. We therefore extend existing microscopic models of communities with cyclic competition by incorporating resource dependence in demographic processes, characteristics of natural systems often oversimplified or overlooked by modellers. The spatially explicit nature of our individual-based model of three interacting species results in the formation of stable spatial structures, which have significant effects on community functioning, in agreement with experimental observations of pattern formation in microbial communities. Published by AIP Publishing
Crater Morphometry and Scaling in Coarse, Rubble-Like Targets: Insights from Impact Experiments
Spacecraft images reveal that the asteroids Itokawa, Ryugu, and Bennu are covered with coarse, boulder-rich material [13]. Impactors that collide with these bodies encounter a target with extreme physical heterogeneity. Other bodies can also possess significant physical heterogeneity (e.g., megaregolith, layering, etc.). Such heterogeneities establish free surfaces and impedance contrasts that can affect shock propagation and attenuation. Therefore, such heterogeneities may also affect crater formation and excavation [4], melt generation [57] and crater scaling [4]. As described by [8,9], the extent to which target heterogeneity affects crater formation likely depends on how the length scale, d, of the heterogeneity (e.g., boulder size on a rubble-pile asteroid) compares to the width of the shock, w, generated by impact. Here we further test this hypothesis using impact experiments across a broad range of impact velocities and target grain sizes to systematically vary the ratio between the width of the shock and the diameter of target grains
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