153 research outputs found
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Understanding the Role of Government and Buyers in Supplier Energy Efficiency Initiatives
In environmental management, companies must respond to myriad needs and pressures from
stakeholders such as buyers, regulators, communities and NGOs. While researchers recognize
that these stakeholder entities have different saliency and influences over a focal firm, the
influences from multiple stakeholders are often aggregated as a single factor, overlooking
differences among them. Stakeholders may have competing demands: A buyer may consider only
potential environment-cost trade-offs while the government balances the environment, increased
cost-competitive manufacturing and job creation. Such demands compete for the same resources
within the supplier’s organization, forcing suppliers to satisfice and compromise. This paper
qualitatively examines Chinese suppliers’ responses to requests to adopt energy efficiency
initiatives in their production plants by two of their most critical stakeholders: buyers and the
government. We identify three categories of energy efficiency (EE) initiatives implemented by
the suppliers and find that their implementations are contingent on their ownership
characteristics and value alignment with these two stakeholders. Further, we find that suppliers
interpret buyers’ motives regarding EE in the context of buyer-supplier relationships and
environmental positioning of the buyers’ products. These findings are articulated in a set of
propositions that are introduced based on our analysis of these case study data.KEYWORDS: Environmental decision-making, Supply management, Energy efficiency, China, Buyer-supplier relationship, Sustainability, case study, Stakeholder theory, Government influenceThis is an author's peer-reviewed final manuscript, as accepted by the publisher. The article is copyrighted by the Institute for Supply Management, Inc. and published by John Wiley & Sons Ltd. It can be found at: http://onlinelibrary.wiley.com/journal/10.1111/%28ISSN%291745-493X
Standing Balance and Spatiotemporal Aspects of Gait Are Impaired Upon Nocturnal Awakening in Healthy Late Middle-Aged and Older Adults
Study Objectives: Nocturnal awakenings may constitute a unique risk for falls among older adults. We describe differences in gait and balance between presleep and midsleep testing, and whether changes in the lighting environment during the midsleep testing further affect gait and balance.
Methods: Twenty-one healthy, late middle-aged and older (64.7 ± 8.0 y) adults participated in this repeated-measures design consisting of four overnight laboratory stays. Each night, participants completed baseline visual acuity, gait, and balance testing. After a 2-h sleep opportunity, they were awakened for 13 min into one of four lighting conditions: very dim white light (\u3c 0.5 lux); dim white light (∼28.0 lux); dim orange light (∼28.0 lux); and white room-level light (∼200 lux). During this awakening, participants completed the same sequence of testing as at baseline.
Results: Low-contrast visual acuity significantly decreased with decreasing illuminance conditions (F(3,45) = 98.26, p \u3c 0.001). Our a priori hypothesis was confirmed in that variation in stride velocity and center of pressure path length were significantly worse during the mid-sleep awakening compared to presleep baseline. Lighting conditions during the awakening, however, did not influence these parameters. In exploratory analyses, we found that over one-third of the tested gait and balance parameters were significantly worse at the midsleep awakening as compared to baseline (p \u3c 0.05), and nearly one-quarter had medium to large effect sizes (Cohen d ≥ 0.5; r ≥ 0.3).
Conclusions: Balance and gait are impaired during midsleep awakenings among healthy, late middle-aged and older adults. This impairment is not ameliorated by exposure to room lighting, when compared to dim lights
Tuple Space Explosion: A Denial-of-Service Attack Against a Software Packet Classifier
Efficient and highly available packet classification is fundamental for various security primitives. In this paper, we evaluate whether the de facto Tuple Space Search (TSS) packet classification algorithm used in popular software networking stacks such as the Open vSwitch is robust against low-rate denial-of-service attacks. We present the Tuple Space Explosion (TSE) attack that exploits the fundamental space/time complexity of the TSS algorithm.
TSE can degrade the switch performance to 12% of its full capacity with a very low packet rate (0.7 Mbps) when the target only has simple policies such as, "allow some, but drop others". Worse, an adversary with additional partial knowledge of these policies can virtually bring down the target with the same low attack rate. Interestingly, TSE does not generate any specific traffic patterns but only requires arbitrary headers and payloads which makes it particularly hard to detect.
Due to the fundamental complexity characteristics of TSS, unfortunately, there seems to be no complete mitigation to the problem. As a long-term solution, we suggest the use of other algorithms (e.g., HaRP) that are not vulnerable to the TSE attack. As a short-term countermeasure, we propose MFCGuard that carefully manages the tuple space and keeps packet classification fast
Illusory Stimuli Can Be Used to Identify Retinal Blind Spots
Background. Identification of visual field loss in people with retinal disease is not straightforward as people with eye disease are frequently unaware of substantial deficits in their visual field, as a consequence of perceptual completion ("filling-in'') of affected areas. Methodology. We attempted to induce a compelling visual illusion known as the induced twinkle after-effect (TwAE) in eight patients with retinal scotomas. Half of these patients experience filling-in of their scotomas such that they are unaware of the presence of their scotoma, and conventional campimetric techniques can not be used to identify their vision loss. The region of the TwAE was compared to microperimetry maps of the retinal lesion. Principal Findings. Six of our eight participants experienced the TwAE. This effect occurred in three of the four people who filled-in their scotoma. The boundary of the TwAE showed good agreement with the boundary of lesion, as determined by microperimetry. Conclusion. For the first time, we have determined vision loss by asking patients to report the presence of an illusory percept in blind areas, rather than the absence of a real stimulus. This illusory technique is quick, accurate and not subject to the effects of filling-in
Transcriptional repression of the human collagenase-1 (MMP-1) gene in MDA231 breast cancer cells by all-trans-retinoic acid requires distal regions of the promoter
In the present study, we investigated the mechanisms controlling constitutive transcription of collagenase-1 and its repression by all-trans-retinoic acid (RA) in the highly invasive metastatic and oestrogen-receptor-negative breast cancer cell line MDA231. A combination of in vivo and in vitro experiments that include DNAase I hypersensitivity assays, transient transfection of collagenase-1 promoter constructs, and electrophoretic mobility shift assays implicate several PEA3 sites, binding sites for Ets-related transcription factors, in the constitutive expression of the human collagenase-1 promoter. Transient transfection of promoter constructs linked to the luciferase reporter, along with gel retardation assays, revealed that repression of collagenase-1 transcription by RA is not dependent on the proximal AP-1 site, but, rather, requires sequences located in distal regions of the promoter. Transcriptional analyses and electrophoretic mobility shift assays suggest that the PEA3 site located at –3108 bp facilitates, at least in part, the transcriptional repression of the human collagenase-1 gene in MDA231 cells. We conclude that collagenase-1 repression in MDA231 cells occurs by a novel regulatory pathway that does not depend on the proximal AP-1 site at –73 bp, but does depend on distal regions in the collagenase-1 promoter. © 1999 Cancer Research Campaig
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