46 research outputs found

    The optical flare

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    Optical observationd now present considerable information on the flare process. It is always associated with filaments and with simplification of existing magnetic connections, and it arises from the emergence and expansion of new flux. The optical flare divides into impulsive phase, with multiple flashes along the neutral line, and thermal phase, with two-ribbon expansion. The former bears some resemblance to tearing mode phenomena. The appearance of loops in emission requires very high densities in those phenomena. The ratios of the hydrogen lines, the excitation of HeII 4686, and the relation of vertical to horizontal structure all remain to be explained

    Radiotherapy for Soft Tissue Sarcomas after Isolated Limb Perfusion and Surgical Resection: Essential for Local Control in All Patients?

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    Background: Standard treatment for localized soft tissue sarcoma (STS) is resection plus adjuvant radiotherapy (RTx). In approximately 10% of cases, resection would cause severe loss of function or even require amputation because of the extent of disease. Isolated limb perfusion (ILP) with tumor necrosis factor alpha (TNF-α) and melphalan can achieve regression of the tumor, facilitating limb-saving resection. RTx improves local control but may lead to increased morbidity. Methods: In our database of over 500 ILPs, 122 patients with unifocal STS were treated by ILP followed by limb-sparing surgery. All included patients were candidates for amputation. Results: Surgery resulted in 69 R0 resections (57%), and in 53 specimens (43%) resection margins contained microscopic evidence of tumor (R1). Histopathological examination revealed >50% ILP-induced tumor necrosis in 59 cases (48%). RTx was administered in 73 patients (60%). Local recurrence rate was 21% after median follow-up of 31 months (2-182 months). Recurrence was significantly less in patients with >50% ILP-induced necrosis versus ≤50% necrosis (7% vs. 33%, P = 0.001). A similar significant correlation was observed for R0 versus R1 resections (15% vs. 28%, P = 0.04). In 36 patients with R0 resection and >50% necrosis, of whom 21 were spared RTx, no recurrences were observed during follow-up. Conclusions: In patients with locally advanced primary STS, treated with ILP followed by R0 resection, and with >50% ILP-induced necrosis in the resected specimen, RTx is of no further benefit

    Isolated Limb Perfusion and External Beam Radiotherapy for Soft Tissue Sarcomas of the Extremity: Long-Term Effects on Normal Tissue According to the LENT-SOMA Scoring System

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    BACKGROUND: With the combined treatment procedure of isolated limb perfusion (ILP), delayed surgical resection and external beam radiotherapy (EBRT) for locally advanced soft tissue sarcomas (STS) of the extremities, limb salvage rates of more than 80% can be achieved. However, long-term damage to the healthy surrounding tissue cannot be prevented. We studied the late effects on the normal tissue using the LENT-SOMA scoring system. PATIENTS AND METHODS: A total of 32 patients-median age 47 (range 14-71) years-were treated for a locally advanced STS with ILP, surgical resection and often adjuvant 60-70 Gy EBRT. After a median follow-up of 88 (range 17-159) months, the patients were scored, using the LENT-SOMA scales, for the following late tissue damage: muscle/soft tissue, peripheral nerves, skin/subcutaneous tissue and vessels. RESULTS: According to the individual SOM parameters of the LENT-SOMA scales, 20 patients (63%) scored grade-3 toxicity on one or more separate items, reflecting severe symptoms with a negative impact on daily activities. Of these patients, 3 (9%) even scored grade-4 toxicity on some of the parameters, denoting irreversible functional damage necessitating major therapeutic intervention. CONCLUSIONS: In evaluating long-term morbidity after a combined treatment procedure for STS of the extremity, using modified LENT-SOMA scores, two-thirds of patients were found to have experienced serious late toxic effects

    Australian chiropractic sports medicine: half way there or living on a prayer?

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    Sports chiropractic within Australia has a chequered historical background of unorthodox individualistic displays of egocentric treatment approaches that emphasise specific technique preference and individual prowess rather than standardised evidence based management. This situation has changed in recent years with the acceptance of many within sports chiropractic to operate under an evidence informed banner and to embrace a research culture. Despite recent developments within the sports chiropractic movement, the profession is still plagued by a minority of practitioners continuing to espouse certain marginal and outlandish technique systems that beleaguer the mainstream core of sports chiropractic as a cohesive and homogeneous group. Modern chiropractic management is frequently multimodal in nature and incorporates components of passive and active care. Such management typically incorporates spinal and peripheral manipulation, mobilisation, soft tissue techniques, rehabilitation and therapeutic exercises. Externally, sports chiropractic has faced hurdles too, with a lack of recognition and acceptance by organized and orthodox sports medical groups. Whilst some arguments against the inclusion of chiropractic may be legitimate due to its historical baggage, much of the argument appears to be anti-competitive, insecure and driven by a closed-shop mentality.sequently, chiropractic as a profession still remains a pariah to the organised sports medicine world. Add to this an uncertain continuing education system, a lack of protection for the title 'sports chiropractor', a lack of a recognized specialist status and a lack of support from traditional chiropractic, the challenges for the growth and acceptance of the sports chiropractor are considerable. This article outlines the historical and current challenges, both internal and external, faced by sports chiropractic within Australia and proposes positive changes that will assist in recognition and inclusion of sports chiropractic in both chiropractic and multi-disciplinary sports medicine alike

    Pro-autophagic signal induction by bacterial pore-forming toxins

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    Pore-forming toxins (PFT) comprise a large, structurally heterogeneous group of bacterial protein toxins. Nucleated target cells mount complex responses which allow them to survive moderate membrane damage by PFT. Autophagy has recently been implicated in responses to various PFT, but how this process is triggered is not known, and the significance of the phenomenon is not understood. Here, we show that S. aureus α-toxin, Vibrio cholerae cytolysin, streptolysin O and E. coli haemolysin activate two pathways leading to autophagy. The first pathway is triggered via AMP-activated protein kinase (AMPK). AMPK is a major energy sensor which induces autophagy by inhibiting the target of rapamycin complex 1 (TORC1) in response to a drop of the cellular ATP/AMP-ratio, as is also observed in response to membrane perforation. The second pathway is activated by the conserved eIF2α-kinase GCN2, which causes global translational arrest and promotes autophagy in response to starvation. The latter could be accounted for by impaired amino acid transport into target cells. Notably, PKR, an eIF2α-kinase which has been implicated in autophagy induction during viral infection, was also activated upon membrane perforation, and evidence was obtained that phosphorylation of eIF2α is required for the accumulation of autophagosomes in α-toxin-treated cells. Treatment with 3-methyl-adenine inhibited autophagy and disrupted the ability of cells to recover from sublethal attack by S. aureus α-toxin. We propose that PFT induce pro-autophagic signals through membrane perforation–dependent nutrient and energy depletion, and that an important function of autophagy in this context is to maintain metabolic homoeostasis

    The Optical Flare

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    Optical observations now present considerable information on the flare process. It is always associated with filaments and with simplification of existing magnetic connections, and it arises from the emergence and expansion of new flux. The optical flare divides into impulsive phase, with multiple flashes along the neutral line, and thermal phase, with two-ribbon expansion. The former bears some resemblance to tearing mode phenomena. The appearance of loops in emission requires very high densities in those phenomena. The ratios of the hydrogen lines, the excitation of HeII 4686, and the relation of vertical to horizontal structure all remain to be explained

    Designing for trust: A case of value-sensitive design

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    In this paper, we consider the meaning, roles, and uses of trust in the economic and public domain, focusing on the task of designing systems for trust in information technology. We analyze this task by means of a survey of what trust means in the economic and public domain, using the model proposed by Lewicki and Bunker, and using the emerging paradigm of value-sensitive design. We explore the difficulties developers face when designing information technology for trust and show how our analysis in conjunction with existing engineering design methods provides means to address these difficulties. Our main case concerns a concrete problem in the economic domain, namely the transfer of control from customs agencies to companies. Control of individual items is increasingly untenable and is replaced by control on the level of companies aimed at determining whether companies can be trusted to be in control of their business and to be in compliance with applicable regulations. This transfer sets the task for companies to establish this trust by means of information technology systems. We argue that this trust can be achieved by taking into account philosophical analyses of trust and by including both parties in the trust relationship as clients for whom the information technology systems are to be designed.Values and TechnologyTechnology, Policy and Managemen

    Facilitating peripheral interaction: design and evaluation of peripheral interaction for a gesture-based lighting control with multimodal feedback

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    © 2015, The Author(s). Most interactions with today’s interfaces require a person’s full and focused attention. To alleviate the potential clutter of focal information, we investigated how interactions could be designed to take place in the background or periphery of attention. This paper explores whether gestural, multimodal interaction styles of an interactive light system allow for this. A study compared the performance of interactions with the light system in two conditions: the central condition in which participants interacted only with the light system, and the peripheral condition in which they interacted with the system while performing a high-attentional task simultaneously. Our study furthermore compared different feedback styles (visual, auditory, haptic, and a combination). Results indicated that especially for the combination feedback style, the interaction could take place without participants’ full visual attention, and performance did not significantly decrease in the peripheral condition. This seems to indicate that these interactions at least partly took place in their periphery of attention and that the multimodal feedback style aided this process

    Core Values and Value Conflicts in Cybersecurity: Beyond Privacy Versus Security

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    This chapter analyses some of the main values, and values conflicts, in relation to cybersecurity by distinguishing four important value clusters that should be considered when deciding on cybersecurity measures. These clusters are security, privacy, fairness and accountability. Each cluster consists of a range of further values, which can be viewed as articulating specific moral reasons relevant when devising cybersecurity measures. In addition to the four value clusters, domain-specific values that are served by computer systems, such as health, are important. Following a detailed discussion of the four relevant value clusters, potential value conflicts and value tensions are considered. The relationships of five pairs of values (privacy-security, privacy-fairness, privacy-accountability, security-accountability and security-fairness) are analysed in terms of whether they are largely supportive or conflicting. In addition, possible methods for addressing these potential value conflicts are discussed. It is concluded that values, and value conflicts, in cybersecurity should be considered in context, also taking into account the specific computer systems at play, to enable the use of nuanced and fine-grained methods for addressing the relevant value conflicts.Values Technology and Innovatio
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