271 research outputs found

    Interior Landscape Plants for Indoor Air Pollution Abatement

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    In this study, the leaves, roots, soil, and associated microorganisms of plants have been evaluated as a possible means of reducing indoor air pollutants. Additionally, a novel approach of using plant systems for removing high concentrations of indoor air pollutants such as cigarette smoke, organic solvents, and possibly radon has been designed from this work. This air filter design combines plants with an activated carbon filter. The rationale for this design, which evolved from wastewater treatment studies, is based on moving large volumes of contaminated air through an activated carbon bed where smoke, organic chemicals, pathogenic microorganisms (if present), and possibly radon are absorbed by the carbon filter. Plant roots and their associated microorganisms then destroy the pathogenic viruses, bacteria, and the organic chemicals, eventually converting all of these air pollutants into new plant tissue. It is believed that the decayed radon products would be taken up the plant roots and retained in the plant tissue

    Frequency comb vernier spectroscopy in the near infrared

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    We perform femtosecond frequency comb vernier spectroscopy in the near infrared with a femtosecond Er doped fiber laser, a scanning high-finesse cavity and an InGaAs camera. By utilizing the properties of a frequency comb and a scanning high-finesse cavity such spectroscopy provides broad spectral bandwidth, high spectral resolution, and high detection sensitivity on a short time scale. We achieved an absorption sensitivity of ~8E-8 cm-1Hz-1/2 corresponding to a detection limit of ~70 ppbv for acetylene, with a resolution of ~1.1 GHz in single images taken in 0.5 seconds and covering a frequency range of ~5 THz. These measurements have broad applications for sensing other greenhouse gases in this fingerprint near IR region with a simple apparatus.Comment: 14 pages, 5 figure

    Thermal Frontal Polymerization with a Thermally Released Redox Catalyst

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    We studied thermal frontal polymerization using a redox systemin an attempt to lower the temperature of the frontally polymerizable system while increasing the front velocity so as to obtain a self-sustaining front in a thinner layer than without the redox components. A cobalt-containing polymer with a melting point of 63 C (Intelimer 6050X11) and cumene hydroperoxide were used with a triacrylate. The use of the Intelimer decreased the front velocity but allowed fronts to propagate in thinner layers and withmore filler while still having a pot life of days. Nonplanar modes of propagation occurred. Fronts propagated faster when 6-O-palmitoyl-L-ascorbic acid was used as a reductant. Interestingly, fronts were also faster with the reductant even without the Intelimer if kaolin clay was the filler; however, the pot life was significantly reduce

    Emergency Department Repair of Blunt Right Atrial Rupture Utilizing Cardiopulmonary Bypass

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    Blunt cardiac injury (BCI) with free wall rupture carries a high risk of pre-hospital death. Cardiopulmonary bypass (CPB) has been utilized as a bridge to repair of cardiac lesions in select patients. We present an interesting case of emergency department repair of right atrial rupture with cardiopulmonary bypass

    Mechanically transferred large-area Ga2_2O3_3 passivates graphene and suppresses interfacial phonon scattering

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    We demonstrate a large-area passivation layer for graphene by mechanical transfer of ultrathin amorphous Ga2_2O3_3 synthesized on liquid Ga metal. A comparison of temperature-dependent electrical measurements of millimetre-scale passivated and bare graphene on SiO2_2/Si indicate that the passivated graphene maintains its high field effect mobility desirable for applications. Surprisingly, the temperature-dependent resistivity is reduced in passivated graphene over a range of temperatures below 220 K, due to the interplay of screening of the surface optical phonon modes of the SiO2_2 by high-dielectric-constant Ga2_2O3_3, and the relatively high characteristic phonon frequencies of Ga2_2O3_3. Raman spectroscopy and electrical measurements indicate that Ga2_2O3_3 passivation also protects graphene from further processing such as plasma-enhanced atomic layer deposition of Al2_2O3_3.Comment: Journal article, 10 pages, 4 figure

    Changes in pain catastrophizing predict later changes in fibromyalgia clinical and experimental pain report: cross-lagged panel analyses of dispositional and situational catastrophizing

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    Introduction: Fibromyalgia (FM), characterized by wide-spread diffuse pain and sensory abnormalities, is associated with elevated indices of distress and pain-related catastrophizing compared to both pain-free samples and those with chronic pain conditions. Catastrophizing is a pervasive negative mental set, and is a strong predictor of negative pain-related outcomes such as clinical pain intensity, and physical disability. Situational catastrophizing, measured in the context of experimentally-induced pain, is strongly related to enhanced pain sensitivity, a core aspect of the pathophysiology of fibromyalgia. However, little is known regarding the temporal course of the association between catastrophizing and pain-related "outcomes". Most studies involve only static assessments of pain and catastrophizing at a single time point, which provides little insight into the direction of the observed associations. We sought to investigate the temporal relationships between catastrophizing and indices of both clinical pain (substudy 1) and experimentally-induced pain (substudy 2) in a larger randomized controlled longitudinal trial. Methods: Fifty-seven patients with FM completed catastrophizing, depression, and pain questionnaires as well as laboratory cold pressor pain testing at baseline, post-intervention and three month follow-up during a lifestyle physical activity study. Cross-lagged panel analyses were used to address these temporal relationships. Results: In substudy 1, analyses revealed that pre-to-post changes in dispositional catastrophizing ratings prospectively accounted for unique variance in subsequent post-to-follow-up changes in clinical pain ratings (p = 0.005), while pre-to-post changes in pain ratings did not account for unique variance in post-to-follow-up changes in catastrophizing ratings. An identical pattern was observed experimentally in substudy 2, with pre-to-post changes in situational catastrophizing ratings prospectively accounting for unique variance in subsequent post-to-follow-up changes in experimental pain ratings (p = 0.014), while pre-to-post changes in pain ratings did not account for unique variance in post-to-follow-up changes in catastrophizing ratings. Specifically, initial alterations in catastrophizing were associated with subsequent alterations in clinical and experimentally induced pain. Controlling for levels of depression did not affect the results. Conclusions: These findings provide empirical evidence that catastrophizing processes might precede and contribute to subsequent alterations in the pain experience for FM patients. Trial Registration clinicaltrials.gov: NCT00383084

    Warped Higgsless Models with IR--Brane Kinetic Terms

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    We examine a warped Higgsless SU(2)L×SU(2)R×U(1)B−LSU(2)_L\times SU(2)_R\times U(1)_{B-L} model in 5--dd with IR(TeV)--brane kinetic terms. It is shown that adding a brane term for the U(1)B−LU(1)_{B-L} gauge field does not affect the scale (∌2−3\sim 2-3 TeV) where perturbative unitarity in WL+WL−→WL+WL−W_L^+ W_L^- \to W_L^+ W_L^- is violated. This term could, however, enhance the agreement of the model with the precision electroweak data. In contrast, the inclusion of a kinetic term corresponding to the SU(2)DSU(2)_D custodial symmetry of the theory delays the unitarity violation in WL±W_L^\pm scattering to energy scales of ∌6−7\sim 6-7 TeV for a significant fraction of the parameter space. This is about a factor of 4 improvement compared to the corresponding scale of unitarity violation in the Standard Model without a Higgs. We also show that null searches for extra gauge bosons at the Tevatron and for contact interactions at LEP II place non-trivial bounds on the size of the IR-brane terms.Comment: 23 pages, 8 figure

    Networking Cities after Paris: Weighing the Ambition of Urban Climate Change Experimentation

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    Over the past few decades, cities have repeatedly demonstrated high levels of ambition with regard to climate action. Global environmental governance has been marked by a proliferation of policy actions taken by local governments around the world to demonstrate their potential to advance climate change mitigation and adaptation. Leading ‘by example’ and demonstrating the extent of action that it is possible to deliver, cities have aspired to raise the ambition of national and international climate governance and put action into practice via a growing number of ‘climate change experiments’ delivered on the ground. Yet accounts of the potential of cities in global environmental governance have often stopped short of a systematic valuation of the nature and impact of the networked dimension of this action. This article addresses this by assessing the nature, and challenges faced by, urban climate governance in the post-Paris era, focusing on the ‘experimentation’ undertaken in cities and the city networks shaping this type of governance. First, we unpack the concept of ‘urban climate change experimentation’, the ways in which it is networked, and the forces driving it. In the second and third parts of the article, we discuss two main pitfalls of networked urban experimentation in its current form, focusing on issues of scaling experiments and the nature of experimentation. We call for increased attention to ‘scaling up’ experiments beyond urban levels of governance, and to transformative experimentation with governance and politics by and in cities. Finally, we consider how these pitfalls allow us to weigh the potential of urban climate ambition, and consider the pathways available for supporting urban climate change experimentation

    Students’ perception of the position of ethics within an organisation

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    Abstract: This study examines the perceptions that senior business management students have towards the position of ethics within organisations in Johannesburg in relation to the availability of formal ethics programmes, ethical culture, ethical leadership and ethical value systems. Research Design & Methods: The study employed a quantitative survey design to collect data, using selfadministered questionnaires from the respondents. The data were then analysed using descriptive statistics. Reliability statistics were employed to test the reliability of each construct. Findings: The findings of this study showed that senior students have a positive perception of the ethical position of Conclusion: There is evidence of positive attitudes towards the ethical conduct of organisations. However, some evidence shows that some organisations consider results first and ethics later, despite the availability of ethical codes, value systems, and ethical leadership and culture
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