172 resultados para Anti-vibration gloves
Resumo:
Human activity-induced vibrations in slender structural sys tems become apparent in many different excitation modes and consequent action effects that cause discomfort to occupants, crowd panic and damage to public infrastructure. Resulting loss of public confidence in safety of structures, economic losses, cost of retrofit and repairs can be significant. Advanced computational and visualisation techniques enable engineers and architects to evolve bold and innovative structural forms, very often without precedence. New composite and hybrid materials that are making their presence in structural systems lack historical evidence of satisfactory performance over anticipated design life. These structural systems are susceptible to multi-modal and coupled excitation that are very complex and have inadequate design guidance in the present codes and good practice guides. Many incidents of amplified resonant response have been reported in buildings, footbridges, stadia a nd other crowded structures with adverse consequences. As a result, attenuation of human-induced vibration of innovative and slender structural systems very ofte n requires special studies during the design process. Dynamic activities possess variable characteristics and thereby induce complex responses in structures that are sensitive to parametric variations. Rigorous analytical techniques are available for investigation of such complex actions and responses to produce acceptable performance in structural systems. This paper presents an overview and a critique of existing code provisions for human-induced vibration followed by studies on the performance of three contrasting structural systems that exhibit complex vibration. The dynamic responses of these systems under human-induced vibrations have been carried out using experimentally validated computer simulation techniques. The outcomes of these studies will have engineering applications for safe and sustainable structures and a basis for developing design guidance.
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Across Australia in 1968, students demonstrating against the Vietnam War engaged in confrontational behaviour. The metropolitan daily newspapers,the most important source of news for most people, enthusiastically reported the scenes. The demonstrations were exciting. Sensational headlines and photographs captured the interest of readers and influenced their opinions. But radical opposition to government policies at the time was not limited to university students opposing the Vietnam War. Teachers had become increasingly critical of conditions in schools, with Victorian secondary school teachers having stopped work on a number of occasions since 1965. In October 1968, both primary and secondary school teachers in New South Wales participated in eastern Australia’s first state-wide teachers’ strike. As Sydney’s Sun commented on 1 October 1968, “The teachers’ strike threw the ... education system into chaos ... A huge proportion of the State’s 2764 schools were silent and empty.” Similarities with the anti-war demonstrations were obvious. Although not as confrontational, the New South Wales teachers’ strike was a publicity-seeking action. This examination of the teachers’ more restrained, but more effective, approach to challenging government policies provides a new voice and vision to our understandings of the diverse nature of radicalism in Australia in the 1960s.
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The mechanical vibration properties of single actin filaments from 50 to 288 nm are investigated by the molecular dynamics simulation in this study. The natural frequencies obtained from the molecular simulations agree with those obtained from the analytical solution of the equivalent Euler–Bernoulli beam model. Through the convergence study of the mechanical properties with respect to the filament length, it was found that the Euler–Bernoulli beam model can only be reliably used when the single actin filament is of the order of hundreds of nanometre scale. This molecular investigation not only provides the evidence for the use of the continuum beam model in characterising the mechanical properties of single actin filaments, but also clarifies the criteria for the effective use of the Euler–Bernoulli beam model.
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Since 11 September 2001, Muslim minorities have experienced intensive "othering" in “Western” countries, above all in those US-led anglophone nations which invaded Afghanistan and Iraq to prosecute their "war on terror". This paper examines the cases of Britain and Australia, where whole communities of Muslims have been criminalised as "evil" and a "fifth column" enemy within by media, politicians, the security services and the criminal justice system. Although constituted by disparate ethnic groups, the targeted communities in each of these nations have experienced similar treatment in the State's anti-terrorist measures, as well as ideological responses and everyday racism, making comparable the two cases.
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Columns and walls in buildings are subjected to a number of load increments during the construction and service stages. The combination of these load increments and poor quality construction can cause defects in these structural components. In addition, defects can also occur due to accidental or deliberate actions by users of the building during construction and service stages. Such defects should be detected early so that remedial measures can be taken to improve life time serviceability and performance of the building. This paper uses micro and macro model upgrading methods during construction and service stages of a building based on the mass and stiffness changes to develop a comprehensive procedure for locating and detecting defects in columns and walls of buildings. Capabilities of the procedure are illustrated through examples.
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We hypothesised that a potentially disease-modifying osteoarthritis (OA) drug such as hyaluronic acid (HA) given in combination with anti-inflammatory signalling agents such as mitogen-activated protein kinase kinase–extracellular signal-regulated kinase (MEK-ERK) signalling inhibitor (U0126) could result in additive or synergistic effects on preventing the degeneration of articular cartilage. Chondrocyte differentiation and hypertrophy were evaluated using human OA primary cells treated with either HA or U0126, or the combination of HA + U0126. Cartilage degeneration in menisectomy (MSX) induced rat OA model was investigated by intra-articular delivery of either HA or U0126, or the combination of HA + U0126. Histology, immunostaining, RT-qPCR, Western blotting and zymography were performed to assess the expression of cartilage matrix proteins and hypertrophic markers. Phosphorylated ERK (pERK)1/2-positive chondrocytes were significantly higher in OA samples compared with those in healthy control suggesting the pathological role of that pathway in OA. It was noted that HA + U0126 significantly reduced the levels of pERK, chondrocyte hypertrophic markers (COL10 and RUNX2) and degenerative markers (ADAMTs5 and MMP-13), however, increased the levels of chondrogenic markers (COL2) compared to untreated or the application of HA or U0126 alone. In agreement with the results in vitro, intra-articular delivery of HA + U0126 showed significant therapeutic improvement of cartilage in rat MSX OA model compared with untreated or the application of HA or U0126 alone. Our study suggests that the combination of HA and MEK-ERK inhibition has a synergistic effect on preventing cartilage degeneration.
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Abstract: This study explores the contradictions and ambivalences experienced by a working artist at a time when her age, her gender, and broader cultural shifts are all potential obstacles or liabilities to creative flourishing. It is the product of practice-led research into the creative process from the perspective of the female "late bloomer". In this phrase, I have in mind the mature-aged woman who is, in mid-life, suddenly seized with inspiration and fired with creative energy. At its heart is the question: If an Elizabeth Jolley were in our midst today, would we hear from her? The result is a full-length libretto and accompanying exegetical binoculars in the form of a Preface and an Afterword. The creative work, Things That Fall Over (TTFO) is conceived in two parts: a libretto and oratorio for performance. It begins as a play, but over three acts and into a coda, the work becomes something entirely other - an (anti-) musical. The work grew from a personal interest in the nexus between women, ageing and creative practice, via investigation into the oeuvre of two Australian artists, Elizabeth Jolley, author, first published at age 53, and Rosalie Gascoigne, sculptor, first exhibited at 58. A second strand of the research grew from a fascination for the stage musical, especially in its more alternative modes as in the hands of Stephen Sondheim, or in more provocative manifestations as witnessed in recent Tony Award winners Avenue Q and The Book of Mormon. Contextually, this research is conducted at a time when anecdotal evidence suggests that women’s work in the performing arts and in literature is being pushed to the margins after a late twentieth century Golden Age on page and stage. Using hybrid practice-led methodologies - bricolage, log-keeping - and working within queer and feminist paradigms, this study seeks to counter that push with a new work that is all-female, part-pantomime, part monstrous allegory. In illuminating the creative process of a mature-aged playwright it concludes that hybrid and interstitial forms still offer an inclusive and democratic space in which voices that may otherwise be muted will continue to be heard.
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The backlash against gender-sensitive responses to women's victimization, offending, and imprisonment is inseparable from contemporary reaction against feminism and other progressive movements. The backlash against the American Violence Against Women Act (VAWA) provides a prime example of this resistance. Despite widespread support for VAWA and other policies designed to address violence against women, some constituencies object to their existence. The author investigates fathers' rights rhetoric on VAWA as an example of antifeminist backlash.
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Dual-mode vibration of nanowires has been reported experimentally through actuation of the nanowire at its resonance frequency, which is expected to open up a variety of new modalities for the NEMS that could operate in the nonlinear regime. In the present work, we utilize large scale molecular dynamics simulations to investigate the dual-mode vibration of <110> Ag nanowires with triangular, rhombic and truncated rhombic cross-sections. By incorporating the generalized Young-Laplace equation into Euler-Bernoulli beam theory, the influence of surface effects on the dual-mode vibration is studied. Due to the different lattice spacing in principal axes of inertia of the {110} atomic layers, the NW is also modeled as a discrete system to reveal the influence from such specific atomic arrangement. It is found that the <110> Ag NW will under a dual-mode vibration if the actuation direction is deviated from the two principal axes of inertia. The predictions of the two first mode natural frequencies by the classical beam model appear underestimated comparing with the MD results, which are found to be enhanced by the discrete model. Particularly, the predictions by the beam theory with the contribution of surface effects are uniformly larger than the classical beam model, which exhibit better agreement with MD results for larger cross-sectional size. However, for ultrathin NWs, current consideration of surface effects is still experiencing certain inaccuracy. In all, for all different cross-sections, the inclusion of surface effects is found to reduce the difference between the two first mode natural frequencies. This trend is observed consistent with MD results. This study provides a first comprehensive investigation on the dual-mode vibration of <110> oriented Ag NWs, which is supposed to benefit the applications of NWs that acting as a resonating beam.
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Speeding represents a major contributor to road trauma, increasing crash frequency and severity. Antispeeding campaigns represent a key strategy aimed at discouraging individuals from speeding. This paper investigated salient beliefs underpinning male and female drivers’ travel speed behaviour, with the view to use such insight to, ultimately, inform the content of targeted anti-speeding messages. A survey of N = 751 (579 males, 16-79 years) drivers assessed what they regarded as speeding in 60km/hr and 100km/hr zones and their beliefs about how they would respond to receiving a speeding infringement. Participants responded to scales which extended up to 20km/hr above each respective speed limit, the lowest speed that they considered was speeding and the speed at which they would be willing to drive and still feel in control. For analyses, to enable greater scrutiny of potential gender differences regarding the speeds identified, participants’ responses to these items were categorised into 5km/hr increments and chi-square analyses conducted. For their responses to (beliefs about) the possibility of being caught speeding, drivers were asked how applicable various beliefs were to them (e.g., feeling unlucky). These beliefs were analysed via MANOVA. The results revealed that there was considerable variability in the speeds identified, thus supporting the value of categorising speeds. Within the 100km/hr zone, based on the categories, a significant difference was found regarding the speed that males would be willing to drive (and still feel in control) relative to females. Specifically, the greatest proportion of males (30.4%) identified speeds within the 106-110km/hr category whereas the greatest proportion of females (38.1%) identified a lower speed, within the 101-105km/hr category, as the speed they would be willing to drive. No other significant differences emerged, however, either in relation to the definition of speeding reported for 100km/hr zones (i.e., males and females tended to identify a similar speed as indicative of speeding) nor for these same items as assessed in relation to the 60km/hr zones. For their responses to the possibility of being caught, males were significantly more likely than females to report that, if caught, a likely response they would have would be to think that they had still been driving safely. In contrast, females were significantly more likely than males to report thinking that their speeding had been unsafe and that they should not have been speeding. Females were also significantly more likely to report feeling embarrassed to tell important others about having received a speeding infringement than males. The findings are discussed in terms of their implications for developing well-targeted advertising messages aimed at discouraging drivers’ from speeding.
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18.1 Antibiotics 18.1.1 Introduction to bacteria 18.1.2 Introduction to antibiotics 18.1.3 Inhibitors of bacterial cell wall synthesis 18.1.3.1 β-Lactams 18.1.3.2 Glycopeptides 18.1.4 Inhibitors of bacterial protein synthesis 18.1.4.1 Tetracyclines 18.1.4.2 Aminoglycosides 18.1.4.3 Chloramphenicol 18.1.4.4 Macrolides 18.1.4.5 Lincosamides 18.1.4.6 Oxalazidones 18.1.5 Inhibitors of DNA synthesis 18.2. Anti-tuberculotic drugs 18.2.1 Introduction 18.2.2 Isoniazid 18.2.3 Ethambutol 18.2.4 Rifamycin 18.2.5 Pyrazinamide 18.3. Anti-viral drugs 18.3.1 Introduction to viruses 18.3.2 Drugs used to treat herpesviruses 18.3.3 Drugs used to treat the flu 18.3.4 Drugs used to treat HIV/AIDS 18.4. Antifungal drugs 18.4.1 Introduction to Fungi 18.4.2 Antifungal drugs