1,157 research outputs found

    Scattering from surfaces with different roughness scales, analysis and interpretation

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    Statistical analysis and physical interpretation of scattering from surfaces with different roughness scale

    Geochemical constraints on the origin of enigmatic cemented chalks, Norfolk, UK

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    Very hard cemented chalk stacks and crusts found locally in the upper part of the Cretaceous Chalk of north Norfolk, UK, are related to solution features. The solution features, mainly pipes and caves, formed after deposition of the overlying Middle Pleistocene Wroxham Crag, probably by routing of sub-glacial, or glacial, melt-waters derived from late Pleistocene glaciers. New geochemical (particularly stable isotope) data shows that cementation of the chalks, although related spatially to the solution features, was not caused by glacier-derived waters. The carbon isotope composition of the chalk cements is typically around -9.5‰, indicative of biologically active soils. Moreover, the oxygen isotope compositions of the cements, around -5‰, are incompatible with water d18O values much below -9 to -10‰ (which probably precludes isotopically negative glacier-derived water), as resulting palaeo-temperatures are below zero. Taken together, the isotope data suggest chalk cementation occurred under interglacial conditions similar to the present. Dissolved calcium carbonate for cementation came from dissolution of reworked chalk in overlying MIS 12 glacial tills

    THE RATE OF SUBLIMATION OF BENZOIC ACID

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    Identifying the Behavioral Intent to Use Social Media through the application of UTAUT in ANR and Turfgrass Extension

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    Little research exists on the role Extension Agricultural and Natural Resources professionals play in communicating information about new turfgrass cultivars. In an effort to analyze behavioral intentions related to social media and its use in the turfgrass industry, the researchers drew from the unified theory of acceptance and use of technology (UTAUT). A pilot instrument was developed to measure the intent of University researchers and county-based Extension professionals to use social media to disseminate turfgrass information, as well as their use of social media for seeking turfgrass information. This case study examined the role of county-based ANR Extension professionals across six states, analyzing their role as either creators or disseminators of ANR and turfgrass information, their intent to use social media, and their use of these communications to engage with ANR and turfgrass information. Findings of this study show that Facebook is the primary communications channel used by county-based Extension professionals. Further, it has been determined that the role of the county-based Extension professional in “creating” verses “using” previously established research-based information to disseminate to clientele is not well-defined. Broader implications include examination of performance expectations of county-based personnel related to their use of social media for communicating turfgrass information

    Being Good for Goodness Sake: The Influence of Family Involvement on Motivations to Engage in Small Business Social Responsibility

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    Small family and nonfamily firms are acknowledged to serve as important facilitators of social responsibility within their communities; however, both have received relatively little attention in the literature for these efforts or their motivation for undertaking them. Grounded in Enlightened Self-Interest (ESI) and intentions, we explore motivations for participation in socially responsible behaviors and the moderating effect of family involvement. We develop measures for small business social responsibility (SBSR), ESI, and SBSR intentions. Our analyses indicate positive direct effects exist for both SBSR intentions and ESI on engagement in SBSR. We find that family involvement strengthens the relationship between ESI and participation in civic SBSR, thus suggesting that family firms may be partially motivated to "do good" in visible forms of SBSR to protect their own interests

    Being Good for Goodness Sake: The Influence of Family Involvement on Motivations to Engage in Small Business Social Responsibility

    Get PDF
    Small family and nonfamily firms are acknowledged to serve as important facilitators of social responsibility within their communities; however, both have received relatively little attention in the literature for these efforts or their motivation for undertaking them. Grounded in Enlightened Self-Interest (ESI) and intentions, we explore motivations for participation in socially responsible behaviors and the moderating effect of family involvement. We develop measures for small business social responsibility (SBSR), ESI, and SBSR intentions. Our analyses indicate positive direct effects exist for both SBSR intentions and ESI on engagement in SBSR. We find that family involvement strengthens the relationship between ESI and participation in civic SBSR, thus suggesting that family firms may be partially motivated to "do good" in visible forms of SBSR to protect their own interests

    Get What You Give? An Examination of Enlightened Self-Interest, Philanthropic Intent, and Engagement in Philanthropy for Small Firm Owners

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    Prior researchers agree that small businesses are important community contributors due to their active engagement in broader social responsibility activities, such as philanthropy. Despite their purported importance to charitable giving and philanthropy, little is known about the factors that motivate small business owners’ decisions to engage in philanthropic giving. We integrate enlightened self-interest theory and the theory of planned behavior to examine how enlightened self-interest influences intentions to engage in philanthropy during start-up, which in turn impacts current levels of engagement in philanthropic activities. Our results suggest that intentions to engage in philanthropy at start-up do partially mediate the relationship between enlightened self-interest and engagement in philanthropy behaviors; thus, suggesting that entrepreneurs’ motivations grounded in enlightened self-interest influence intentions to engage in philanthropy and subsequent engagement in such activities

    Non-Ossicular Signal Transmission in Human Middle Ears: Experimental Assessment of the Acoustic Route with Perforated Tympanic Membranes

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    Direct acoustic stimulation of the cochlea by the sound-pressure difference between the oval and round windows (called the acoustic route ) has been thought to contribute to hearing in some pathological conditions, along with the normally dominant ossicular route. To determine the efficacy of this acoustic route and its constituent mechanisms in human ears, sound pressures were measured at three locations in cadaveric temporal bones [with intact and perforated tympanic membranes (TMs)]: (1) in the external ear canal lateral to the TM, PTM; (2) in the tympanic cavity lateral to the oval window, POW; and (3) near the round window, PRW. Sound transmission via the acoustic route is described by two concatenated processes: (1) coupling of sound pressure from ear canal to middle-ear cavity, H PCAV ≡ PCAV PTM, where PCAV represents the middle-ear cavity pressure, and (2) sound-pressure difference between the windows, HWPD ≡ (POW - PRW) PCAV. Results show that: H PCAV depends on perforation size but not perforation location; HWPD depends on neither perforation size nor location. The results (1) provide a description of the window pressures based on measurements, (2) refute the common otological view that TM perforation location affects the relative phase of the pressures at the oval and round windows, and (3) show with an intact ossicular chain that acoustic-route transmission is substantially below ossicular-route transmission except for low frequencies with large perforations. Thus, hearing loss from TM perforations results primarily from reduction in sound coupling via the ossicular route. Some features of the frequency dependence of H PCAV and HWPD can be interpreted in terms of a structure-based lumped-element acoustic model of the perforation and middle-ear cavities

    Acoustic Mechanisms that Determine the Ear-Canal Sound Pressures Generated by Earphones

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    In clinical measurements of hearing sensitivity, a given earphone is assumed to produce essentially the same sound-pressure level in all ears. However, recent measurements [Voss et al., Ear and Hearing (in press)] show that with some middle-ear pathologies, ear-canal sound pressures can deviate by as much as 35 dB from the normal-ear value; the deviations depend on the earphone, the middle-ear pathology, and frequency. These pressure variations cause errors in the results of hearing tests. Models developed here identify acoustic mechanisms that cause pressure variations in certain pathological conditions. The models combine measurement-based Thevenin equivalents for insert and supra-aural earphones with lumped-element models for both the normal ear and ears with pathologies that alter the ear\u27s impedance (mastoid bowl, tympanostomy tube, tympanic-membrane perforation, and a \u27high- impedance\u27 ear). Comparison of the earphones\u27 Thevenin impedances to the ear\u27s input impedance with these middle-ear conditions shows that neither class of earphone acts as an ideal pressure source; with some middle-ear pathologies, the ear\u27s input impedance deviates substantially from normal and thereby causes abnormal ear-canal pressure levels. In general, for the three conditions that make the ear\u27s impedance magnitude lower than normal, the model predicts a reduced ear-canal pressure (as much as 35 dB), with a greater pressure reduction with an insert earphone than with a supra-aural earphone. In contrast, the model predicts that ear-canal pressure levels increase only a few dB when the ear has an increased impedance magnitude; the compliance of the air-space between the tympanic membrane and the earphone determines an upper limit on the effect of the middle-ear\u27s impedance increase. Acoustic leaks at the earphone-to-ear connection can also cause uncontrolled pressure variations during hearing tests. From measurements at the supra-aural earphone-to-ear connection, we conclude that it is unusual for the connection between the earphone cushion and the pinna to seal effectively for frequencies below 250 Hz. The models developed here explain the measured pressure variations with several pathologic ears. Understanding these mechanisms should inform the design of more accurate audiometric systems which might include a microphone that monitors the ear-canal pressure and corrects deviations from normal
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