5,518 research outputs found
Holocene Relative Sea-Level Changes from Near-, Intermediate-, and Far-Field Locations
No full textHolocene relative sea-level (RSL) records exhibit spatial and temporal variability that arises mainly from the interaction of eustatic (land ice volume and thermal expansion) and isostatic (glacio- and hydro-) factors. We fit RSL histories from near-, intermediate-, and far-field locations with noisy-input Gaussian process models to assess rates of RSL change. Records from near-field regions (e.g., Antarctica, Greenland, Canada, Sweden, and Scotland) reveal a complex pattern of RSL fall from a maximum marine limit due to the net effect of eustatic sea-level rise and glacio-isostatic uplift with rates of RSL fall as great as -69 ± 9 m/ka. Intermediate-field regions (e.g., mid-Atlantic and Pacific coasts of the United States, Netherlands, Southern France, St. Croix) display variable rates of RSL rise from the cumulative effect of isostatic and eustatic factors. Fast rates of RSL rise (up to 10 ± 1 m/ka) are found in the early Holocene in regions near the center of forebulge collapse. Far-field RSL records exhibit a mid-Holocene highstand, the timing (between 8 and 4 ka) and magnitude (between <1 and 6 m) of which varies among South America, Africa, Asia and Oceania regions.Peer reviewe
"I don’t really like tedious, monotonous work": working-class young women, service sector employment and social mobility in contemporary Russia
No full textThis article contributes a global perspective to the emerging literature on girlhood in western contexts by examining the changing shape of transitions to adulthood amongst working-class young women in St. Petersburg, Russia. As in many western countries, new forms of service sector employment and an increasingly accessible higher education system appear to offer young women new prospects for social mobility. In contrast to the increasingly impoverished and denigrated traditional pathways into work, the young women in the study derive significant value from these new opportunities, constructing narratives of self-actualisation and approximating notions of respectable femininity. Nevertheless, actual social mobility is elusive, as familiar patterns of classed and gendered stratification limit their prospects. Despite its specificity, the case thus further illustrates the limited nature of the transformations available to young women through the new forms of education and work characteristic of global neoliberal contexts
Data supporting: Scuffing mechanisms of EN-GJS 400-15 spheroidal graphite cast iron against a 52100 bearing steel in a PAO lubricated reciprocating contact
No full textThis data supports the following publication (see below for paper abstract):
Kamps, T.J., Walker, J.C., Wood, R.J., Lee, P.M. and Plint, A.G. (2017) Scuffing mechanisms of EN-GJS 400-15 spheroidal graphite cast iron against a 52100 bearing steel in a PAO lubricated reciprocating contact. Wear, 1-16
Scuffing of the automotive piston ring on liner contact is likely to increase due to engine downsizing and the use of low viscosity engine oils to achieve greater fuel efficiency. This work investigated the scuffing mechanism of EN-GJS 400-15 spheroidal graphite cast iron caused by reciprocating sliding of a 52100 roller bearing element lubricated with PAO base oil.
The contact was conditioned at 100N and 15 Hz over a stroke of 25 mm at 180 oC. Subsequently the load was incremented in 100 N/min steps at 5 minute intervals until severe scuffing occurred, indicated by a rapid rise in the average friction coefficient. High speed friction was used to determine the onset of mild and severe scuffing. Stylus and 3D optical profilometery revealed that mild scuffing produced a smooth surface with small cracks compared to the severe scuffed surface which contained adhesive wear craters of 40 ?m in depth. Focused ion beam cross-sections of the mild scuffed surface and EDS analysis of the microstructure indicated that cracks were initiated by dross inclusions with a similar morphology to flake graphite. The transition to severe scuffing occurred at 700N when crack networks facilitated adhesive transfer of cast iron material to the counter-surface.</span
Supplemental Material, PAChallenge-TeamChallengeSupplementaryTable - Evaluation of a Worksite-Based Small Group Team Challenge to Increase Physical Activity
No full textSupplemental Material, PAChallenge-TeamChallengeSupplementaryTable for Evaluation of a Worksite-Based Small Group Team Challenge to Increase Physical Activity by Jessica M. Tullar, Timothy J. Walker, Timothy F. Page, Wendell C. Taylor, Rolando Roman, and Benjamin C. Amick in American Journal of Health Promotion</p
An analog approach to interference suppression in ultra-wideband receivers
No full textBecause of the huge bandwidth of Ultra-Wideband (UWB) systems, in-band narrowband
interference may hinder receiver performance. In this dissertation, sources
of potential narrowband interference that lie within the IEEE 802.15.3a UWB bandwidth
are presented, and a solution is proposed. To combat interference in Multi-Band
OFDM (MB-OFDM) UWB systems, an analog notch filter is designed to be included
in the UWB receive chain. The architecture of the filter is based on feed-forward
subtraction of the interference, and includes a Least Means Squared (LMS) tuning
scheme to maximize attenuation. The filter uses the Fast Fourier Transform (FFT)
result for interference detection and discrete center frequency tuning of the filter. It
was fabricated in a 0.18 ������m process, and experimental results are provided. This is
the first study of potential in-band interference sources for UWB. The proposed filter
offers a practical means for ensuring reliable UWB communication in the presense of
such interference.
The Operational Transconductance Amplifier (OTA) is the predominant building
block in the design of the notch filter. In many cases, OTAs must handle input
signals with large common mode swings. A new scheme for achieving rail-to-rail
input to an OTA is introduced. Constant gm is obtained by using tunable level
shifters and a single differential pair. Feedback circuitry controls the level shifters
in a manner that fixes the common mode input of the differential pair, resulting in consistent and stable operation for rail-to-rail inputs. As the new technique avoids
using complimentary input differential pairs, this method overcomes problems such
as Common Mode Rejection Ratio (CMRR) and Gain Bandwidth (GBW) product
degradation that exist in many other designs. The circuit was fabricated in a 0.5������m
process. The resulting differential pair had a constant transconductance that varied
by only ������0.35% for rail-to-rail input common mode levels. The input common mode
range extended well past the supply levels of ������1.5V, resulting in only ������1% fluctuation
in gm for input common modes from -2V to 2V
Ordering our world: the quest for traces of temporal organization in autobiographical memory
No full textAn experiment examined the idea, derived from the Self Memory System model (Conway & Pleydell-Pearce, 2000), that autobiographical events are sometimes tagged in memory with labels reflecting the life era in which an event occurred. The presence of such labels should affect the ease of judgments of the order in which life events occurred. Accordingly, 39 participants judged the order of two autobiographical events. Latency data consistently showed that between-era judgments were faster than within-era judgments, when the eras were defined in terms of either: (a) college versus high school, (b) academic quarter within year, or (c) academic year within school. The accuracy data similarly supported the presence of a between-era judgment effect for the college versus high school dichotomy
Evaluating Research Impact through Open Access to Scholarly Communication
No full textScientific research is a competitive business – in order to secure funding, promotion and tenure researchers must demonstrate their work has impact in their field. To maximise impact researchers undertake high priority research, aim to get results first, and publish in the highest impact journals. The Internet now presents a new opportunity to the scholarly author seeking higher impact: s/he can now make their work instantly accessible on the Web through author self-archiving. This growing body of open access literature (coupled with new publishing models that make journals available for-free to the reader) maximises research impact by maximising the number of people who can read it, and making it available sooner. Open access also provides a new opportunity for bibliometric research. This thesis describes the relatively recent phenomenon of open access to research literature, tools that were built to collect and analyse that literature, and the results of analyses of the effect of open access and its effect on author behaviour. It shows that articles self-archived by authors receive between 50-250% more citations, that rapid pre-printing on the Web has dramatically reduced the peak citation rate from over a year to virtually instant and how citation-impact – now widely used for evaluation – can be expanded to include a new web metric of download impact
Narcissism distorts the fading affect bias in autobiographical memory
No full textThe Fading Affect Bias (FAB) occurs when the affect associated with personal events fades differentially across time: Positive affect fades slower than negative affect. Three studies examined whether the magnitude of the FAB is moderated by narcissism. Results from Study 1 (diary method, N = 26) showed that low narcissism participants evidenced a large FAB, but high narcissism participants evidenced a reversed FAB. Results from Study 2 (retrospective recall method, N = 110) showed that low narcissism participants evinced a large FAB, and that the FAB diminished or dissipated as narcissism increased. Results from Study 3 (retrospective recall method, N = 83) showed that high narcissists evinced a FAB when they recalled achievement-themed autobiographical events, but evinced a reversed FAB when they recalled communal-themed events. These findings occurred independently of event rehearsal frequency. Results are discussed in terms of the idea that emotion regulation efforts may be disrupted in narcissists
Polydorella prolifera Augener 1914
No full textPolydorella prolifera Augener, 1914 Type species for the genus. Type locality: Western Australia, Sharks Bay, South Passage, 9 m, 16 April 1905. S.W. Australian Expedition, 1905. Type material: Syntypes: ZMH V 10106 Slightly damaged. Location and author of most recently described material: Blake and Kudenov (1978). Recorded distribution: Australia: Western Australia (Shark Bay).Published as part of Walker, Lexie M, 2011, A review of the current status of the Polydora - complex (Polychaeta: Spionidae) in Australia and a checklist of recorded species, pp. 40-62 in Zootaxa 2751 on page 54, DOI: 10.5281/zenodo.20356
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