37 research outputs found
Donor-based imputation methods for admin data: How to replace the number of rooms question on the Census
The Census White Paper recommends removing the number of rooms question and to utilise administrative data instead. Previous research demonstrated that Valuation Office Agency (VOA) data can be used for this purpose in principal. However, users of Census micro-level data expect a utility dataset without missingness.
This research project explored whether VOA number of rooms variable is suitable to undergo edit and imputation (E&I) within the standard census framework (i.e. donor imputation). We examined how linked admin and survey data challenges assumptions underlying the E&I process. We linked the 2011 Census with VOA data and attempted to impute VOA number of rooms using auxiliary variables from the Census to predict the missing and inconsistent values. This includes the question of whether we should allow questionnaire data to be changed where they are inconsistent with admin data.
We demonstrated that it is possible to predict VOA number of rooms from census variables, despite some assumptions being partially violated (definitional and time-frame issues, the possibility of subpopulations in the data). This was true for missingness prior to linkage and missingness due to a data linkage failure. Additionally, we successfully tested the design principal of favouring survey data over alternative data where the two are inconsistent.
We observed that some local authorities had large percentages of imputed data, and there was an increase in the percentage of properties where VOA number of rooms was equal to census number of bedrooms. This affects end-user interpretation of the data.
The result is not a general endorsement that all linked survey-admin data can be effectively treated by standard E&I procedures. However, our research can be used as a blue print for other proof-of-concept studies on imputing admin data
Microreactor cells for high throughput x-ray absorption spectroscopy
High-throughput experimentation has been applied to X-ray Absorption spectroscopy as a novel route for increasing research productivity in the catalysis community. Suitable instrumentation has been developed for the rapid determination of the local structure in the metal component of precursors for supported catalysts. An automated analytical workflow was implemented that is much faster than traditional individual spectrum analysis. It allows the generation of structural data in quasi-real time. We describe initial results obtained from the automated high throughput (HT) data reduction and analysis of a sample library implemented through the 96 well-plate industrial standard. The results show that a fully automated HT-XAS technology based on existing industry standards is feasible and useful for the rapid elucidation of geometric and electronic structure of materials
Activation of [CrCl3{PPh2N(iPr)PPh2}] for the selective oligomerisation of ethene: a Cr K-edge XAFS study
The activation of the ethene tetramerisation catalyst system based upon [CrCl3(THF)3] and N(iPr)(PPh2)2 has been investigated in situ via the reaction of [CrCl3{PPh2N(R)PPh2}(THF)] 1a (R=iPr) with excess AlMe3 in toluene. The Cr K-edge XAFS spectrum of the solution freeze quenched after 1 min reaction time indicated monomethylation of the metal with the resultant product being [CrClMe(ClAlCl3){PPh2N(R)PPh2}(THF)] 4a (R=iPr). After 5 minutes reaction time the XAFS spectra indicate that ~50% of 4a had been converted to a Cr(II) species, with the central core being high spin [CrCl2{PPh2N(R)PPh2}] 7a (R=iPr); a similar species, [CrClMe{PPh2N(R)PPh2}] 9a (R=iPr) was observed as its adduct with AlMe3 (10a) (R=iPr) when spectra were recorded on samples maintained a room temperature. Detailed analysis (EXAFS and XANES) indicated that 7a and 9a are stabilised by adduct formation of a Cr-Cl bond to the Lewis acids B(C6F5)3 and AlMe3, respectiveley. Modelling with DFT methods indicated that five-coordination was achieved, respectively by Cr-F (11a) and Cr-C (10a) interactions. In the presence of [Ph3C][Al{OC(tBuF)3}4], the Cr XAFS of the room temperature solution was inconsistent with the maintenance of a phosphine complex, but could be modelled with a site like [Cr2Me8]4- {Cr-Cr 2.01(2), Cr-C 2.14(4)}, thus demonstrating considerable variation in the effects of differing Lewis acids
Sufficient Conditions for Intractability over Black-Box Groups: Generic Lower Bounds for Generalized DL and DH Problems
The generic (aka. black-box) group model is a valuable methodology for analyzing the computational hardness of number-theoretic problems used in cryptography. Since the properties ensuring generic hardness have not been well-studied and formalized yet, for each newly proposed problem an entire hardness proof has to be done from scratch. In this work we identify criteria that guarantee the hardness of generalized DL and DH problems in an extended generic group model where algorithms are allowed to perform any operation representable by a polynomial function. Assuming our conditions are satisfied, we are able to provide negligible upper bounds on the success probability of such algorithms. As useful means for the formalization of definitions and conditions we explicitly relate the concepts of generic algorithms and straight-line programs that have only been used independently in cryptography so far
A trait-based trade-off between growth and mortality: Evidence from 15 tropical tree species using size-specific relative growth rates
A life-history trade-offbetween low mortality in the dark and rapid growth in the light is one of the most widely accepted mechanisms underlying plant ecological strategies in tropical forests. Differences in plant functional traits are thought to underlie these distinct ecological strategies; however, very few studies have shown relationships between functional traits and demographic rates within a functional group. We present 8 years of growth and mortality data from saplings of 15 species of Dipterocarpaceae planted into logged-over forest in Malaysian Borneo, and the relationships between these demographic rates and four key functional traits: wood density, specific leaf area (SLA), seed mass, and leaf C:N ratio. Species-specific differences in growth rates were separated from seedling size effects by fitting nonlinear mixed-effects models, to repeated measurements taken on individuals at multiple time points. Mortality data were analyzed using binary logistic regressions in a mixed-effects models framework. Growth increased and mortality decreased with increasing light availability. Species differed in both their growth and mortality rates, yet there was little evidence for a statistical interaction between species and light for either response. There was a positive relationship between growth rate and the predicted probability of mortality regardless of light environment, suggesting that this relationship may be driven by a general trade-offbetween traits that maximize growth and traits that minimize mortality, rather than through differential species responses to light. Our results indicate that wood density is an important trait that indicates both the ability of species to grow and resistance to mortality, but no other trait was correlated with either growth or mortality. Therefore, the growth mortality trade-offamong species of dipterocarp appears to be general in being independent of species crossovers in performance in different light environments. © 2014 The Authors
High Throughput In Situ XAFS Screening of Catalysts
We outline and demonstrate the feasibility of high-throughput (HT) in situ XAFS for synchrotron radiation studies. An XAS data acquisition and control system for the analysis of dynamic materials libraries under control of temperature and gaseous environments has been developed. The system is compatible with the 96-well industry standard and coupled to multi-stream quadrupole mass spectrometry (QMS) analysis of reactor effluents. An automated analytical workflow generates data quickly compared to traditional individual spectrum acquisition and analyses them in quasi-real time using an HT data analysis tool based on IFFEFIT. The system was used for the automated characterization of a library of 91 catalyst precursors containing ternary combinations of Cu, Pt, and Au on ?-Al2O3, and for the in situ characterization of Au catalysts supported on Al2O3 and TiO2
Resolving debris discs in the far-infrared: early highlights from the DEBRIS survey
We present results from the earliest observations of DEBRIS, a Herschel Key
Programme to conduct a volume- and flux-limited survey for debris discs in
A-type through M-type stars. PACS images (from chop/nod or scan-mode
observations) at 100 and 160 micron are presented toward two A-type stars and
one F-type star: beta Leo, beta UMa and eta Corvi. All three stars are known
disc hosts. Herschel spatially resolves the dust emission around all three
stars (marginally, in the case of beta UMa), providing new information about
discs as close as 11 pc with sizes comparable to that of the Solar System. We
have combined these data with existing flux density measurements of the discs
to refine the SEDs and derive estimates of the fractional luminosities,
temperatures and radii of the discs.Comment: to be published in A&A, 5 pages, 2 color figure
Resistance exercise initiates mechanistic target of rapamycin (mTOR) translocation and protein complex co-localisation in human skeletal muscle
The mechanistic target of rapamycin (mTOR) is a central mediator of protein synthesis in skeletal muscle. We utilized immunofluorescence approaches to study mTOR cellular distribution and protein-protein co-localisation in human skeletal muscle in the basal state as well as immediately, 1 and 3 h after an acute bout of resistance exercise in a fed (FED; 20 g Protein/40 g carbohydrate/1 g fat) or energy-free control (CON) state. mTOR and the lysosomal protein LAMP2 were highly co-localised in basal samples. Resistance exercise resulted in rapid translocation of mTOR/LAMP2 towards the cell membrane. Concurrently, resistance exercise led to the dissociation of TSC2 from Rheb and increased in the co-localisation of mTOR and Rheb post exercise in both FED and CON. In addition, mTOR co-localised with Eukaryotic translation initiation factor 3 subunit F (eIF3F) at the cell membrane post-exercise in both groups, with the response significantly greater at 1 h of recovery in the FED compared to CON. Collectively our data demonstrate that cellular trafficking of mTOR occurs in human muscle in response to an anabolic stimulus, events that appear to be primarily influenced by muscle contraction. The translocation and association of mTOR with positive regulators (i.e. Rheb and eIF3F) is consistent with an enhanced mRNA translational capacity after resistance exercise
Gendering the careers of young professionals: some early findings from a longitudinal study. in Organizing/theorizing: developments in organization theory and practice
Wonders whether companies actually have employees best interests at heart across physical, mental and spiritual spheres. Posits that most organizations ignore their workforce – not even, in many cases, describing workers as assets! Describes many studies to back up this claim in theis work based on the 2002 Employment Research Unit Annual Conference, in Cardiff, Wales