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UCL University College London Eprints (343,779 recursos)
UCL Eprints collects the work of UCL researchers and makes it freely available over the web, helping the worldwide scholarly community to discover UCL research. Institutional repositories like UCL Eprints complement the traditional academic publishing and scholarly communications processes. They raise the visibility of research and help to maximise its impact. UCL researchers are encouraged to deposit a copy of each journal article, conference paper, working paper, and any other research output, in the UCL Eprints at the earliest opportunity, ensuring that their research reaches as wide an audience as possible.

Mostrando recursos 181 - 200 de 343,438

181. Single-walled carbon nanotube composite inks for printed gas sensors: Enhanced detection of NO, NH, EtOH and acetone - Evans, GP; Buckley, DJ; Skipper, NT; Parkin, IP
The monitoring and detection of harmful vapours and precursor gases is an ever present concern to security services, industry and environmental groups. Recent advances in carbon nanotube based resistive sensors highlight potential applications in explosive detection, industrial and environmental monitoring. Metal oxide semiconducting (MOS) gas sensor technology also shows promise when applied in discriminatory arrays to form an electronic nose. Novel single-walled nanotube (SWNT)-metal oxide (SnO and WO) composite inks were synthesised and used to fabricate sensors with enhanced responses to low concentrations of NO, NH, acetone and EtOH vapours. Characterisation of the sensing material was accomplished by X-ray diffraction...

182. Deuteration around the ultracompact HII region Monoceros R2 - Trevino-Morales, SP; Pilleri, P; Fuente, A; Kramer, C; Roueff, E; Gonzalez-Garcia, M; Cernicharo, J; Gerin, M; Goicoechea, JR; Pety, J; Berne, O; Ossenkopf, V; Ginard, D; Garcia-Burillo, S; Rizzo, JR; Viti, S

183. Uso de la Metodología de Bond Graphs para el Modelaje y la Simulacion de Sistemas Fisicos Multidominios - Pichardo Almarza, CD; Delgado, M; Garcia, J; Rivera, R; Gerardi, M; Gil, JC

184. Mammalian cell culture test material generation for the assessment of primary recovery technologies. - Popova, D; Stonier, A; Pain, D; Titchener-Hooker, NJ; Farid, SS
Mammalian cell culture material is often difficult to produce accurately and reproducibly for downstream studies. This article presents a methodology for the creation of a set of cell culture test materials (CCTM) where key variables including cell density, cell viability, product and the host cell protein (HCP) load can be manipulated individually. This provides an effective and rapid method to create the required feeds for assessing the feasibility of primary recovery and purification technologies designed to cope with higher cell density cultures. The methodology was developed using a glutamine synthetase Chinese hamster ovary (GS-CHO) cell line cultured at 5-L and...

185. Possible signature of distant foreground in the Planck data - Yershov, VN; Orlov, VV; Raikov, AA
By using the Planck map of the cosmic microwave background (CMB) radiation we have checked and confirmed the existence of a correlation between supernova (SN) redshifts, $z_{\rm SN}$, and CMB temperature fluctuations at the SNe locations, $T_{\rm SN}$, which we previously reported for the Wilkinson Microwave Anisotropy Probe data. The Pearson correlation coefficient for the Planck data is $r=+0.38\pm 0.08$ which indicates that the correlation is statistically significant (the signal is about $5\sigma$ above the noise level). The correlation becomes even stronger for the type Ia subsample of SNe, $r_{\rm Ia}=+0.45\pm 0.09$, whereas for the rest of the SNe it...

186. Correlation of supernova redshifts with temperature fluctuations of the Cosmic Microwave Background - Yershov, VN; Orlov, VV; Raikov, AA
Redshifts of a supernova (SN) and gamma-ray burst (GRB) samples are compared with the pixel temperatures of the Wilkinson Microwave Anisotropy Probe (WMAP) seven-years data, the pixels locations corresponding to the SN and GRB sky coordinates. We have found a statistically significant correlation of the SN redshifts with the WMAP data, the average temperature deviation being +29.9 +-4.4 microK for the redshifts z ranging from 0.5 to 1.0 and +8.6 +-1.3 microK for z within the range (0.0,0.4). The latter value accords with the theoretical estimates for the distortion of the cosmic microwave background due to the integrated Sachs-Wolfe effect,...

187. The influence of lawyers' questions on witness accuracy, confidence, and reaction times and on mock jurors' interpretation of witness accuracy - Kebbell, MR; Evans, L; Johnson, SD
Two studies demonstrate the influence of lawyers' complex questions on mock-witness accuracy, confidence, and reaction times and on the interpretation of witness accuracy by mock jurors. In study one, 32 mock witnesses were shown a short film and then questioned either with lawyers' complex questions or simple alternatives. In Study 2, 20 mock jurors viewed video footage of the mock witnesses assigned to each of the two previous conditions and were asked to rate their confidence in the witnesses' answers. The findings of the two studies indicated that lawyers' use of confusing questions reduce not only accuracy but also speed...

188. Predictive mapping of crime by ProMap: Accuracy, units of analysis, and the environmental backcloth - Johnson, SD; Bowers, KJ; Pease, K; Birks, DJ
This chapter concerns the forecasting of crime locations using burglary as an example. An overview of research concerned with when and where burglaries occur is provided, with an initial focus on patterns of risk at the individual household level. Of central importance is evidence that as well as being geographically concentrated (at a range of geographic scales), burglary clusters in space and time more than would be expected if patterns of crime were simply the result of some places being more attractive to offenders than others. One theoretical framework regarding offender spatial decision making is discussed and consideration given to...

189. Stable and fluid hotspots of crime: Differentiation and identification - Johnson, SD; Bowers, KJ; Lab, SP
It has been known for some time that crime risk is unevenly distributed and that some geographic areas experience more crime than others. However, less attention has been given to the ebb and flow of crime hotspots and in particular the stability of crime problems. This is important as the identification of appropriate crime reduction responses should be informed by the timing and stability of crime problems as well as their location. This paper reviews recent work concerned with space-time patterns of crime and the implications of the findings for crime forecasting. Variation in the stability of crime hotspots is...

190. Closing off opportunities for crime: An evaluation of alley-gating - Bowers, KJ; Johnson, SD; Hirschfield, AFG
A new situational crime prevention measure recently introduced into Great Britain involves the fitting of gates to alleyways running along the back of terraced properties to restrict access to local residents and reduce opportunities for offenders. A number of quantitative techniques were used to assess the success of the intervention in reducing burglary in the City of Liverpool. The results demonstrate that, relative to a suitable comparison area, burglary was reduced by approximately 37%, there was a diffusion of benefit to properties in the surrounding areas, and the scheme was cost beneficial with a saving of £1.86 for every pound...

191. Victimisation and re-victimisation risk, housing type and area: A study of interactions - Bowers, KJ; Johnson, SD; Pease, K
It is often assumed that less ostensibly affluent homes (eg terraced housing) are more at risk than other types of housing (such as detached houses) of being burgled. The research reported here shows these patterns to be strongly influenced by the area in which houses are located. The results demonstrate that detached houses in deprived areas are particularly vulnerable to both victimisation and repeat victimisation. In such areas, detached houses are at over three times the risk of being burgled than terraced housing. Furthermore, the results demonstrate that the influences of area and housing type interact. For instance, detached houses...

192. Modelling and optimisation of the one-pot, multi-enzymatic synthesis of chiral amino-alcohols based on microscale kinetic parameter determination - Rios-Solis, L; Morris, P; Grant, C; Odeleye, AOO; Ward, JM; Dalby, PA; Baganz, F; Lye, GJ; Hailes, HC
Advances in synthetic biology are facilitating the de novo design of complex, multi-step enzymatic conversions for industrial organic synthesis. This work describes the integration of multi-step enzymatic pathway construction with enzyme kinetics and bioreactor modelling, in order to optimise the synthesis of chiral amino-alcohols using engineered Escherichia coli transketolases (TK) and the Chromobacterium violaceum transaminase (TAm). The specific target products were (2. S,3. S)-2-aminopentane-1,3-diol (APD) and (2. S,3. R)-2-amino-1,3,4-butanetriol (ABT). Kinetic models and parameters for each of the enzymatic steps were first obtained using automated microwell experiments. These identified the TK-catalysed conversions as being up to 25 times faster than...

193. Origins and functional consequences of somatic mitochondrial DNA mutations in human cancer - Ju, YS; Alexandrov, LB; Gerstung, M; Martincorena, I; Nik-Zainal, S; Ramakrishna, M; Davies, HR; Papaemmanuil, E; Gundem, G; Shlien, A; Bolli, N; Behjati, S; Tarpey, PS; Nangalia, J; Massie, CE; Butler, AP; Teague, JW; Vassiliou, GS; Green, AR; Du, M-Q; Unnikrishnan, A; Pimanda, JE; Teh, BT; Munshi, N; Greaves, M; Vyas, P; El-Naggar, AK; Santarius, T; Collins, VP; Grundy, R; Taylor, JA; Hayes, DN; Malkin, D; Foster, CS; Warren, AY; Whitaker, HC; Brewer, D; Eeles, R; Cooper, C; Neal, D; Visakorpi, T; Isaacs, WB; Bova, GS; Flanagan, AM; Futreal, PA; Lynch, AG; Chinnery, PF; McDermott, U; Stratton, MR; Campbell, PJ; Grp, ICGCBC; Grp, ICGCCMD; Grp, ICGCPC

194. Preformulated implementation intentions to promote colorectal cancer screening: A cluster-randomized trial - Lo, SH; Vart, G; von Wagner, C; Wardle, J; Good, A; Sheeran, P; Baio, G; Rainbow, S
Objective: To evaluate an intervention based on implementation intention principles designed to increase uptake of colorectal cancer screening, and to examine differential efficacy by socioeconomic deprivation. Method: In England, adults aged between 60 and 69 years are invited for biennial fecal occult blood testing. A test kit and an information leaflet are mailed to each individual by the "Hubs" that deliver the national screening program. In the intervention group, three preformulated implementation intentions, based on known barriers to carrying out the test, were added to the information leaflet. Over a 12-week period, each week was randomly allocated to either the...

195. Multiobjective evolutionary optimization in antibody purification process design - Allmendinger, R; Simaria, AS; Farid, SS
To contribute towards designing more cost-efficient, robust and flexible downstream processes for the manufacture of monoclonal antibodies (mAbs), a framework consisting of an evolutionary multiobjective optimization algorithm (EMOA) linked to a biomanufacturing process economics model is presented. The EMOA is tuned to discover sequences of chromatographic purification steps and column sizing strategies that provide the best trade-off with respect to multiple objectives including cost of goods per gram (COG/g), robustness in COG/g, and impurity removal capabilities. Additional complexities accounted for by the framework include uncertainties and constraints. The framework is validated on industrially relevant case studies varying in upstream and...

196. Virtual reality and consciousness inference in dreaming. - Hobson, JA; Hong, CC; Friston, KJ
This article explores the notion that the brain is genetically endowed with an innate virtual reality generator that - through experience-dependent plasticity - becomes a generative or predictive model of the world. This model, which is most clearly revealed in rapid eye movement (REM) sleep dreaming, may provide the theater for conscious experience. Functional neuroimaging evidence for brain activations that are time-locked to rapid eye movements (REMs) endorses the view that waking consciousness emerges from REM sleep - and dreaming lays the foundations for waking perception. In this view, the brain is equipped with a virtual model of the world...

197. Perception: A free-energy formulation - Friston, K

198. In vitro screen of prion disease susceptibility genes using the scrapie cell assay - Brown, CA; Schmidt, C; Poulter, M; Hummerich, H; Kloehn, P-C; Jat, P; Mead, S; Collinge, J; Lloyd, SE

199. Continuous Bioprocessing: The real thing this time? - Farid, SS; Thompson, B; Davidson, A

200. Atypical “seizure-like” activity in cortical reverberating networks in vitro can be caused by LPS-induced inflammation: A multi-electrode array study from a hundred neurons - Gullo, F; Donvito, G; Lecchi, M; Costa, B; Wanke, E; Amadeo, A; Constanti, A
We show here that a mild sterile inflammation induced by the endotoxin lipopolysaccharide (LPS), in a neuron/astrocyte/microglial cortical network, modulates neuronal excitability and can initiate long-duration burst events resembling epileptiform seizures, a recognized feature of various central nervous neurodegenerative, neurological and acute systemic diseases associated with neuroinflammation. To study this action, we simultaneously analyzed the reverberating bursting activity of a hundred neurons by using in vitro multi-electrode array methods. ∼5 h after LPS application, we observed a net increase in the average number of spikes elicited in engaged cells and within each burst, but no changes neither in spike waveforms...

 

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