Copper phthalocyanine on InSb(111)A?interface bonding, growth mode and energy band alignment

Copper phthalocyanine on InSb(111)A?interface bonding, growth mode and energy band alignment, D.A. Evans, H.J. Steiner, S. Evans, R. Middleton, T.S. Jones, S. Park, T.U. Kampen, D.R.T. Zahn, G. Cabailh and I.T. McGovern, J. Phys.: Condens. Matter, 15, S2729?S2740, (2003)

Determination of the optical band-gap energy of cubic and hexagonal boron nitride using luminescence excitation spectroscopy

Sponsorship: EPSRC, STFC

Algebra Llinol - Cyflwyniad

Cyfieithiad yw'r llyfr hwn o Linear Algebra - An Introduction a ymddangosodd gyntaf yn 1978 ac a gyhoeddwyd gan y cwmni Van Nostrand Reinhold. Cafwyd Ail Argraffiad yn 1982 a dros y blynyddoedd bu nifer o ail brintiadau. Yn y cyfamser cyfieithwyd y llyfr i'r Groeg a Thwrceg. Er i'r llyfr gael ei ddefnyddio dros y blynyddoedd gan nifer o fyfyrwyr yn Aberystwyth a oedd yn cyflwyno eu gwaith yn Gymraeg, nid oedd ar gael yn y Gymraeg. Dyma, o'r diwedd, ymgais i wneud rhyw fath o iawn am hynny. Er bod y llyfr wedi bod allan o brint yn y Saesneg ers rhai blynyddoedd yn awr, mae'n amlwg ei fod yn dal i gael ei gymeradwyo mewn nifer o brifysgolion. Felly, y gobaith yw y bydd o ddefnydd. Efallai mai'r peth nesaf bydd ei gyfiethu'n ?l i'r Saesneg! Mae nifer o newidiadau yn y fersiwn hwn. Mae'n siwr bod nifer o gamgymeriadau ac efallai gwelliannau posibl i'r cyfieithu - byddwn yn ddiolchgar dderbyn unrhyw awgrymiadau. Gellir eu cyflwyno hefyd drwy Dr Gwion Evans o'r Adran Fathemateg, Prifysgol Aberystwyth.

Dafydd ap Gwilym.net

Edwards, Huw, et al., Golygiad newydd o 33 o gerddi Dafydd ap Gwilym, a chyfraniad 9,830 o eiriau i'r rhagymadrodd ar 'Y Cyd-destun llenyddol' (2007)

New instrumentation for micro-imaging X-ray absorption spectroscopy using optical detection methods

Poolton, Nigel; Towlson, B.M.; Hamilton, B.; Evans, D.A., (2006) 'New instrumentation for micro-imaging X-ray absorption spectroscopy using optical detection methods', Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 246(2) pp.445-451 RAE2008

Internal structure of copper(II)-phthalocyanine thin films on SiO2/Si substrates investigated by grazing incidence x-ray reflectometry

Jenkins, Tudor; Brieva, A.C.; Jones, D.G.; Evans, D.A., (2006) 'Internal structure of copper(II)-phthalocyanine thin films on SiO2/Si substrates investigated by grazing incidence x-ray reflectometry', Journal of Applied Physics 99 pp.73504 RAE2008

Synchrotron-laser interactions in hexagonal boron nitride: an examination of charge trapping dynamics at the boron K-edge

Poolton, Nigel; Towlson, B.M.; Hamilton, B.; Evans, D.A., (2006) 'Synchrotron-laser interactions in hexagonal boron nitride: an examination of charge trapping dynamics at the boron K-edge', New Journal of Physics 8 pp.76 RAE2008

A fully integrated multi-channel detector for electron spectroscopy

Langstaff, David; Bushell, A.; Chase, T.; Evans, D.A., (2005) 'A fully integrated multi-channel detector for electron spectroscopy', Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 238 pp.219-223 RAE2008 Synchrotron Radiation in Materials Science ? Proceedings of the 4th Conference on Synchrotron Radiation in Materials Science 4th Conference on Synchrotron Radiation in Materials Science

Synchrotron-laser pump-probe luminescence spectroscopy: Correlation of electronic defect states with x-ray absorption in wide-gap solids

Poolton, Nigel; Hamilton, B.; Evans, D.A., (2005) 'Synchrotron-laser pump-probe luminescence spectroscopy: Correlation of electronic defect states with x-ray absorption in wide-gap solids', Journal of Physics D: Applied Physics 38 pp.1478-1484 RAE2008

Modification of nitrogen remobilisation, grain fill and leaf senescence in maize (Zea mays L.) by transposon insertional mutagenensis in a protease gene

Donnison, I. S., Gay, A. P., Thomas, Howard, Edwards, K. J., Edwards, D., James, C. L., Thomas, A. M., Ougham, H. J. (2007). Modification of nitrogen remobilization, grain fill and leaf senescence in maize (Zea mays) by transposon insertional mutagenensis in a protease gene. New Phytologist, 173 (3), 481-494. Sponsorship: BBSRC RAE2008

Microwave-Assisted Biginelli Reaction

Excellent laboratory procedure for a small focused library of dihydropyrimidinones. Good example of a multicomponent reaction performed using microwave irradiation.

Spike avalanches exhibit universal dynamics across the sleep-wake cycle.

BACKGROUND: Scale-invariant neuronal avalanches have been observed in cell cultures and slices as well as anesthetized and awake brains, suggesting that the brain operates near criticality, i.e. within a narrow margin between avalanche propagation and extinction. In theory, criticality provides many desirable features for the behaving brain, optimizing computational capabilities, information transmission, sensitivity to sensory stimuli and size of memory repertoires. However, a thorough characterization of neuronal avalanches in freely-behaving (FB) animals is still missing, thus raising doubts about their relevance for brain function. METHODOLOGY/PRINCIPAL FINDINGS: To address this issue, we employed chronically implanted multielectrode arrays (MEA) to record avalanches of action potentials (spikes) from the cerebral cortex and hippocampus of 14 rats, as they spontaneously traversed the wake-sleep cycle, explored novel objects or were subjected to anesthesia (AN). We then modeled spike avalanches to evaluate the impact of sparse MEA sampling on their statistics. We found that the size distribution of spike avalanches are well fit by lognormal distributions in FB animals, and by truncated power laws in the AN group. FB data surrogation markedly decreases the tail of the distribution, i.e. spike shuffling destroys the largest avalanches. The FB data are also characterized by multiple key features compatible with criticality in the temporal domain, such as 1/f spectra and long-term correlations as measured by detrended fluctuation analysis. These signatures are very stable across waking, slow-wave sleep and rapid-eye-movement sleep, but collapse during anesthesia. Likewise, waiting time distributions obey a single scaling function during all natural behavioral states, but not during anesthesia. Results are equivalent for neuronal ensembles recorded from visual and tactile areas of the cerebral cortex, as well as the hippocampus. CONCLUSIONS/SIGNIFICANCE: Altogether, the data provide a comprehensive link between behavior and brain criticality, revealing a unique scale-invariant regime of spike avalanches across all major behaviors.

Risk factors for and estimated incidence of community-associated Clostridium difficile infection, North Carolina, USA.

We determined estimated incidence of and risk factors for community-associated Clostridium difficile infection (CA-CDI) among patients treated at 6 North Carolina hospitals. CA-CDI case-patients were defined as adults (>18 years of age) with a positive stool test result for C. difficile toxin and no hospitalization within the prior 8 weeks. CA-CDI incidence was 21 and 46 per 100,000 person-years in Veterans Affairs (VA) outpatients and Durham County populations, respectively. VA case-patients were more likely than controls to have received antimicrobial drugs (adjusted odds ratio [aOR] 17.8, 95% confidence interval [CI] 6.6-48] and to have had a recent outpatient visit (aOR 5.1, 95% CI 1.5-17.9). County case-patients were more likely than controls to have received antimicrobial drugs (aOR 9.1, 95% CI 2.9-28.9), to have gastroesophageal reflux disease (aOR 11.2, 95% CI 1.9-64.2), and to have cardiac failure (aOR 3.8, 95% CI 1.1-13.7). Risk factors for CA-CDI overlap with those for healthcare-associated infection.

Chemical and biological applications of digital-microfluidic devices

The advent of digital microfluidic lab-on-a-chip (LoC) technology offers a platform for developing diagnostic applications with the advantages of portability, reduction of the volumes of the sample and reagents, faster analysis times, increased automation, low power consumption, compatibility with mass manufacturing, and high throughput. Moreover, digital microfluidics is being applied in other areas such as airborne chemical detection, DNA sequencing by synthesis, and tissue engineering. In most diagnostic and chemical-detection applications, a key challenge is the preparation of the analyte for presentation to the on-chip detection system. Thus, in diagnostics, raw physiological samples must be introduced onto the chip and then further processed by lysing blood cells and extracting DNA. For massively parallel DNA sequencing, sample preparation can be performed off chip, but the synthesis steps must be performed in a sequential on-chip format by automated control of buffers and nucleotides to extend the read lengths of DNA fragments. In airborne particulate-sampling applications, the sample collection from an air stream must be integrated into the LoC analytical component, which requires a collection droplet to scan an exposed impacted surface after its introduction into a closed analytical section. Finally, in tissue-engineering applications, the challenge for LoC technology is to build high-resolution (less than 10 microns) 3D tissue constructs with embedded cells and growth factors by manipulating and maintaining live cells in the chip platform. This article discusses these applications and their implementation in digital-microfluidic LoC platforms. © 2007 IEEE.