UV Spectra and Excitation Delocalization in DNA: Influence of the Spectral Width

The singlet excited states of the model DNA duplex (dA)10.(dT)10 are studied. Calculations are performed in the exciton theory framework. Molecular dynamics calculations provide the duplex geometry. The dipolar coupling is determined using atomic transition charges. The monomer transition energies are simulated by Gaussian functions resembling the absorption bands of nucleosides in aqueous solutions. Most of the excited states are found to be delocalized over at least two bases and result from the mixing of different monomer states. Their properties are only weakly affected by conformational changes of the double helix. On average, the highest oscillator strength is carried by the upper eigenstates. The duplex absorption spectra are shifted a few nanometers to higher energies with respect to the spectra of noninteracting monomers. The states with larger spatial extent are located close to the maximum of the absorption spectrum

Exciton States of Dynamic DNA Double Helices: Alternating dCdG Sequences

The present communication deals with the excited states of the alternating DNA oligomer (dCdG)5·(dCdG)5 which correspond to the UV absorption band around 260 nm. Their properties are studied in the frame of the exciton theory, combining molecular dynamics simulations and quantum chemistry data. It is shown that the dipolar coupling undergoes important variations with the site and the helix geometry. In contrast, the energy of the monomer transitions within the double helix is not sensitive to the local environment. It is thus considered to be distributed over Gaussian curves whose maximum and width are derived from the experimental absorption spectra of nucleosides in aqueous solution. The influence of the spectral width on the excited state delocalization and the absorption spectra is much stronger than that of the oligomer plasticity. About half of the excited states are delocalized over at least two bases. Many of them result from the mixing of different monomer states and extend on both strands. The trends found in the simulated spectra, when going from non-interacting monomers to the duplex, are in agreement with experimental observations. Conformational changes enhance the diversity of the states which can be populated upon excitation at a given energy. The states with larger spatial extent are located close to the maximum of the absorption spectrum

Reassurance Policing and Signal Crimes

A reassurance function for policing was first considered by American psychologist Charles Bahn (1974: 338) as “feelings of safety that a citizen experiences when he knows that a police officer or patrol car is nearby.” This idea was taken forward in Britain by Martin Innes and colleagues in the early 2000s through the development of a signal crimes perspective. At this time, British policing implemented a National Reassurance Policing Programme (NRPP) where local policing priorities were decided through consultation with local communities. The impact of reassurance policing has since spread and the approach has also been considered in Australia, Belgium, the Netherlands, and Sweden. In this entry, the background to reassurance policing is considered with particular reference to the work of Charles Bahn and Martin Innes and colleagues. The development of a policy of reassurance policing in Britain is also examined. The successes and limitations of the approach are considered and three main issues identified: that reassurance needs to be a consideration for all policing; that increases in visible patrol need to be questioned (especially at a time of budget restraint); and that reassurance policing has the potential to be a model of democratic policing, but only if consultation is truly inclusive, for instance, including those that have been victimized and groups that have been targets of police activity such as young people, the homeless, and other minority and marginalized groups

Aproximación a la construcción del concepto de multiplicación en el marco del estudio de clases

Este artículo da cuenta de una investigación que se centró en dos aspectos confluyentes: el mejoramiento de la enseñanza del concepto de multiplicación, que los alumnos evidencian haber aprendido de modo inadecuado e incompleto, y el desarrollo profesional de profesores de educación básica de establecimientos de dependencia municipal. La investigación acción buscaba favorecer el desarrollo de las capacidades de los profesores para elaborar e implementar una propuesta de enseñanza efectiva del concepto de multiplicación en el marco de Estudio de Clases. El estudio se sustentó en los fundamentos teóricos de la Teoría de la Transposición Didáctica y el Estudio de Clases. Los resultados reportados muestran progresos de los profesores en la profundización en el concepto de multiplicación y en el mejoramiento de las capacidades de enseñanza para la construcción del concepto de multiplicación en los alumnos

A European lens upon adult and lifelong learning in Asia

In this article, we seek to assess the extent to which adult and lifelong learning policies and practices in Asia have distinctiveness by comparison to those found in western societies, through an analysis of inter-governmental, national and regional policies in the field. We also inform our study through the analysis of the work of organisations with an international remit with a specific focus on Asia and Europe. In one case, the Asia–Europe Meeting Lifelong Learning (ASEM LLL) Hub has a specific function of bringing together researchers in Asia and Europe. In another, the PASCAL Observatory has had a particular focus on one aspect of lifelong learning, that of learning cities, with a concentration in its work on Asia and Europe. We focus on learning city development as a particular case of distinction in the field. We seek to identify the extent to which developments in the field in Asia have influenced and have been influenced by practices elsewhere in world, especially in Europe, and undertake our analysis using theories of societal learning/the learning society, learning communities and life-deep learning. We complement our analysis through assessment of material contained in three dominant journals in the field, the International Journal of Lifelong Education, the International Review of Education and Adult Education Quarterly, each edited in the west

Harnessing person-generated health data to accelerate patient-centered outcomes research: the Crohn’s and Colitis Foundation of America PCORnet Patient Powered Research Network (CCFA Partners)

The Crohn’s and Colitis Foundation of America Partners Patient-Powered Research Network (PPRN) seeks to advance and accelerate comparative effectiveness and translational research in inflammatory bowel diseases (IBDs). Our IBD-focused PCORnet PPRN has been designed to overcome the major obstacles that have limited patient-centered outcomes research in IBD by providing the technical infrastructure, patient governance, and patient-driven functionality needed to: 1) identify, prioritize, and undertake a patient-centered research agenda through sharing person-generated health data; 2) develop and test patient and provider-focused tools that utilize individual patient data to improve health behaviors and inform health care decisions and, ultimately, outcomes; and 3) rapidly disseminate new knowledge to patients, enabling them to improve their health. The Crohn’s and Colitis Foundation of America Partners PPRN has fostered the development of a community of citizen scientists in IBD; created a portal that will recruit, retain, and engage members and encourage partnerships with external scientists; and produced an efficient infrastructure for identifying, screening, and contacting network members for participation in research

OBSERVATIONS ON NAVICULA THALLODES (BACILLARIOPHYCEAE), A BLADE-FORMING DIATOM FROM THE BERING SEA 1

A thallus-forming diatom, Navicula thallodes Proschkina-Lavrenko, previously known only from the original collection at Bering Island (U.S.S.R.), has been found at Amchitka Island in the Aleutians, Alaska. The most remarkable observation of the present report is that N. thallodes may form blades up to 50 cm long, which to our knowledge is the greatest length reported for a colonial diatom. SEM observations of this diatom are presented for the first time.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65176/1/j.1529-8817.1988.tb04487.x.pd