Elsinore fault seismicity: The September 13, 1973, Agua Caliente Springs, California, earthquake series

A relatively small M_L = 4.8 earthquake and its aftershock series on the southern portion of the Elsinore Fault Zone in eastern San Diego County, California, provided a rare opportunity to study an area that has been subjected to variable tectonic interpretations in the past. Within 12 to 26 hours after the main shock, a network of four portable seismograph stations was established around the main event near Agua Caliente Springs to supplement the stations of the Southern California Seismographic Network. Four days after the main shock, seven additional portable seismograph stations were installed. In addition to the main event, 45 subsequent events were studied, ranging in magnitude from about 1.0 to 3.7. Of these, 36 could be termed aftershocks by their close proximity to the main event, whose proper location was determined by analysis of the aftershock series. Of the two branches of the Elsinore Fault in this region, the south branch is associated with the earthquake series. Focal mechanisms are consistent with right-lateral strike-slip along the south branch, with northeast dip at latitude 32°51′N. These conclusions are supported by hypocentral locations. Thrust activity on the two fault branches may be developing a horst between them, accounting for elevation and tilt changes observed near Agua Caliente

Two-Dimensional Infrared Spectroscopy of Antiparallel β-Sheet Secondary Structure

We investigate the sensitivity of femtosecond Fourier transform two-dimensional infrared spectroscopy to protein secondary structure with a study of antiparallel β-sheets. The results show that 2D IR spectroscopy is more sensitive to structural differences between proteins than traditional infrared spectroscopy, providing an observable that allows comparison to quantitative models of protein vibrational spectroscopy. 2D IR correlation spectra of the amide I region of poly-L-lysine, concanavalin A, ribonuclease A, and lysozyme show cross-peaks between the IR-active transitions that are characteristic of amide I couplings for polypeptides in antiparallel hydrogen-bonding registry. For poly-L-lysine, the 2D IR spectrum contains the eight-peak structure expected for two dominant vibrations of an extended, ordered antiparallel β-sheet. In the proteins with antiparallel β-sheets, interference effects between the diagonal and cross-peaks arising from the sheets, combined with diagonally elongated resonances from additional amide transitions, lead to a characteristic “Z”-shaped pattern for the amide I region in the 2D IR spectrum. We discuss in detail how the number of strands in the sheet, the local configurational disorder in the sheet, the delocalization of the vibrational excitation, and the angle between transition dipole moments affect the position, splitting, amplitude, and line shape of the cross-peaks and diagonal peaks.

Vibrational Spectra of a Mechanosensitive Channel

We report the simulated vibrational spectra of a mechanosensitive membrane channel in different gating states. Our results show that while linear absorption is insensitive to structural differences, linear dichroism and sum-frequency generation spectroscopies are sensitive to the orientation of the transmembrane helices, which is changing during the opening process. Linear dichroism cannot distinguish an intermediate structure from the closed structure, but sum-frequency generation can. In addition, we find that two-dimensional infrared spectroscopy can be used to distinguish all three investigated gating states of the mechanosensitive membrane channel.

Every child mattered in England: but what matters to children?

“Every Child Matters” under New Labour provided a framework for services for young children’s care and education. It was pushed aside by the Conservative led coalition and replaced by “More Great Childcare”. The UK as a signatory to the United Nations Convention on the Rights of the Child, and therefore has obligations for legislation, policy and curriculum, specifically with regard to children’s rights and participation. On the 25th anniversary of the UNCRC, in practice there may be different levels of participation employed to engage children’s views in the development of policy about them. This project set out to ask children about what “matters” to them. Ninety finalist Early Childhood Studies students worked as co-researchers in this project. Five themes are discussed highlighting the powerful thoughts and ideas of children. A range of ‘child-friendly’ methods were used to collect data from children including role-play, interviews, drawings and artefacts, and story-telling