Measuring a cell's response to stress: the p53 pathway

The characterization of complex cellular responses to diverse stimuli can be studied by the use of emerging chip-based technologies

Anomalous Hall Effect in three ferromagnets: EuFe4Sb12, Yb14MnSb11, and Eu8Ga16Ge30

The Hall resistivity (Rho_xy), resistivity (Rho_xx), and magnetization of three metallic ferromagnets are investigated as a function of magnetic field and temperature. The three ferromagnets, EuFe4Sb12 (Tc = 84 K), Yb14MnSb11 (Tc = 53 K), and Eu8Ga16Ge30 (Tc = 36 K) are Zintl compounds with carrier concentrations between 1 x 10^21 cm^-3 and 3.5 x 10^21 cm^-3. The relative decrease in Rho_xx below Tc [Rho_xx(Tc)/Rho_xx(2 K)] is 28, 6.5, and 1.3 for EuFe4Sb12, Yb14MnSb11, and Eu8Ga16Ge30 respectively. The low carrier concentrations coupled with low magnetic anisotropies allow a relatively clean separation between the anomalous (Rho_'xy), and normal contributions to the measured Hall resistivity. For each compound the anomalous contribution in the zero field limit is fit to alpha Rho_xx + sigma_xy rho_xx^2 for temperatures T < Tc. The anomalous Hall conductivity, sigma_xy, is -220 +- 5 (Ohm^-1 cm^-1), -14.7 +- 1 (Ohm^-1 cm^-1), and 28 +- 3 (Ohm^-1 cm^-1) for EuFe4Sb12, Yb14MnSb11, and Eu8Ga16Ge30 respectively and is independent of temperature for T < Tc if the change in spontaneous magnetization (order parameter) with temperature is taken into account. These data are consistent with recent theories of the anomalous Hall effect that suggest that even for stochiometric ferromagnetic crystals, such as those studied in this article, the intrinsic Hall conductivity is finite at T = 0, and is a ground state property that can be calculated from the electronic structure.Comment: 22 pages, 13 figures Submitted to PR

Long-term prevalence and predictors of prolonged grief disorder amongst bereaved cancer caregivers: A cohort study

Context: The short-term impact of prolonged grief disorder (PGD) following bereavement is well documented. The longer term sequelae of PGD however are poorly understood, possibly unrecognized, and may be incorrectly attributed to other mental health disorders and hence undertreated. Objectives: The aims of this study were to prospectively evaluate the prevalence of PGD three years post bereavement and to examine the predictors of long-term PGD in a population-based cohort of bereaved cancer caregivers. Methods: A cohort of primary family caregivers of patients admitted to one of three palliative care services in Melbourne, Australia, participated in the study (n = 301). Sociodemographic, mental health, and bereavement-related data were collected from the caregiver upon the patient\u27s admission to palliative care (T1). Further data addressing circumstances around the death and psychological health were collected at six (T2, n = 167), 13 (T3, n = 143), and 37 months (T4, n = 85) after bereavement. Results: At T4, 5% and 14% of bereaved caregivers met criteria for PGD and subthreshold PGD, respectively. Applying the total PGD score at T4, linear regression analysis found preloss anticipatory grief measured at T1 and self-reported coping measured at T2 were highly statistically significant predictors (both p \u3c 0.0001) of PGD in the longer term. Conclusion: For almost 20% of caregivers, the symptoms of PGD appear to persist at least three years post bereavement. These findings support the importance of screening caregivers upon the patient\u27s admission to palliative care and at six months after bereavement to ascertain their current mental health. Ideally, caregivers at risk of developing PGD can be identified and treated before PGD becomes entrenched

Experimental Demonstration of Focal Plane Array Beamforming in a Prototype Radiotelescope

Focal plane arrays are being developed to provide dishes with a wide field of view for both the next generation of radiotelescopes and to retrofit existing large radiotelescopes. We describe a prototype radiotelescope, comprising a two dish interferometer with real-time digital beamformer that was built to study focal plane array systems. Two beamformer weightings were applied to the system: A normalized conjugate match and the maximum sensitivity (G/T). Both incorporate the uncorrelated noise from the receiver chains and the latter includes correlated noise from spillover and coupling in the array. A black box approach is taken where the assembled system is considered and the only accessible data is that typically available from an operational radiotelescope. This approach is particularly suitable for complex active antennas where there is insufficient knowledge of the system for beamformer weights to be set a priori. It also allows adaptation to changes such as electronic gain drift, partial failures and alterations in the environment

Does Epileptiform Activity Represent a Failure of Neuromodulation to Control Central Pattern Generator-Like Neocortical Behavior?

Rhythmic motor patterns in invertebrates are often driven by specialized "central pattern generators" (CPGs), containing small numbers of neurons, which are likely to be "identifiable" in one individual compared with another. The dynamics of any particular CPG lies under the control of modulatory substances, amines, or peptides, entering the CPG from outside it, or released by internal constituent neurons; consequently, a particular CPG can generate a given rhythm at different frequencies and amplitudes, and perhaps even generate a repertoire of distinctive patterns. The mechanisms exploited by neuromodulators in this respect are manifold: Intrinsic conductances (e.g., calcium, potassium channels), conductance state of postsynaptic receptors, degree of plasticity, and magnitude and kinetics of transmitter release can all be affected. The CPG concept has been generalized to vertebrate motor pattern generating circuits (e.g., for locomotion), which may contain large numbers of neurons - a construct that is sensible, if there is enough redundancy: that is, the large number of neurons consists of only a small number of classes, and the cells within any one class act stereotypically. Here we suggest that CPG and modulator ideas may also help to understand cortical oscillations, normal ones, and particularly transition to epileptiform pathology. Furthermore, in the case illustrated, the mechanism of the transition appears to be an exaggerated form of a normal modulatory action used to influence sensory processing

Optical interferometer in space

The present design concepts for a Laser Gravitational Wave Observatory in Space are described. Laser heterodyne distance measurements are made between test masses located in three spacecraft separated by roughly 10(exp 6) km. The major technology issues are: the reduction of spurious acceleration noise for the test masses to below 2 x 10(exp -15) cm/sq sec/Hz(0.5) from 10(exp -5) to 10(exp -3) Hz; and the measurement of changes in the difference of the antenna arm lengths to 5 x 10(exp -11) cm/Hz(0.5) from 10(exp -3) to 1 Hz with high reliability. The science objectives are: to measure discrete sinusoidal gravitational wave signals from individual sources with periods of 1 second to 1 day; to measure the stochastic background due to unresolved binaries; and to search for gravitational wave pulses with periods longer than 1 sec from possible exotic sources such as gravitational collapse of very massive objects

Social Movement Learning Research: International Comparative Perspectives on Challenges and the Current Status of the Field

Studies of social movements have a long and contradictory relationship with adult education research. In this symposium contributors address the question: What is the current status, themes and the potentials and limits of current social movement learning (SML) research internationally

Forage Quality Characteristics of \u3cem\u3eLotus tenuis\u3c/em\u3e, Narrow-Leaf Birdsfoot Trefoil

Narrow-leaf birdsfoot trefoil (Lotus tenuis Waldst. & Kit.) is a herbaceous perennial legume of Mediterranean origin, which can grow in saline and waterlogged environments (Teakle et al. 2010). If this species is to be cultivated in regions constrained by these abiotic factors, it is also vital that herbage produced has a forage quality acceptable for ruminant production. In addition, proanthocyanidin (PA) content is important, and legume species can cause animal production issues if PA content is low, (\u3c 0.02%), e.g. fro-thy bloat, or high (\u3e 5 %), e.g. decreased palatability and digestibility (Larkin et al. 1999). This study examined the PA content and forage quality of a range of L. tenuis accessions being evaluated for improved seed production and suitability for introduction into grazing systems where salinity and waterlogging are a common problem

The development of a simple multi-nodal tool to identify performance issues in existing commercial buildings

Australia’s building stock includes many older commercial buildings with numerous factors that impact energy performance and indoor environment quality. The built environment industry has generally focused heavily on improving physical building design elements for greater energy efficiency (such as retrofits and environmental upgrades), however there are noticeable ‘upper limits’ to performance improvements in these areas. To achieve a stepchange improvement in building performance, the authors propose that additional components need to be addressed in a whole of building approach, including the way building design elements are managed and the level of stakeholder engagement between owners, tenants and building managers. This paper focuses on the opportunities provided by this whole-of-building approach, presenting the findings of a research project undertaken through the Sustainable Built Environment National Research Centre (SBEnrc) in Australia. Researchers worked with a number of industry partners over two years to investigate issues facing stakeholders at base building and tenancy levels, and the barriers to improving building performance. Through a mixed-method, industry-led research approach, five ‘nodes’ were identified in whole-of-building performance evaluation, each with interlinking and overlapping complexities that can influence performance. The nodes cover building management, occupant experience, indoor environment quality, agreements and culture, and design elements. This paper outlines the development and testing of these nodes and their interactions, and the resultant multi-nodal tool, called the ‘Performance Nexus’ tool. The tool is intended to be of most benefit in evaluating opportunities for performance improvement in the vast number of existing low-performing building stock

Nanopore direct RNA sequencing maps the complexity of Arabidopsis mRNA processing and m6A modification

Understanding genome organization and gene regulation requires insight into RNA transcription, processing and modification. We adapted nanopore direct RNA sequencing to examine RNA from a wild-type accession of the model plant Arabidopsis thaliana and a mutant defective in mRNA methylation (m6A). Here we show that m6A can be mapped in full-length mRNAs transcriptome-wide and reveal the combinatorial diversity of cap-associated transcription start sites, splicing events, poly(A) site choice and poly(A) tail length. Loss of m6A from 3’ untranslated regions is associated with decreased relative transcript abundance and defective RNA 30 end formation. A functional consequence of disrupted m6A is a lengthening of the circadian period. We conclude that nanopore direct RNA sequencing can reveal the complexity of mRNA processing and modification in full-length single molecule reads. These findings can refine Arabidopsis genome annotation. Further, applying this approach to less well-studied species could transform our understanding of what their genomes encode