Solar modulation of atmospheric electrification through variation of the conductivity over thunderstorms

It is suggested that variations of the current in the global atmospheric electrical circuit can be produced through regulation of the resistance between the tops of thunderclouds and the ionosphere. Long- and short-term changes in the conductivity of this region occur due to changes in the ionization rate resulting from solar activity. Previous suggestions that the phenomena might be due to conductivity variations in the fair weather part of the world or an influx of space charge to the upper atmosphere are discussed and considered unlikely. It might be possible to test the proposed mechanism by measuring the temporal variation of the ionospheric potential during distributed solar periods. Another approach would be to measure simultaneously the variation in ionization rate and electric current over thunderstorms. Several ways in which changes in atmospheric electrification might influence other meteorological phenomena are mentioned

Twentieth century secular decrease in the atmospheric potential gradient

Current flowing in the global atmospheric electrical circuit (AEC) substantially decreased during the twentieth century. Fair-weather potential gradient (PG) observations in Scotland and Shetland show a previously unreported annual decline from 1920 to 1980, when the measurements ceased. A 25% reduction in PG occurred in Scotland 1920–50, with the maximum decline during the winter months. This is quantitatively explained by a decrease in cosmic rays (CR) increasing the thunderstorm-electrosphere coupling resistance, reducing the ionospheric potential VI. Independent measurements of VI also suggest a reduction of 27% from 1920–50. The secular decrease will influence fair weather atmospheric electrical parameters, including ion concentrations and aerosol electrification. Between 1920–50, the PG showed a negative correlation with global temperature, despite the positive correlation found recently between surface temperature and VI. The 1980s stabilisation in VI may arise from compensation of the continuing CR-induced decline by increases in global temperature and convective electrification

Search for solar signals in GOES imagery and cloud climatology analysis

The digitization and analysis of 16mm GOES IR imagery to identify spatial and temporal variation in clouds is discussed, along with a cloud climatology analysis. Recently added to the Interactive Graphics Package was a Computer Image Analysis System. This system allows many new imaging techniques. One of the possibilities is the analysis of overall light intensity variations in six 10 degree square boxes across the intertropical convergence zone. This technique is discussed, as is a preliminary analysis of unnormalized data

Afghanistan’s first citizen’s advice centres: a path to foreign aid success?

Recently, the international community pledged $15.2 billion in aid to help Afghanistan until 2020, with the UK’s promising £750m, succeeding their previous contribution of £180m a year from 2011 to 2015. How can the UK ensure that this new round of government-funded aid meets its main objectives: value for money, the creation of a more stable country, and improvement of people’s lives? The Afghanistan and Central Asian Association’s Citizens Advice Centres provide a pertinent example, write Tevye Markson and Kiera Brodie. The key is in the development of institutional memory and communication between actors, so that lessons are learnt and shared

The impact of contextual family risks on prisoners' children's behavioural outcomes and the potential protective role of family functioning moderators.

Research suggests that children of prisoners have an increased risk for behavioural and emotional problems. However, in a resilience approach, one should expect heterogeneous outcomes and thus apply a contextualized perspective. As this is rarely acknowledged in empirical research, the present study sought to fill this gap using data from the Fragile Families and Child Wellbeing study on 801 children of imprisoned fathers. We explored the extent to which cumulative family risks measured during the first year of life (e.g., poverty and mental health problems) predicted behavioural outcomes at age 9 and whether potentially protective aspects of family functioning moderated the impact of these risk factors. Cumulative risk significantly predicted behavioural outcomes, but the associations were weak. No strong evidence of moderation was found. At low risk, mother-child closeness moderated behavioural outcomes. There was also some evidence of moderation by accumulated protective factors. Potential implications for policy and practice and challenges for further research are discussed.The authors would like to thank the Economic and Social Research Council for providing funding for this research, the organisers of the Fragile Families and Child Wellbeing Study Summer Data Workshop 2013 for their introduction to the dataset and Steve Lainé for his technical support.This is the final version. It first appeared from Taylor & Francis via http://dx.doi.org/10.1080/17405629.2015.105037

The Molecular Clockwork of a Protein-Based Circadian Oscillator

The circadian clock of the cyanobacterium Synechococcuselongatus PCC 7942 is governed by a core oscillator consisting of the proteins KaiA, KaiB, and KaiC. Remarkably, circadian oscillations in the phosphorylation state of KaiC can be reconstituted in a test tube by mixing the three Kai proteins and adenosine triphosphate. The in vitro oscillator provides a well-defined system in which experiments can be combined with mathematical analysis to understand the mechanism of a highly robust biological oscillator. In this Review, we summarize the biochemistry of the Kai proteins and examine models that have been proposed to explain how oscillations emerge from the properties of the oscillator’s constituents.Molecular and Cellular Biolog

Morphogen gradient reconstitution reveals Hedgehog pathway design principles

In developing tissues, cells estimate their spatial position by sensing graded concentrations of diffusible signaling proteins called morphogens. Morphogen-sensing pathways exhibit diverse molecular architectures, whose roles in controlling patterning dynamics and precision have been unclear. In this work, combining cell-based in vitro gradient reconstitution, genetic rewiring, and mathematical modeling, we systematically analyzed the distinctive architectural features of the Sonic Hedgehog pathway. We found that the combination of double-negative regulatory logic and negative feedback through the PTCH receptor accelerates gradient formation and improves robustness to variation in the morphogen production rate compared with alternative designs. The ability to isolate morphogen patterning from concurrent developmental processes and to compare the patterning behaviors of alternative, rewired pathway architectures offers a powerful way to understand and engineer multicellular patterning