Evidence submitted to the Independent Commission on Freedom of Information

The government set up the Independent Commission on Freedom of Information on 17 July 2015 to review the Freedom of Information Act 2000. The Commission held a public call for evidence and has reviewed the Act as it has developed in the 10 years since it came into force. After receiving the Commission’s final report, the government published a written ministerial statement to respond to the Commission’s recommendations. They agreed with the weight of evidence (including our submission) that FOI should not be curtailed

Signal Transduction in Sinapis alba Root Hairs: Auxins as External Messengers

In developing root hairs of Sinapis alba the effects of externally applied indole-3-acetic acid (IAA) and other auxins have been investigated with respect to membrane potential, membrane conductance, cytosolic Ca2 + and pH. Following a delay of roughly 30s, 10- 12 to lO- IO M IAA slowly hyperpolarize, 10- 7 M IAA rapidly depolarize the root hairs, while 10- 9 M has hardly an effect. We show that these voltage responses are not the result of a change in membrane conductance or permeability, but are presumably caused by a change in H+ ATPase activity. The other tested auxins and analogues yielded comparable effects, but with much lower effectivity (IAA > 1-NAA > 2,4-D ~ 2-NAA > 2,3-D). Cytosolic Ca2+ and pH were decreased during depolarization by 0.2 and 0.4 units, respectively. No such changes were observed during hyperpolarization or about 1 h after the first encounter of the root hairs with IAA. We propose that IAA is a natural external signal for roots while competing with neighboring organisms for nutrients and salts, and suggest a signal chain with the plasma membrane H+ ATPase as a target protein. The delay in response to IAA, the time dependency, and the extremely low effective IAA concentrations point to the existence of a IAA receptor. Since the IAA-induced shifts in cytosolic pH and Ca2+ occur simultaneously with the depolarization, the question whether these ions are cellular messengers and part of an IAA-triggered signal chain is critically discussed

The role of the plasma-membrane Ca2+-ATPase in ca2+ homeostasis in Sinapis alba root hairs

The regulation of cytosolic Ca2+ has been investigated in growing root-hair cells of Sinapis alba L. with special emphasis on the role of the plasmamembrane Ca2+-ATPase. For this purpose, erythrosin B was used to inhibit the Ca2+-ATPase, and the Ca2+ ionophore A23187 was applied to manipulate cytosolic free [Ca2+] which was then measured with Ca2+-selective microelectrodes. (i) At 0.01 M, A23187 had no effect on the membrane potential but enhanced the Ca2+ permeability of the plasma membrane. Higher concentrations of this ionophore strongly depolarized the cells, also in the presence of cyanide. (ii) Unexpectedly, A23187 first caused a decrease in cytosolic Ca2+ by 0.2 to 0.3 pCa units and a cytosolic acidification by about 0.5 pH units, (iii) The depletion of cytosolic free Ca2+ spontaneously reversed and became an increase, a process which strongly depended on the external Ca2+ concentration, (iv) Upon removal of A23187, the cytosolic free [Ca2+] returned to its steady-state level, a process which was inhibited by erythrosin B. We suggest that the first reaction to the intruding Ca2+ is an activation of Ca2+ transporters (e.g. ATPases at the endoplasmic reticulum and the plasma membrane) which rapidly remove Ca2+ from the cytosol. The two observations that after the addition of A23187, (i) Ca2+ gradients as steep as-600 mV could be maintained and (ii) the cytosolic pH rapidly and immediately decreased without recovery indicate that the Ca2+-exporting plasma-membrane ATPase is physiologically connected to the electrochemical pH gradient, and probably works as an nH+/Ca2+-ATPase. Based on the finding that the Ca2+-ATPase inhibitor erythrosin B had no effect on cytosolic Ca2+, but caused a strong Ca2+ increase after the addion of A23187 we conclude that these cells, at least in the short term, have enough metabolic energy to balance the loss in transport activity caused by inhibition of the primary Ca2+-pump. We further conclude that this ATPase is a major Ca2+ regulator in stress situations where the cytosolic Ca2+ has been shifted from its steady-state level, as may be the case during processes of signal transduction

An improved method for constructing and selectively silanizing double-barreled, neutral liquid-carrier, ion-selective microelectrodes

We describe an improved, efficient and reliable method for the vapour-phase silanization of multi-barreled, ion-selective microelectrodes of which the silanized barrel(s) are to be filled with neutral liquid ion-exchanger (LIX). The technique employs a metal manifold to exclusively and simultaneously deliver dimethyldichlorosilane to only the ion-selective barrels of several multi-barreled microelectrodes. Compared to previously published methods the technique requires fewer procedural steps, less handling of individual microelectrodes, improved reproducibility of silanization of the selected microelectrode barrels and employs standard borosilicate tubing rather than the less-conventional theta-type glass. The electrodes remain stable for up to 3 weeks after the silanization procedure. The efficacy of a double-barreled electrode containing a proton ionophore in the ion-selective barrel is demonstrated in situ in the leaf apoplasm of pea (Pisum) and sunflower (Helianthus). Individual leaves were penetrated to depth of ~150 μm through the abaxial surface. Microelectrode readings remained stable after multiple impalements without the need for a stabilizing PVC matrix

Density dependent composition of InAs quantum dots extracted from grazing incidence x-ray diffraction measurements.

Epitaxial InAs quantum dots grown on GaAs substrate are being used in several applications ranging from quantum communications to solar cells. The growth mechanism of these dots also helps us to explore fundamental aspects of self-organized processes. Here we show that composition and strain profile of the quantum dots can be tuned by controlling in-plane density of the dots over the substrate with the help of substrate-temperature profile. The compositional profile extracted from grazing incidence x-ray measurements show substantial amount of inter-diffusion of Ga and In within the QD as a function of height in the low-density region giving rise to higher variation of lattice parameters. The QDs grown with high in-plane density show much less spread in lattice parameter giving almost flat density of In over the entire height of an average QD and much narrower photoluminescence (PL) line. The results have been verified with three different amounts of In deposition giving systematic variation of the In composition as a function of average quantum dot height and average energy of PL emission.The authors would like to acknowledge the support of Department of Science and Technology (DST) for carrying out synchrotron experiments at Petra III, DESY, Germany through the DST-DESY project and the EPSRC, UK for financial support.This is the final version of the article. It first appeared from NPG via http://dx.doi.org/10.1038/srep1573

Digital Watchdogs? Data reporting and the traditional 'fourth estate' role for journalists

As governments throughout the world transition to storing and releasing vast amounts of numerical information digitally, journalists are increasingly using digital data reporting as an investigative tool to report on issues in the public interest and to hold government - elected officials and bureaucracy – to account. Through a series of qualitative interviews with data journalists in 17 countries, this article examines the impact that digital data reporting is having on the traditional role of journalism as a fourth estate. Findings suggest the emergence of digital data reporting as a key tool in accountability journalism and in informing and engaging the public. However, the failure of popular ‘tabloid’ journalism to engage with data journalism means that a new technologically adept and data-informed elite class is on the rise, with important implications for democratic processes in advanced societies