Description: We present initial estimates of the physical properties of meteoric and marine ice in Larsen C ice shelf, Antarctic Peninsula, as derived from quality factor (Q) and amplitude-versus-angle (AVA) analysis of reflection-seismic datasets. The data were acquired during the 2008-09 austral summer in the south-eastern sector of the ice shelf, using explosive sources deployed in shallow shot holes, and 48 vertical-component 100 Hz geophones. 24 of these phones were installed horizontally and transverse to the acquisition line, such that compressional (P), verticallypolarised shear (SV) and horizontally-polarised shear (SH) could be recorded. The recorded data are rich in reflection events, with different phases identifiable as primary and multiple P-waves, SV- and SH-waves, and also P to SV mode conversions. The AVA character of these reflections is applied in a joint inversion, with a Bayesian statistical analysis used to obtain best-fit densities and wavelet velocities for the meteoric and marine ice, which allows estimates of the ices’ Young’s moduli and Poisson’s ratios. We further use prestack Q inversion (PSQI) to determine P- and S-wave quality factors for the two ice types, and consider these in terms of ice temperature and permeability. Our estimates of the physical properties of the meteoric and marine ices will ultimately be used to inform predictive models of the flow and fracture mechanics of Larsen C Ice Shelf.

Description: Cyclin-dependent kinase 1 (Cdk1) controls cell proliferation and is inhibited by promising anticancer agents, but its mode of action and the consequences of its inhibition are incompletely understood. Cdk1 promotes S- and M-phases during the cell-cycle but also suppresses endoreduplication, which is associated with polyploidy and genome instability. The complexity of Cdk1 regulation has made it difficult to determine whether these different roles require different thresholds of kinase activity and whether the surge of activity as inhibitory phosphates are removed at mitotic onset is essential for cell proliferation. Here, we have used chemical genetics in a human cell line to address these issues. We rescued cells lethally depleted of endogenous Cdk1 with an exogenous Cdk1 conferring sensitivity to one ATP analogue inhibitor (1NMPP1) and resistance to another (RO3306). At no 1NMPP1 concentration was mitosis in rescued clones prevented without also inducing endoreduplication, suggesting that these two key roles for Cdk1 are not simply controlled by different Cdk1 activity thresholds. We also rescued RO3306-resistant clones using exogenous Cdk1 without inhibitory phosphorylation sites, indicating that the mitotic surge of Cdk1 activity is dispensable for cell proliferation. These results suggest that the basic mammalian cycle requires at least some qualitative changes in Cdk1 activity and that quantitative increases in activity need not be rapid. Furthermore, the viability of cells that are unable to undergo rapid Cdk1 activation, and the strong association between endoreduplication and impaired proliferation, may place restrictions on the therapeutic use of a Cdk1 inhibitors.

Description: Preliminary investigations suggest biological geotextiles could be an effective and inexpensive soil conservation method, with enormous global potential. However, limited quantitative data are available on the erosion-reducing effects of biological geotextiles. Therefore, the objective is to evaluate the effectiveness of biological geotextiles in reducing runoff and soil loss under controlled laboratory conditions and under field conditions reflecting continental, temperate and tropical environments. In laboratory experiments, interrill runoff, interrill erosion and concentrated flow erosion were simulated using various rainfall intensities, flow shear stresses and slope gradients. Field plot data on the effects of biological geotextiles on sheet and rill erosion were collected in several countries (UK, Hungary, Lithuania, South Africa, Brazil, China and Thailand) under natural rainfall. Overall, based on the field plot data, the tested biological geotextiles reduce runoff depth and soil loss rates on average by 46 per cent and 79 per cent, respectively, compared to the values for bare soil. For the field and laboratory data of all tested geotextiles combined, no significant difference in relative runoff depth between field measurements and interrill laboratory experiments is observed. However, relative soil loss rate for the concentrated flow laboratory experiments are significantly higher compared to the interrill laboratory experiments and the field plot measurements. Although this study points to some shortcomings of conducting laboratory experiments to represent true field conditions, it can be concluded that the range and the mean relative runoff depth and soil loss rate as observed with the field measurements is similar to those as observed with the interrill laboratory experiments. Copyright © 2011 John Wiley & Sons, Ltd.

Description: Available studies do not allow comparison and quantification of the effects of biological geotextiles on runoff and water erosion rates under different agro-environmental conditions. Hence, this paper addresses this issue by comparing runoff and soil loss data obtained from field experiments (using different types of biological geotextiles) conducted in the United Kingdom, Hungary, South Africa, China, Thailand and Vietnam. Palm leaf mats (Borassus and Buriti mats) were used in the European countries. In the UK, Borassus mats were used as whole plot cover (area coverage ∼76 per cent; termed Borassus completely covered to differentiate from the Borassus buffer strip plots) and as buffer zones (area coverage ∼10 per cent), whereas Buriti mats were used only as buffer zones (area coverage ∼10 per cent). Only Lala mats were used in South Africa. Elsewhere (China, Thailand and Vietnam) biological geotextiles were constructed using other indigenous local materials, such as bamboo, rice straw and maize stalks. Biological geotextiles were used on bare plots in South Africa and the European countries. In the UK, plots were maintained bare by need based herbicide spraying. However, in South Asia, different crops were grown on the geotextile-covered plots. Results suggest that biological geotextiles were very effective for soil erosion control in all locations and the effectiveness for decreasing soil erosion rates by water was in the range of ∼67–99 per cent. The effectiveness of biological geotextiles in reducing runoff volume was in the range of ∼26–81 per cent. In the UK, total runoff and soil loss (during 8 January 2007–6 May 2008; total precipitation = 1145.8 mm) from the Borassus (one metre wide) buffer zone plots (cover percentage ∼7.6 per cent) were, respectively, ∼81 and ∼93 per cent less than bare plots. In Hungary and China, plots with ∼38 and 22 per cent geotextile-cover, respectively, had ∼88 and 96 per cent less soil loss, than bare plots. In most months with low precipitation (depth) in Hungary and the UK, runoff volume was greater from plots with geotextile-cover than from bare soils. However, complete data sets indicate that in the UK and Hungary, runoff reduction by different treatments over bare plots ranged between ∼26 and 81 per cent. Results from the UK showed that plots with buffer strips of Borassus and Buriti mats had similar effects in reducing soil losses as completely covered plots of the Borassus mats. Thus, foreseeing biological geotextile-cover on vulnerable segments of the landscape is highly effective for soil erosion control. Copyright © 2011 John Wiley & Sons, Ltd.

Description: Ventricular fibrillation (VF) in the globally ischemic heart is characterized by a progressive electrical depression manifested as a decline in the VF excitation rate (VFR) and loss of excitability, which occur first in the subepicardium (Epi) and spread to the subendocardium (Endo). Early electrical failure is detrimental to successful defibrillation and resuscitation during cardiac arrest. Hyperkalemia and/or the activation of ATP-sensitive K + (K ATP ) channels have been implicated in electrical failure, but the role of these factors in ischemic VF is poorly understood. We determined the VFR-extracellular K + concentration ([K + ] o ) relationship in the Endo and Epi of the left ventricle during VF in globally ischemic hearts (Isch group) and normoxic hearts subjected to hyperkalemia (HighK group) or a combination of hyperkalemia and the K ATP channel opener cromakalim (HighK-Crom group). In the Isch group, Endo and Epi values of [K + ] o and VFR were compared in the early (0–6 min), middle (7–13 min), and late (14–20 min) phases of ischemic VF. A significant transmural gradient in VFR (Endo 〉 Epi) was observed in all three phases, whereas a significant transmural gradient in [K + ] o (Epi 〉 Endo) occurred only in the late phase of ischemic VF. In the Isch group, the VFR decrease and inexcitability started to occur at much lower [K + ] o than in the HighK group, especially in the Epi. Combining K ATP activation with hyperkalemia only shifted the VFR-[K + ] o curve upward (an effect opposite to real ischemia) without changing the [K + ] o threshold for asystole. We conclude that hyperkalemia and/or K ATP activation cannot adequately explain the heterogeneous electrical depression and electrical failure during ischemic VF.

Description: Waugh is correct1—we cannot completely prevent unscrupulous use of content with an open register. However, there is no evidence that people are using PROSPERO records to plunder others’ ideas and...

Description: Background The UK has the highest rate of teenage pregnancies in Western Europe, a fifth are repeat pregnancies. Unintended conceptions can result in emotional, psychological and educational harm to teenage girls, often with enduring implications for their life chances. Babies of teenage mothers have increased mortality in their first year and increased risk of poverty, educational underachievement and unemployment later in life, with associated societal costs. Methods and analysis We will conduct a streamed, mixed-methods systematic review to find and evaluate interventions designed to reduce repeat unintended teen pregnancies. Our aims are to identify  Who is at greater risk of repeat unintended pregnancies? Which interventions are effective, cost-effective, how they work, in what setting and for whom? What are the barriers and facilitators to intervention uptake? Traditional electronic database searches will be augmented by targeted searches for evidence ‘clusters’ and guided by an advisory group of experts and stakeholders. To address the topic's inherent complexities, we will use a highly structured, innovative and iterative approach combining methodological techniques tailored to each stream of evidence. Quantitative data will be synthesised with reference to Cochrane guidelines for public health interventions. Qualitative evidence addressing facilitators and barriers to the uptake of interventions, experience and acceptability of interventions will be synthesised thematically. We will apply the principles of realist synthesis to uncover theories and mechanisms underpinning interventions. We will conduct an integration and overarching narrative of findings authenticated by client group feedback. Ethics and dissemination We will publish the complete review in ‘Health Technology Assessment’ and sections in specialist peer-reviewed journals. We will present at national and international conferences in the fields of public health, reproductive medicine and review methodology. Findings will be fed back to service users and practitioners via workshops run by the partner collaborators. Trail registration number PROSPERO CRD42012003168. Cochrane registration number i=fertility/0068.

Description: Lyme disease has several important ophthalmic manifestations that are important to highlight.1 Self limiting follicular conjunctivitis is probably the most common early ocular manifestation and...