Advances in crosshole seismic reflection processing

In recent years there have been significant advances in the acquisition and processing of crosshole seismic reflection data, and the method has been shown to be a high resolution imaging technique. However, the fidelity of the final images produced by this technique needs to be considered carefully to avoid incorrect interpretation. This thesis concerns the imaging capability of crosshole surveys, as well as advances made in processing techniques for application to crosshole seismic reflection surveys. In a migrated seismic section, a meaningful image is only obtained if a range of dips around the local structural dip is sampled at each image point. For crosshole seismic reflection surveys, the distribution of dips sampled at an image point is controlled principally by the survey geometry, including source and receiver array lengths and their element spacings. By considering the dips sampled, the imaging capability of crosshole reflection surveying is discussed, with suggestions as to how to ensure optimal imaging of the target zone. To overcome problems encountered in applying standard processing procedures, two new processing techniques are presented which enhance the imaging potential of crosshole reflection seismics. Generalised Berryhill migration has been developed as a full generalised Kirchhoff migration to include the near-field term, with the aim of improving image accuracy close to the source and receiver arrays. 3-D f-k-k filtering is an improved method of wavefield separation for crosshole seismic data. Finally, the results of processing three types of dataset are presented. One is from a site in the Groningen gas field, another was acquired through a model interrogated at ultrasonic frequencies in a water tank, and the third type was acquired using coal exploration boreholes in Yorkshire. The results demonstrate the imaging capability of the crosshole reflection method, and the success of the two new processing schemes

Pharmacokinetics and efficacy of oral versus intravenous mixed-micellar phylloquinone (vitamin K-1) in severe acute liver disease

Background/Aims: In patients with severe acute liver dysfunction, i.v. phylloquinone (vitamin K-1) may be given to exclude vitamin K deficiency, rather than impaired hepatic synthesis of coagulation factors alone, as the cause of the coagulopathy. However, there have been no studies of the pharmacokinetics or efficacy of i.v. or oral K-1 in such patients.Methods: 49 adults with severe acute liver disease were randomised double-blind to a single 10 mg dose of i.v. or oral mixed-micellar K-1, or placebo. Serum levels of phylloquinone and undercarboxylated prothrombin (PIVKA-II) were assessed before and after treatment.Results: At admission, 13 patients (27 %) had either low serum K-1 levels or elevated PIVKA-II concentrations, indicative of subclinical vitamin K deficiency. In the 16 patients who received i.v. K-1, there was one (6 %) treatment failure (K-1 rise < 10 ng/ml above baseline), compared with 12 of the 15 (80 %) who received oral K, (P < 0.0001). One patient in the placebo group developed overt vitamin K deficiency.Conclusions: A minority of patients with severe acute liver dysfunction have subclinical vitamin K deficiency at the time of presentation, which is corrected by a single dose of i.v. K-1. The intestinal absorption of mixed-micellar K, is unreliable in adults with severe acute liver dysfunction. (c) 2004 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved

Changes to nurses’ practice environment over time

© 2016 John Wiley & Sons Ltd Aims: To examine changes in the nursing practice environment, retention-related factors, unit stability and patient care tasks delayed or left undone, over two periods between 2004 and 2013. Background: Positive nurse practice environments have been linked to nurse retention and care quality outcomes. Methods: The collection of the Practice Environment Scale of the Nursing Work Index, job satisfaction, intent to leave, unit instability and tasks delayed or not done at six acute-care hospitals across three Australian states, in two waves between 2004 and 2013; results from the two waves are compared. Results: On average, practice environment scores declined slightly; nurses reported a greater difficulty in finding another nursing position, lower intent to leave their current job and greater instability in their current position. Rates of delayed tasks increased over the period, whereas rates of tasks left undone have decreased over the period. Conclusions: The decline in nurses’ perceptions of the quality of the practice environment is disappointing, particularly given the protracted workforce shortages that have persisted. Significant organisational restructuring and turnover of nurse executives may have contributed to this decline. Implication for Nursing Management: Managers need to apply existing evidence to improve nurse practice environments and manage instability

'Every generation has to make its own women's movement'

In this interview Sheila Rowbotham talks to Jo Littler about her involvement in feminism and politics over several decades. This ranges across her role in the Women's Liberation Movement, left activism, historical scholarship, work with in the Greater London Council (GLC), involvement in the international homeworking movement and her secret life as a poet

Simultaneous targeting of multiple opioid receptors: a strategy to improve side-effect profile

n/

Location of the River Euphrates in the Late Miocene; dating of terrace gravel at Shireen, Syria

International audienceWe report gravel of the River Euphrates, capped by basalt that is Ar-Ar dated to ~9 Ma, at Shireen in northern Syria. This gravel, preserved by the erosion-resistant basalt, allows us for the first time to reconstruct the history of this major river during the Late Miocene. In response to progressive regional surface uplift, the Euphrates extended SE by ~800 km between the early Middle Miocene, when the coast was near Kahramanmara? in southern Turkey, and the Pliocene, when it lay in western Iraq, east of the Arabian Platform uplands

Feminist Solidarities: Theoretical and Practical Complexities

This article considers the resurgence of interest in feminist solidarity in theory and practice in the contemporary moment in the United States and UK. What does feminist solidarity mean, what forms is it taking, and how might it proliferate? We begin by mapping the changing inflections of solidarity in recent feminist cultural theory, highlighting the range of theoretical components, investments and emphases. Next, we consider the various forms of solidarity presented and created by the Women’s March and the Women’s Strike, analysing the differences in terms of the extent of their reach and their political economy. We argue that both phenomena can be understood as reactions to, firstly, several decades of neoliberal impoverishment, which have now exposed neoliberal iterations of feminism as fundamentally inadequate; and secondly, and relatedly, the arrival of misogynistic and reactionary forms of nationalism. Finally, we show that different approaches to feminist solidarity, as well as an expansion of alliances, are necessary in order to extend contemporary feminism as an effective and large‐scale project. We therefore argue that feminist solidarity needs to retain its genealogical roots in left politics whilst being as plural as possible in practice

Selective hydrogenation of nitro compounds to amines by coupled redox reactions over a heterogeneous biocatalyst

Cleaner synthesis of amines remains a key challenge in organic chemistry because of their prevalence in pharmaceuticals, agrochemicals and synthetic building blocks. Here, we report a different paradigm for chemoselective hydrogenation of nitro compounds to amines, under mild, aqueous conditions. The hydrogenase enzyme releases electrons from H2 to a carbon black support which facilitates nitro-group reduction. For 30 nitroarenes we demonstrate full conversion (isolated yields 78 – 96%), with products including pharmaceuticals benzocaine, procainamide and mesalazine, and 4-aminophenol – precursor to paracetamol (acetaminophen). We also showcase gram-scale synthesis of procainamide with 90% isolated yield. We demonstrate potential for extension to aliphatic substrates. The catalyst is highly selective for reduction of the nitro group over other unsaturated bonds, tolerant to a wide range of functional groups, and exhibits excellent stability in reactions lasting up to 72 hours and full reusability over 5 cycles with a total turnover number over 1 million, indicating scope for direct translation to fine chemical manufacturing

Multiple Components of the VHL Tumor Suppressor Complex Are Frequently Affected by DNA Copy Number Loss in Pheochromocytoma

Pheochromocytomas (PCC) are rare tumors that arise in chromaffin tissue of the adrenal gland. PCC are frequently inherited through predisposing mutations in genes such as the von Hippel-Lindau (VHL) tumor suppressor. VHL is part of the VHL elongin BC protein complex that also includes CUL2/5, TCEB1, TCEB2, and RBX1; in normoxic conditions this complex targets hypoxia-inducible factor 1 alpha (HIF1A) for degradation, thus preventing a hypoxic response. VHL inactivation by genetic mechanisms, such as mutation and loss of heterozygosity, inhibits HIF1A degradation, even in the presence of oxygen, and induces a pseudohypoxic response. However, the described <10% VHL mutation rate cannot account for the high frequency of hypoxic response observed. Indeed, little is known about genetic mechanisms disrupting other complex component genes. Here, we show that, in a panel of 171 PCC tumors, 59.6% harbored gene copy number loss (CNL) of at least one complex component. CNL significantly reduced gene expression and was associated with enrichment of gene targets controlled by HIF1. Interestingly, we show that VHL-related renal clear cell carcinoma harbored disruption of VHL alone. Our results indicate that VHL elongin BC protein complex components other than VHL could be important for PCC tumorigenesis and merit further investigation

Learning through social spaces: migrant women and lifelong learning in post-colonial London

This article shows how migrant women engage in learning through social spaces. It argues that such spaces are little recognised, and that there are multiple ways in which migrant women construct and negotiate their informal learning through socialising with other women in different informal modes. Additionally, the article shows how learning is shaped by the socio-political, geographical and multicultural context of living in London, outlining ways in which gendered and racialised identities shape, construct and constrain participation in lifelong learning. The article shows that one way in which migrant women resist (post)colonial constructions of difference is by engaging in informal and non-formal lifelong learning, arguing that the benefits are (at least) two-fold. The women develop skills (including language skills) but also use their informal learning to develop what is referred to in this article as 'relational capital'. The article concludes that informal lifelong learning developed through social spaces can enhance a sense of belonging for migrant women