A casein kinase 1 prevents expulsion of the oocyte meiotic spindle into a polar body by regulating cortical contractility.

During female meiosis, haploid eggs are generated from diploid oocytes. This reduction in chromosome number occurs through two highly asymmetric cell divisions, resulting in one large egg and two small polar bodies. Unlike mitosis, where an actomyosin contractile ring forms between the sets of segregating chromosomes, the meiotic contractile ring forms on the cortex adjacent to one spindle pole, then ingresses down the length of the spindle to position itself at the exact midpoint between the two sets of segregating chromosomes. Depletion of casein kinase 1 gamma (CSNK-1) in Caenorhabditis elegans led to the formation of large polar bodies that contain all maternal DNA, because the contractile ring ingressed past the spindle midpoint. Depletion of CSNK-1 also resulted in the formation of deep membrane invaginations during meiosis, suggesting an effect on cortical myosin. Both myosin and anillin assemble into dynamic rho-dependent cortical patches that rapidly disassemble in wild-type embryos. CSNK-1 was required for disassembly of both myosin patches and anillin patches. Disassembly of anillin patches was myosin independent, suggesting that CSNK-1 prevents expulsion of the entire meiotic spindle into a polar body by negatively regulating the rho pathway rather than through direct inhibition of myosin

Stoichiometry control of sputtered CuCl thin films: Influence on ultraviolet emission properties

We demonstrate that the chemical composition of the sputtered CuCl thin films could be finely controlled by adjusting the bias to the substrate. The films deposited without any intentional bias were Cl rich (CuCl1+x), a bias of −22 V yielded stoichiometric CuCl, and a further increase in the negative bias resulted in Cl deficient films (CuCl1−x). The crystalline and optical properties were found to be associated with the chemical composition. Cl rich films showed a deep level green emission at around 515 nm in addition to ultraviolet (UV) excitonic emission. The stoichiometric films have higher optical quality, exhibiting a sharp UV emission at around 385 nm at room temperature, compared to nonstoichiometric samples. Visible luminescence related to deep level defects was not observed in the stoichiometric films. Changes in energy of the flux from the target and the subsequent ion bombardment on the substrate surface are correlated with the variations in chemical composition and their impact on the film microstructure and UV emission

Dynactin-dependent cortical dynein and spherical spindle shape correlate temporally with meiotic spindle rotation in Caenorhabditis elegans.

Oocyte meiotic spindles orient with one pole juxtaposed to the cortex to facilitate extrusion of chromosomes into polar bodies. In Caenorhabditis elegans, these acentriolar spindles initially orient parallel to the cortex and then rotate to the perpendicular orientation. To understand the mechanism of spindle rotation, we characterized events that correlated temporally with rotation, including shortening of the spindle in the pole-to pole axis, which resulted in a nearly spherical spindle at rotation. By analyzing large spindles of polyploid C. elegans and a related nematode species, we found that spindle rotation initiated at a defined spherical shape rather than at a defined spindle length. In addition, dynein accumulated on the cortex just before rotation, and microtubules grew from the spindle with plus ends outward during rotation. Dynactin depletion prevented accumulation of dynein on the cortex and prevented spindle rotation independently of effects on spindle shape. These results support a cortical pulling model in which spindle shape might facilitate rotation because a sphere can rotate without deforming the adjacent elastic cytoplasm. We also present evidence that activation of spindle rotation is promoted by dephosphorylation of the basic domain of p150 dynactin

Short-term effects of deep ploughing on soil C stocks following renewal of a dairy pasture in New Zealand

In New Zealand’s high producing permanent pastures the topsoil constitutes a large reservoir of soil organic carbon (SOC), which shows a marked stratification with depth. As consequence, sub-surface layers can contain 10 times less carbon than the surface soil. In permanent pastures with high carbon inputs, the formation and decomposition of these surface SOC stocks are often at equilibrium and C storage shows little change over time. Pastoral based dairy systems utilising ryegrass plus clover cultivars require renewal every 7-10 years to avoid reversion to less productive grasses. This may involve spring cultivation (either no-till, shallow till or full cultivation), summer forage cropping and autumn re-grassing. It has been hypothesised that SOC stocks can be increased by inverting the soil profile at pasture renewal through infrequent (once in 25-30 years) deep mouldboard ploughing (up to 30 cm depth). Increased C sequestration occurs when the new grass quickly rebuilds SOC stocks in the new topsoil (exposed low C sub-soil) at a rate faster than the decomposition of SOC in the rich former topsoil transferred to depth (now below 15 cm). However, benefits form accelerated C storage may be offset if crop and pasture production is adversely affected by the ploughing event (e.g., as result of compaction or excessive drainage). Hence, the aim of this work was to assess the short-term effects of infrequent inversion tillage of long-term New Zealand pastoral-based dairy soils under summer crop management and autumn re-grassing. An imperfectly drained Typic Fragiaqualf under dairy grazing was deep ploughed (approx. 25 cm) and re-sown with turnip in October 2016; other treatments included were shallow (< 10 cm) cultivation and no-till. The site was core sampled (0-40 cm) before cultivation and after 5 months of turnip growth to assess changes in SOC. Plant growth, herbage quality, and nutrient leaching were monitored during the 5-month period; root growth was assessed at the end of the crop rotation. Full cultivation transferred SOC below 10 cm depth, as expected. Soil bulk density decreased whereas root mass increased (10-20 cm depth; P < 0.05) under deep cultivation only. Besides, losses of mineral N were attenuated under deep tillage, resulting in a relative increase in crop yield. The potential for infrequent inversion tillage increasing soil C sequestration as a greenhouse gas (GHG) mitigation tool is currently being tested at other sites in New Zealand

The effect of radiosensitizers on the pharmacokinetics of melphalan and cyclophosphamide in the mouse.

Misonidazole (MISO) has been shown to affect the pharmacokinetics of both cyclophosphamide (CY) and melphalan (MEL) in WHT mice resulting in increased plasma levels of the cytotoxic drugs. The effect is not solely due to the reduction in body temperature observed with large single doses of MISO, as a change in MEL pharmacokinetics was still observed when the mice were maintained at 37 degrees C. Inhibition of cytotoxic drug metabolism may also be a possible mechanism. Such a pharmacokinetic effect could account for part of the potentiation of MEL and CY action observed in tumours with large single doses of MISO. However, a chronic low dosing schedule of MISO did not affect the plasma half-life of either cytotoxic drug, although a significant potentiation of each drug in combination with a chronic MISO dose has been obtained in some tumours. These results suggest that potentiation of chemotherapeutic drug action by MISO in the clinical situation is unlikely to be due to changes in drug pharmacokinetics

The use of neighbourhood intensity comparisons, morphological gradients and Fourier analysis for automated precipitate counting & Pendell¨osung fringe analysis in X-ray topography

Crystal distortions modify the propagation of X-rays in single crystal materials, and X-ray topography can be used to record these modifications on a film thus providing images of the distributions and nature of defects, dislocations, strains, precipitates, etc. in semiconductors. Small variations of contrast, which often need to be analysed can be rendered invisible. Furthermore, artefacts in the films must be removed. This study examines the use of advanced image analysis techniques applied to a selection of X-ray topographs in section transmission mode: (i) the automated counting of oxygen-related precipitates and (ii) the enhancement of Pendell¨osung fringes. The technique also succeeds in removing unwanted features in the original x-ray topographs such as vertical streaking due to collimating slit phase contrast and strain features near the surface due to the presence of integrated circuit process strains

Exploring New Product Portfolio Management decisions: The role of managers' dispositional traits

Cataloged from PDF version of article.Product strategy links to new product development (NPD) through new product portfolio management (NPPM). This dynamic decision process addresses the strategy implementation questions of identifying which new product ideas to pursue and their relative priorities. Despite the importance of NPPM in implementing product strategy, firms exhibit substantial performance-affecting differences. We investigate one potential source for such differences by examining the impact of managers' dispositional factors as a possible explanation. Using a case study research method, we examine differences in NPPM strategies and managers' revealed dispositional traits across three divisions of a single conglomerate firm operating in different business-to-business markets. Based on our analysis, we offer propositions relating managers' dispositions to NPPM strategy: analytic cognitive style is associated with balance, ambiguity tolerance is associated with strategic fit, and leadership style is associated with the relative weights applied to each dimension. © 2007 Elsevier Inc. All rights reserved

Resolving the nature of electronic excitations in resonant inelastic x-ray scattering

The study of elementary bosonic excitations is essential toward a complete description of quantum electronic solids. In this context, resonant inelastic X-ray scattering (RIXS) has recently risen to becoming a versatile probe of electronic excitations in strongly correlated electron systems. The nature of the radiation-matter interaction endows RIXS with the ability to resolve the charge, spin and orbital nature of individual excitations. However, this capability has been only marginally explored to date. Here, we demonstrate a systematic method for the extraction of the character of excitations as imprinted in the azimuthal dependence of the RIXS signal. Using this novel approach, we resolve the charge, spin, and orbital nature of elastic scattering, (para-)magnon/bimagnon modes, and higher energy dd excitations in magnetically-ordered and superconducting copper-oxide perovskites (Nd2CuO4 and YBa2Cu3O6.75). Our method derives from a direct application of scattering theory, enabling us to deconstruct the complex scattering tensor as a function of energy loss. In particular, we use the characteristic tensorial nature of each excitation to precisely and reliably disentangle the charge and spin contributions to the low energy RIXS spectrum. This procedure enables to separately track the evolution of spin and charge spectral distributions in cuprates with doping. Our results demonstrate a new capability that can be integrated into the RIXS toolset, and that promises to be widely applicable to materials with intertwined spin, orbital, and charge excitations

Evaluation of a patient and public involvement training programme for researchers at a large biomedical research centre in the UK

Objectives: To design, deliver and evaluate a programme of training workshops for biomedical researchers aimed at building confidence and skills in actively involving patients and the public (PPI) in research. Design: A bespoke programme of training workshops in PPI aimed at researchers. Setting: A large National Institute for Health Research Biomedical Research Centre in London and several partner organisations. Participants: 721 scientists, clinicians and research managers attending dedicated training in PPI at a major London NHS (National Health Service)–university partnership. Interventions: A programme of 72 training workshops, designed to build practical skills and confidence for researchers working with patients and the public in research, was delivered at a major research-active NHS:university partnership. An iterative approach was taken to the programme, with the content of the workshops continually reviewed and refreshed to respond to the needs of researchers. Surveys before, immediately following and 6 months after training investigated the impact on researchers’ confidence and skills in PPI work, and the kind of PPI they subsequently carried out. Results: Training brought about immediate marked increases in researchers’ self-reported confidence to carry out PPI activities within their research, and in their knowledge of good practice. The evaluation indicates that workshop attendees were more likely to involve patients in their research following training. Researchers tended to involve patients and the public in a range of areas, including input to study design and patient information, in particular. Conclusions: When positioned within a broader organisational strategy for PPI in research, such training has an important role to play in progressing PPI in a major research partnership. Training appeared to provide the confidence needed to carry out PPI which enabled further development of confidence and skills. Involving researchers who have attended the training in the ongoing development of the programme and bringing in patients to the training programme are key next steps