Statistical evaluation of the early-stage development of Jatropha energy plantations in Northeastern Mexico

A systematic evaluation of agricultural factors affecting the adaptation of the tropical oil plant Jatropha curcas L. to the semi-arid subtropical climate in Northeastern Mexico has been conducted. The factors studied include plant density and topology, as well as fungi and virus abundances. A multiple regression analysis shows that total fruit production can be well predicted by the area per plant and the total presence of fungi. Four common herbicides and a mechanical weed control measure were established at a dedicated test array and their impact on plant productivity was assessed.

Structure of the ROC domain from the Parkinson's disease-associated leucine-rich repeat kinase 2 reveals a dimeric GTPase

Mutations in leucine-rich repeat kinase 2 (LRRK2) are the most common cause of Parkinson's disease (PD). LRRK2 contains a Ras of complex proteins (ROC) domain that may act as a GTPase to regulate its protein kinase activity. The structure of ROC and the mechanism(s) by which it regulates kinase activity are not known. Here, we report the crystal structure of the LRRK2 ROC domain in complex with GDP-Mg2+ at 2.0-Å resolution. The structure displays a dimeric fold generated by extensive domain-swapping, resulting in a pair of active sites constructed with essential functional groups contributed from both monomers. Two PD-associated pathogenic residues, R1441 and I1371, are located at the interface of two monomers and provide exquisite interactions to stabilize the ROC dimer. The structure demonstrates that loss of stabilizing forces in the ROC dimer is likely related to decreased GTPase activity resulting from mutations at these sites. Our data suggest that the ROC domain may regulate LRRK2 kinase activity as a dimer, possibly via the C-terminal of ROC (COR) domain as a molecular hinge. The structure of the LRRK2 ROC domain also represents a signature from a previously undescribed class of GTPases from complex proteins and results may provide a unique molecular target for therapeutics in PD.

The role of incentives for sustainable implementation of marine protected areas: an example from Tanzania

Although Marine Protected Areas (MPAs) are an increasingly popular policy tool for protecting marine stocks and biodiversity, they pose high costs for small-scale fisherfolk in poor countries. With Tanzania’s Mnazi Bay Ruvuma Estuary Marine Park as an example, we develop a spatial economic decision-modelling framework as a lens to examine fishers’ reactions to incentives created by an MPA. We argue that MPAs in poor countries can only contribute to sustainability if management induces changes in incentives to fish through a combination of enforcement (‘sticks’) and livelihood projects (‘carrots’). We emphasise practical implementation issues and implications for fostering marine ecosystem sustainability.

A microblock ionomer in proton exchange membrane electrolysis for the production of high purity hydrogen

Proton exchange membranes (PEM’s) are currently under investigation for membrane water electrolysis (PEMWE) to deliver efficient production of the high purity hydrogen needed to supply emerging clean-energy technologies such as hydrogen fuel cells. The microblock aromatic ionomer described in this work achieves high mechanical strength in an aqueous environment as a result of its designed, biphasic morphology and displays many of the qualities required in a PEM. The new ionomer membrane thus shows good proton conductivity (63 mS cm−1 at 80 °C and 100% RH), while retaining mechanical integrity under high temperature, hydrated conditions. Testing in electrolysis has shown good energy efficiency (1.67 V at 1 A cm−2 and 80 °C, corresponding to 4 kWh/Nm3 of H2), making this ionomer a potential candidate for commercial application in PEMWE.

Power transfer in velocity-vortex acceleration

A theoretical model is presented of an electron acceleration-as-oscillator method derived from the work of Joseph Larmor unified with J. Clerk Maxwell’s theory of vorticity for the displacement of radiation into free-space at an antenna interface.

A method to assess individual research outputs

We present here a straightforward method which can be used to obtain a quantitative indication of an individual research output for an academic. Different versions, selections and options are presented to enable a user to easily calculate values both for stand-alone papers and overall for the collection of outputs for a person. The procedure is particularly useful as a metric to give a quantitative indication of the research output of a person over a time window. Examples are included to show how the method works in practice and how it compares to alternative techniques.

The impact of social and relational contexts on innovation transfer in foreign subsidiaries

It is widely acknowledged that innovation is one of the pillars of multinational enterprises (MNEs) and that technological knowledge from different host locations is a key factor to the MNEs’ competitive advantages development. Concerning these assumptions, in this paper we aim to understand how the social and the relational contexts affect the conventional and reverse transfer of innovation from MNEs’ subsidiaries hosted in emerging markets. We analyzed the social context through the institutional profile (CIP) level and the relational context through trust and integration levels utilizing a survey sent to 172 foreign subsidiaries located in Brazil, as well as secondary data. Through an ordinary least squares regression (OLS) analysis we found that the relational context affects the conventional and reverse innovation transfer in subsidiaries hosted in emerging markets. We however did not find support for the social context effect.

Narratives of grassroots innovations: a comparison of voluntary simplicity and the transition movement in Italy

Grassroots innovations (GI) are promising examples of deliberate transformation of socio-technical systems towards resilience and sustainability. However, evidence is needed on the factors that limit or enable their success. This paper set out to study how GI use narratives to empower innovation in the face of incumbent socio-technical regimes. Institutional documents were comparatively analyzed to assess how the narratives influence the structure, form of action and external interactions of two Italian grassroots networks, Bilanci di Giustizia and Transition Network Italy. The paper finds an internal consistency between narratives and strategies for each of the two networks. The paper also highlights core similarities, but also significant differences in the ethical basis of the two narratives, and in the organizations and strategies. Such differences determine different forms of innovation empowerment and expose the niche to different potentials to transform incumbent regimes, or to the risk of being co-opted by them.

Classification in e-procurement

Three coupled knowledge transfer partnerships used pattern recognition techniques to produce an e-procurement system which, the National Audit Office reports, could save the National Health Service £500 m per annum. An extension to the system, GreenInsight, allows the environmental impact of procurements to be assessed and savings made. Both systems require suitable products to be discovered and equivalent products recognised, for which classification is a key component. This paper describes the innovative work done for product classification, feature selection and reducing the impact of mislabelled data.

Body-centric modelling, identification, and acceleration tracking control of a quadrotor UAV

This paper presents the mathematical development of a body-centric nonlinear dynamic model of a quadrotor UAV that is suitable for the development of biologically inspired navigation strategies. Analytical approximations are used to find an initial guess of the parameters of the nonlinear model, then parameter estimation methods are used to refine the model parameters using the data obtained from onboard sensors during flight. Due to the unstable nature of the quadrotor model, the identification process is performed with the system in closed-loop control of attitude angles. The obtained model parameters are validated using real unseen experimental data. Based on the identified model, a Linear-Quadratic (LQ) optimal tracker is designed to stabilize the quadrotor and facilitate its translational control by tracking body accelerations. The LQ tracker is tested on an experimental quadrotor UAV and the obtained results are a further means to validate the quality of the estimated model. The unique formulation of the control problem in the body frame makes the controller better suited for bio-inspired navigation and guidance strategies than conventional attitude or position based control systems that can be found in the existing literature.

Bond graph models of DC-DC converters operating in both CCM and DCM

In this paper, Bond Graphs are employed to develop a novel mathematical model of conventional switched-mode DC-DC converters valid for both continuous and discontinuous conduction modes. A unique causality bond graph model of hybrid models is suggested with the operation of the switch and the diode to be represented by a Modulated Transformer with a binary input and a resistor with fixed conductance causality. The operation of the diode is controlled using an if-then function within the model. The extracted hybrid model is implemented on a Boost and Buck converter with their operations to change from CCM to DCM and to return to CCM. The vector fields of the models show validity in a wide operation area and comparison with the simulation of the converters using PSPICE reveals high accuracy of the proposed model, with the Normalised Root Means Square Error and the Maximum Absolute Error remaining adequately low. The model is also experimentally tested on a Buck topology.

Global scale transcriptome analysis of Arabidopsis embryogenesis in vitro

Background Somatic embryogenesis (SE) in plants is a process by which embryos are generated directly from somatic cells, rather than from the fused products of male and female gametes. Despite the detailed expression analysis of several somatic-to-embryonic marker genes, a comprehensive understanding of SE at a molecular level is still lacking. The present study was designed to generate high resolution transcriptome datasets for early SE providing the way for future research to understand the underlying molecular mechanisms that regulate this process. We sequenced Arabidopsis thaliana somatic embryos collected from three distinct developmental time-points (5, 10 and 15 d after in vitro culture) using the Illumina HiSeq 2000 platform. Results This study yielded a total of 426,001,826 sequence reads mapped to 26,520 genes in the A. thaliana reference genome. Analysis of embryonic cultures after 5 and 10 d showed differential expression of 1,195 genes; these included 778 genes that were more highly expressed after 5 d as compared to 10 d. Moreover, 1,718 genes were differentially expressed in embryonic cultures between 10 and 15 d. Our data also showed at least eight different expression patterns during early SE; the majority of genes are transcriptionally more active in embryos after 5 d. Comparison of transcriptomes derived from somatic embryos and leaf tissues revealed that at least 4,951 genes are transcriptionally more active in embryos than in the leaf; increased expression of genes involved in DNA cytosine methylation and histone deacetylation were noted in embryogenic tissues. In silico expression analysis based on microarray data found that approximately 5% of these genes are transcriptionally more active in somatic embryos than in actively dividing callus and non-dividing leaf tissues. Moreover, this identified 49 genes expressed at a higher level in somatic embryos than in other tissues. This included several genes with unknown function, as well as others related to oxidative and osmotic stress, and auxin signalling. Conclusions The transcriptome information provided here will form the foundation for future research on genetic and epigenetic control of plant embryogenesis at a molecular level. In follow-up studies, these data could be used to construct a regulatory network for SE; the genes more highly expressed in somatic embryos than in vegetative tissues can be considered as potential candidates to validate these networks.

Influence of inherent structure shear stress of supercooled liquids on their shear moduli

Configurations of supercooled liquids residing in their local potential minimum (i.e. in their inherent structure, IS) were found to support a non-zero shear stress. This IS stress was attributed to the constraint to the energy minimization imposed by boundary conditions, which keep size and shape of the simulation cell fixed. In this paper we further investigate the influence of these boundary conditions on the IS stress. We investigate its importance for the computation of the low frequency shear modulus of a glass obtaining a consistent picture for the low- and high frequency shear moduli over the full temperature range. Hence, we find that the IS stress corresponds to a non-thermal contribution to the fluctuation term in the Born-Green expression. This leads to an unphysical divergence of the moduli in the low temperature limit if no proper correction for this term is applied. Furthermore, we clarify the IS stress dependence on the system size and put its origin on a more formal basis.

Output sustainability to exogenous and endogenous shocks: evidence from emerging economies

This paper studies the impact of exogenous and endogenous shocks (exogenous shock is used interchangeably with external shock; endogenous shock is used interchangeably with domestic shock) on output fluctuations in post-communist countries during the 2000s. The first part presents the analytical framework and formulates a research hypothesis. The second part presents vector autoregressive estimation and analysis model proposed by Pesaran (2004) and Pesaran and Smith (2006) that relates bank real lending, the cyclical component of output and spreads and accounts for cross-sectional dependence (CD) across the countries. Impulse response functions show that exogenous positive shock lead to a drop in output sustainability for 9 over 12 Central Eastern European countries and Russia, when the endogenous shock is mild and ambiguous. Moreover, the effect of exogenous shock is more significant during the crises. Variance decompositions show that exogenous shock in the aftermath of crisis had a substantial impact on economic activity of emerging economies.

Experiential learning from entrepreneurial failure

This paper examines the phenomenon of 'entrepreneurial failure' from a UK regionally-based qualitative study, being that of explanations for failure provided by entrepreneurial CEOs. This paper contends that there are valuable lessons to be learned, from explanations provided of failure, that may reduce the very high recorded mortality rates of entrepreneurial businesses, in particular that of nascent entrepreneurs. Our intention is to make nascent entrepreneurs and their advisors more aware of the consequences of the likely personal risks they will be assuming, especially before they embark on their new business ventures. This paper focuses strongly on entrepreneurial 'personality characteristics' which can detrimentally influence the quality of decision-making. We provide data of some 'experiential learning from failure' from our case studies, that were compiled from interviews with the former directors, following their completion of the questionnaire survey. We describe 'failed entrepreneurs' who have successfully restarted their businesses as 'phoenix' entrepreneurs.