Towards the biocontrol of bindweeds with a mycoherbicide

Within the framework of the European COST Action 816, afive-year collaboration between scientists from five Europeancountries has made an important contribution to biologicalcontrol of field and hedge bindweeds (Convolvulus arvensis andCalystegia sepium, respectively). A fungus Stagonosporaconvolvuli strain LA39, able to infect both field and hedgebindweed, was found in the UK and its biocontrol efficacyimproved by optimising mass production, formulation and storagetechniques. This fungus controlled bindweeds in both a cemeteryand in maize crops. Its use fits best in an integrated pestmanagement system where a green cover controls most of the weedsexcept the bindweeds. DNA marker analyses indicate that thefungus reproduces sexually, which could be used to furtherimprove this mycoherbicide. In addition, the insect Melanagromyzaalbocilia, which itself exhibits biocontrol potential againstbindweeds, may be used in combination with LA39 to improve theability of the fungus to penetrate the stem of bindweeds.Overall, the results suggest that S. convolvuli LA39 haspromising potential as a bioherbicide for control of field andhedge bindwee

Nonequilibrium thermodynamics of interacting tunneling transport: variational grand potential, density-functional formulation, and nature of steady-state forces

The standard formulation of tunneling transport rests on an open-boundary modeling. There, conserving approximations to nonequilibrium Green function or quantum-statistical mechanics provide consistent but computational costly approaches; alternatively, use of density-dependent ballistic-transport calculations [e.g., Phys. Rev. B 52, 5335 (1995)], here denoted `DBT', provide computationally efficient (approximate) atomistic characterizations of the electron behavior but has until now lacked a formal justification. This paper presents an exact, variational nonequilibrium thermodynamic theory for fully interacting tunneling and provides a rigorous foundation for frozen-nuclei DBT calculations as a lowest order approximation to an exact nonequilibrium thermodynamics density functional evaluation. The theory starts from the complete electron nonequilibrium quantum statistical mechanics and I identify the operator for the nonequilibrium Gibbs free energy. I demonstrate a minimal property of a functional for the nonequilibrium thermodynamic grand potential which thus uniquely identifies the solution as the exact nonequilibrium density matrix. I also show that a uniqueness-of-density proof from a closely related study [Phys. Rev. B 78, 165109 (2008)] makes it possible to provide a single-particle formulation based on universal electron-density functionals. I illustrate a formal evaluation of the thermodynamics grand potential value which is closely related to the variation in scattering phase shifts and hence to Friedel density oscillations. This paper also discusses the difference between the here-presented exact thermodynamics forces and the often-used electrostatic forces. Finally the paper documents an inherent adiabatic nature of the thermodynamics forces and observes that these are suited for a nonequilibrium implementation of the Born-Oppenheimer approximation.Comment: 37 pages, 3 Figure

The insect-focused classification of fruit syndromes in tropical rainforests: an inter-continental comparison

We propose a new classification of rainforest plants into eight fruit syndromes, based on fruit morphology and other traits relevant to fruit-feeding insects. This classification is compared with other systems based on plant morphology or traits relevant to vertebrate fruit dispersers. Our syndromes are based on fruits sampled from 1,192 plant species at three Forest Global Earth Observatory plots: Barro Colorado Island (Panama), Khao Chong (Thailand) and Wanang (Papua New Guinea). The three plots differed widely in fruit syndrome composition. Plant species with fleshy, indehiscent fruits containing multiple seeds were important at all three sites. However, in Panama a high proportion of species had dry fruits, while in New Guinea and Thailand, species with fleshy drupes and thin mesocarps were dominant. Species with dry, winged seeds that do not develop as capsules were important in Thailand, reflecting the local importance of Dipterocarpaceae. These differences can also determine differences among frugivorous insect communities. Fruit syndromes and colours were phylogenetically flexible traits at the scale studied, as only three of the eight seed syndromes, and one of the 10 colours, showed significant phylogenetic clustering at either genus or family levels. Plant phylogeny was, however, the most important factor explaining differences in overall fruit syndrome composition among individual plant families or genera across the three study sites

Force plate monitoring of human hemodynamics

which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Background: Noninvasive recording of movements caused by the heartbeat and the blood circulation is known as ballistocardiography. Several studies have shown the capability of a force plate to detect cardiac activity in the human body. The aim of this paper is to present a new method based on differential geometry of curves to handle multivariate time series obtained by ballistocardiographic force plate measurements. Results: We show that the recoils of the body caused by cardiac motion and blood circulation provide a noninvasive method of displaying the motions of the heart muscle and the propagation of the pulse wave along the aorta and its branches. The results are compared with the data obtained invasively during a cardiac catheterization. We show that the described noninvasive method is able to determine the moment of a particular heart movement or the time when the pulse wave reaches certain morphological structure. Conclusions: Monitoring of heart movements and pulse wave propagation may be used e.g. to estimate the aortic pulse wave velocity, which is widely accepted as an index of aortic stiffness wit

Ab initio van der Waals interactions in simulations of water alter structure from mainly tetrahedral to high-density-like

The structure of liquid water at ambient conditions is studied in ab initio molecular dynamics simulations using van der Waals (vdW) density-functional theory, i.e. using the new exchange-correlation functionals optPBE-vdW and vdW-DF2. Inclusion of the more isotropic vdW interactions counteracts highly directional hydrogen-bonds, which are enhanced by standard functionals. This brings about a softening of the microscopic structure of water, as seen from the broadening of angular distribution functions and, in particular, from the much lower and broader first peak in the oxygen-oxygen pair-correlation function (PCF), indicating loss of structure in the outer solvation shells. In combination with softer non-local correlation terms, as in the new parameterization of vdW-DF, inclusion of vdW interactions is shown to shift the balance of resulting structures from open tetrahedral to more close-packed. The resulting O-O PCF shows some resemblance with experiment for high-density water (A. K. Soper and M. A. Ricci, Phys. Rev. Lett., 84:2881, 2000), but not directly with experiment for ambient water. However, an O-O PCF consisting of a linear combination of 70% from vdW-DF2 and 30% from experiment on low-density liquid water reproduces near-quantitatively the experimental O-O PCF for ambient water, indicating consistency with a two-liquid model with fluctuations between high- and low-density regions

A Glutamic Acid-Rich Protein Identified in Verticillium dahliae from an Insertional Mutagenesis Affects Microsclerotial Formation and Pathogenicity

Verticillium dahliae Kleb. is a phytopathogenic fungus that causes wilt disease in a wide range of crops, including cotton. The life cycle of V. dahliae includes three vegetative phases: parasitic, saprophytic and dormant. The dormant microsclerotia are the primary infectious propagules, which germinate when they are stimulated by root exudates. In this study, we report the first application of Agrobacterium tumefaciens-mediated transformation (ATMT) for construction of insertional mutants from a virulent defoliating isolate of V. dahliae (V592). Changes in morphology, especially a lack of melanized microsclerotia or pigmentation traits, were observed in mutants. Together with the established laboratory unimpaired root dip-inoculation approach, we found insertional mutants to be affected in their pathogenicities in cotton. One of the genes tagged in a pathogenicity mutant encoded a glutamic acid-rich protein (VdGARP1), which shared no significant similarity to any known annotated gene. The vdgarp1 mutant showed vigorous mycelium growth with a significant delay in melanized microsclerotial formation. The expression of VdGARP1 in the wild type V529 was organ-specific and differentially regulated by different stress agencies and conditions, in addition to being stimulated by cotton root extract in liquid culture medium. Under extreme infertile nutrient conditions, VdGARP1 was not necessary for melanized microsclerotial formation. Taken together, our data suggest that VdGARP1 plays an important role in sensing infertile nutrient conditions in infected cells to promote a transfer from saprophytic to dormant microsclerotia for long-term survival. Overall, our findings indicate that insertional mutagenesis by ATMT is a valuable tool for the genome-wide analysis of gene function and identification of pathogenicity genes in this important cotton pathogen

A Kir6.2 mutation causing severe functional effects in vitro produces neonatal diabetes without the expected neurological complications

AIMS/HYPOTHESIS: Heterozygous activating mutations in the pancreatic ATP-sensitive K+ channel cause permanent neonatal diabetes mellitus (PNDM). This results from a decrease in the ability of ATP to close the channel, which thereby suppresses insulin secretion. PNDM mutations that cause a severe reduction in ATP inhibition may produce additional symptoms such as developmental delay and epilepsy. We identified a heterozygous mutation (L164P) in the pore-forming (Kir6.2) subunit of the channel in three unrelated patients and examined its functional effects. METHODS: The patients (currently aged 2, 8 and 20 years) developed diabetes shortly after birth. The two younger patients attempted transfer to sulfonylurea therapy but were unsuccessful (up to 1.1 mg kg(-1) day(-1)). They remain insulin dependent. None of the patients displayed neurological symptoms. Functional properties of wild-type and mutant channels were examined by electrophysiology in Xenopus oocytes. RESULTS: Heterozygous (het) and homozygous L164P K(ATP) channels showed a marked reduction in channel inhibition by ATP. Consistent with its predicted location within the pore, L164P enhanced the channel open state, which explains the reduction in ATP sensitivity. HetL164P currents exhibited greatly increased whole-cell currents that were unaffected by sulfonylureas. This explains the inability of sulfonylureas to ameliorate the diabetes of affected patients. CONCLUSIONS/INTERPRETATION: Our results provide the first demonstration that mutations such as L164P, which produce a severe reduction in ATP sensitivity, do not inevitably cause developmental delay or neurological problems. However, the neonatal diabetes of these patients is unresponsive to sulfonylurea therapy. Functional analysis of PNDM mutations can predict the sulfonylurea response

Insights into the mechanism of nitrobenzene reduction to aniline over Pt catalyst and the significance of the adsorption of phenyl group on kinetics

This paper was accepted for publication in the journal Chemical Engineering Journal and the definitive published version is available at http://dx.doi.org/10.1016/j.cej.2016.02.066Aniline (C6H5NH2) plays a significant role in both industry and daily life, and can be synthesized via catalytic hydrogenation of nitrobenzene (C6H5NO2) over transition metals; however fundamental investigations on reaction mechanisms in the heterogeneous catalysis are still lacking. In this work, the nitrobenzene reduction reaction over the Pt(111) model catalyst was studied using density functional theory (DFT) with the inclusion of van der Waals interaction, for fundamentally understanding the mechanisms at atomic and molecular levels. It was found that the double H-induced dissociation of N-O bond was the preferential path for the activation of nitro group, having a much lower reaction barrier than that of the direct dissociation and single H-induced dissociation paths. The overall mechanisms have been identified as: C6H5NO2* → C6H5NOOH* → C6H5N(OH)2* → C6H5NOH* → C6H5NHOH* → C6H5NH* → C6H5NH2*. The overall barrier of the nitro group reduction was calculated to be 0.75 eV, which is much lower than that of the benzene reduction (1.08 eV). Our DFT data elucidates clearly the reason why the major product of nitrobenzene reduction reaction was aniline. Furthermore, the adsorption/desorption of phenyl group was found to have significant impacts on kinetic barriers. Generally, in the hydrogenation process (N-H or O-H bond association), the phenyl group preferred to adsorb on the surface; but in the dissociation process (N-O bond dissociation) it preferred to desorb transiently at the transition state and to adsorb again when the dissociation was completed. This study also provides a solid theoretical insight into the selective catalysis of the large aromatic compounds

Associations between DSM-IV diagnosis, psychiatric symptoms and morning cortisol levels in a community sample of adolescents

Purpose. Dysfunction of the hypothalamic-pituitary-adrenocortical axis (HPA-axis) is implicated in a variety of psychiatric and emotional disorders. In this study, we explore the association between HPA-axis functioning, as measured by morning cortisol, and common psychiatric disorders and symptoms among a community sample of adolescents. Method. Data from a cross-sectional school-based survey of 501 school pupils, aged 15, were used to establish the strength of association between salivary morning cortisol and both diagnosis of psychiatric disorders and a number of psychiatric symptoms, as measured via a computerised psychiatric interview. Analysis, conducted separately by gender, used multiple regressions, adjusting for relevant confounders. Results-á-áWith one exception (a positive association between conduct disorder symptoms and cortisol among females) there was no association between morning cortisol and psychiatric diagnosis or symptoms. However, there was a significant two-way interaction between gender and conduct symptoms, with females showing a positive and males a negative association between cortisol and conduct symptoms. A further three-way interaction showed that while the association between cortisol and conduct symptoms was negative among males with a few mood disorder symptoms, among females with many mood symptoms it was positive. Conclusions. Except in relation to conduct symptoms, dysregulation of morning cortisol levels seems unrelated to any psychiatric disorder or symptoms. However, the relationship between cortisol and conduct symptoms is moderated by both gender and mood symptoms. Findings are compatible with the recent work suggesting research should concentrate on the moderated associations between gender, internalising and externalising symptoms and cortisol, rather than any simple relationship