CYPERMETHRIN NON-TARGET IMPACT ON SOIL MICROBIAL COMMUNITIES: LABORATORY ARTIFICIAL INCUBATION EXPERIMENT

Intensive and excessive use of pesticides is a real pollution issue in agricultural lands. There is little knowledge on how these could change soil microbiota health status which are strongly involved in important soil functions. The objective of the present study was to assess under laboratory conditions if use of a common pyrethroid pesticide, cypermethrin, will change soil microbiota structure and abundance. Cypermethrin exposure dose and removal in time were accounted also. Its amount was quantified on GC-ECD while information about microbiota, expressed as PLFA, were acquired on GC-FID. Incubation period after artificial contaminations between 7 – 288 gkg-1 was set at 45 days, time during samples were picked up from incubation containers for chemical analysis. Experiment revealed that during the first ten days of exposure experiment, cypermethrin amount in soil decreased almost with half. It was removed with 68.8 – 43.3 %, depending positively by the exposure dose, thus it increased once that exposure dose decreased. The calculated half-life values under our experimental conditions vary between 4.59 - 10.54 days, depending by exposure dose. Compared with control soil gram-negative bacteria community was enhanced under cypermethrin exposure up to day 45 around 5.4 – 20.3 %, although the control has shown a slightly decreases from day 10 and 45 day. Fungal population decreased also between exposure time, as well exposure dose. After 10 days of incubation they weren’t be present in samples. Similar was obtained after measurement of anaerobe bacteria. Considering our obtained experimental data, we could consider that cypermethrin have the potential to change the soil equilibrium once that it changes both the structure as well the abundance of soil microbiota

RHIZOSPHERE MICROBIOTA PROFILE CHANGES WITH DIFFERENT GENETIC TYPES OF TOMATO SPECIES

Use of improved seeds (hybrids, transgenic, etc.) in agriculture is a common practice in our days. Resulted plants could improve crop yield or to develop in less adequate geoclimatic conditions, responding those to challenges raised by global change. However, at now there are limited information on potential impact of such plants on soil properties and microbiota. Considering that microbiota are key mediators of soil functions and ecosystem processes it is important to fulfil such gaps. The objective of this study was to identify if different genetic varieties of Cherry tomato (Solanum lycopersicum), grown in same conditions, could influence root exudates (mainly carbohydrates) and rhizosphere microbiota profile. Randomized complete block rhizo-box experiment was performed with identic soil under similar growing conditions of genetic varieties Cherry tomatoes. PLFA and carbohydrates were analysed on GC-FID. In soil where tomatoes were grown the total PLFA amount was approximately two times higher compared with that detected from control (669.1 nmolg-1), which means that tomato root rhizosphere and exudates could influence soil microbiota. The average value of total PLFA for heirloom varieties was 1575.5 nmolg-1 while for hybrid varieties was 1269.4 nmolg-1. ANOVA test revealed significant differences between genetic type varieties of Cherry tomato (Solanum lycopersicum) rhizosphere microbiota community structure. Gram-positive, gram-negative bacteria and fungi abundance decreased in hybrid Cherry tomato varieties rhizosphere soils. Decreases in microbial and fungi community abundance may be related with decrease in carbohydrates content following with grown of different genetic hybrid varieties of Cherry tomato where some species exudates are reduced in essential carbohydrates content

Adaptation and learning over networks for nonlinear system modeling

In this chapter, we analyze nonlinear filtering problems in distributed environments, e.g., sensor networks or peer-to-peer protocols. In these scenarios, the agents in the environment receive measurements in a streaming fashion, and they are required to estimate a common (nonlinear) model by alternating local computations and communications with their neighbors. We focus on the important distinction between single-task problems, where the underlying model is common to all agents, and multitask problems, where each agent might converge to a different model due to, e.g., spatial dependencies or other factors. Currently, most of the literature on distributed learning in the nonlinear case has focused on the single-task case, which may be a strong limitation in real-world scenarios. After introducing the problem and reviewing the existing approaches, we describe a simple kernel-based algorithm tailored for the multitask case. We evaluate the proposal on a simulated benchmark task, and we conclude by detailing currently open problems and lines of research.Comment: To be published as a chapter in `Adaptive Learning Methods for Nonlinear System Modeling', Elsevier Publishing, Eds. D. Comminiello and J.C. Principe (2018

Surface state engineering of molecule-molecule interactions

Engineering the electronic structure of organics through interface manipulation, particularly the interface dipole and the barriers to charge carrier injection, is of essential importance to improved organic devices. This requires the meticulous fabrication of desired organic structures by precisely controlling the interactions between molecules. The well-known principles of organic coordination chemistry cannot be applied without proper consideration of extra molecular hybridization, charge transer and dipole formation at the interfaces. Here we identify the interplay between energy level alignment, charge transfer, surface dipole and charge pillow effect and show how these effects collectively determine the net force between adsorbed porphyrin 2H-TPP on Cu(111). We show that the forces between supported porphyrins can be altered by controlling the amount of charge transferred across the interface accurately through the relative alignment of molecular electronic levels with respect to the Shockley surface state of the metal substrate, and hence govern the self-assembly of the molecules

Studying the Underlying Event in Drell-Yan and High Transverse Momentum Jet Production at the Tevatron

We study the underlying event in proton-antiproton collisions by examining the behavior of charged particles (transverse momentum pT > 0.5 GeV/c, pseudorapidity |\eta| < 1) produced in association with large transverse momentum jets (~2.2 fb-1) or with Drell-Yan lepton-pairs (~2.7 fb-1) in the Z-boson mass region (70 < M(pair) < 110 GeV/c2) as measured by CDF at 1.96 TeV center-of-mass energy. We use the direction of the lepton-pair (in Drell-Yan production) or the leading jet (in high-pT jet production) in each event to define three regions of \eta-\phi space; toward, away, and transverse, where \phi is the azimuthal scattering angle. For Drell-Yan production (excluding the leptons) both the toward and transverse regions are very sensitive to the underlying event. In high-pT jet production the transverse region is very sensitive to the underlying event and is separated into a MAX and MIN transverse region, which helps separate the hard component (initial and final-state radiation) from the beam-beam remnant and multiple parton interaction components of the scattering. The data are corrected to the particle level to remove detector effects and are then compared with several QCD Monte-Carlo models. The goal of this analysis is to provide data that can be used to test and improve the QCD Monte-Carlo models of the underlying event that are used to simulate hadron-hadron collisions.Comment: Submitted to Phys.Rev.

Observation of Exclusive Gamma Gamma Production in p pbar Collisions at sqrt{s}=1.96 TeV

We have observed exclusive \gamma\gamma production in proton-antiproton collisions at \sqrt{s}=1.96 TeV, using data from 1.11 \pm 0.07 fb^{-1} integrated luminosity taken by the Run II Collider Detector at Fermilab. We selected events with two electromagnetic showers, each with transverse energy E_T > 2.5 GeV and pseudorapidity |\eta| < 1.0, with no other particles detected in -7.4 < \eta < +7.4. The two showers have similar E_T and azimuthal angle separation \Delta\phi \sim \pi; 34 events have two charged particle tracks, consistent with the QED process p \bar{p} to p + e^+e^- + \bar{p} by two-photon exchange, while 43 events have no charged tracks. The number of these events that are exclusive \pi^0\pi^0 is consistent with zero and is < 15 at 95% C.L. The cross section for p\bar{p} to p+\gamma\gamma+\bar{p} with |\eta(\gamma)| < 1.0 and E_T(\gamma) > 2.5$ GeV is 2.48^{+0.40}_{-0.35}(stat)^{+0.40}_{-0.51}(syst) pb.Comment: 7 pages, 4 figure

Combined search for the standard model Higgs boson decaying to a bb pair using the full CDF data set

We combine the results of searches for the standard model Higgs boson based on the full CDF Run II data set obtained from sqrt(s) = 1.96 TeV p-pbar collisions at the Fermilab Tevatron corresponding to an integrated luminosity of 9.45/fb. The searches are conducted for Higgs bosons that are produced in association with a W or Z boson, have masses in the range 90-150 GeV/c^2, and decay into bb pairs. An excess of data is present that is inconsistent with the background prediction at the level of 2.5 standard deviations (the most significant local excess is 2.7 standard deviations).Comment: To be published in Phys. Rev. Lett (v2 contains minor updates based on comments from PRL