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When assessing the benefits and risks of transgenic crops, one consideration is their relative effects on non-target arthropod (NTA) abundance and functions within agroecosystems. Several laboratory and field trials have been conducted in Spain since the late 1990s to assess this issue. A consideration in the design of field trials is whether it is necessary to sample most NTAs living in the crop or only representative taxa that perform main ecological functions and have a good capacity to detect small changes in their abundance. Small changes in the field abundance of an effective representative taxon should be detectable using standard experimental protocols. The ability of a species to reveal differences across treatments may be analysed by examining the detectable treatment effects for surveyed non-target organisms. Analysis of data from several NTAs recorded in 14 field trials conducted over 10 years using complete block designs allowed us to select a number of representative taxa capable of detecting changes in the density or activity of arthropod herbivores, predators, parasitoids and decomposers in transgenic and non-transgenic maize varieties. The most suitable NTA as representative taxa (with detectable treatment effects below 50%) included leafhoppers among arthropod herbivores, Orius spp., Araneae, and Carabidae among predators, chalcidids, particularly the family Mymaridae, among parasitoids and Chloropidae as decomposer. Details of sampling techniques for each sampled taxa and their advantages and disadvantages are discussed. It is concluded that abundance of taxa is the most influential factor determining their capacity to detect changes caused by genetically modified varieties.
We report on the long term X-ray monitoring with Swift, RXTE, Suzaku, Chandra, and XMM-Newton of the outburst of the newly discovered magnetar Swift J1822.3–1606 (SGR 1822-1606), from the first observations soon after the detection of the short X-ray bursts which led to its discovery (July 2011), through the first stages of its outburst decay (April 2012). Our X-ray timing analysis finds the source rotating with a period of P = 8.43772016(2) s and a period derivative Ṗ = 8.3(2) × 10−14 ss−1, which entails an inferred dipolar surface magnetic field of B ≃ 2.7 × 1013 G at the equator. This measurement makes Swift J1822.3–1606 the second lowest magnetic field magnetar (after SGR 0418+5729; Rea et al. 2010). Following the flux and spectral evolution from the beginning of the outburst, we find that the flux decreased by about an order of magnitude, with a subtle softening of the spectrum, both typical of the outburst decay of magnetars. By modeling the secular thermal evolution of Swift J1822.3–1606, we find that the observed timing properties of the source, as well as its quiescent X-ray luminosity, can be reproduced if it was born with a poloidal and crustal toroidal fields of Bp ~ 1.5 × 1014 G and Btor ~ 7 × 1014 G, respectively, and if its current age is ~550 kyr (Rea et al. 2012).
Tantalum oxide (Ta2O5) films were deposited onto p-type silicon substrates using reactive DC magnetron sputtering, and then annealed for one hour in a dry air ambient at temperatures of 730°C, 780°C, and 830°C. Annealing was shown to reduce stress from the as-deposited sample, and resulted in a compressive stress state for samples annealed at 730°C and a tensile stress state for the other samples. Hardness values were approximately 8 GPa, with the exception of the sample annealed at 780°C that demonstrated a hardness of 13 GPa. Leakage current generally decreased with annealing, especially at the lower temperatures. Electrical breakdown was observed for as-deposited and the 830°C annealed films. Resistivities of the films ranged from 6.5 × 109 to 6.1 × 1012 ω-cm, with the film annealed at 830°C being the most conductive. Annealing also led to an increase in dielectric constant. Dielectric constants varied from 9.3 for the as-deposited to greater than 30 for the 780°C and 830°C annealed sample. Annealing resulted in crystalline films that were close to stoichiometric.
The purpose of this article is to present the modeling routes for the chemical vapor deposition process with a special emphasis to mass transport models with near local thermochemical equilibrium imposed in the gas-phase and at the deposition surface. The theoretical problems arising from the linking of the two selected approaches, thermodynamics and mass transport, are shown and a solution procedure is proposed. As an illustration, selected results of thermodynamic and mass transport analysis and of the coupled approach showed that, for the deposition of Si1-x Gex solid solution at 1300 K (system Si-Ge-Cl-H-Ar), the thermodynamic heterogeneous stability of the reactive gases and the thermal diffusion led to the germanium depletion of the deposit.
The guidelines for designing a conductive, amorphous material, capable of thermodynamic equilibrium with copper, are defined using readily available thermodynamic information. The tradeoff between desired properties – equilibrium at the interfaces, amorphous microstructure, and electronic conductivity – are described, along with trends in relevant binary systems that result in these properties. These guidelines defined systems for experimental study, for which preliminary results are presented.
This paper shows the potentialities of merging the MEMS and micromachining with SiGe technologies in order to speed up the performances of next generation of front end in term of flexibility, reconfigurability and adaptability. MEMS technologies are presented based on Benzo-Cyclo-Butene (BCB) materials and Bulk Acoustic Wave (BAW) materials. Special attention is paid to ensure a full compatibility between IC and MEMS. We have shown that very innovative functions could be considered by using this MEMSIC concept.
In the current cosmological scenario, part of the linearly polarized
emission of the CMB is expected to be rotational (B-modes). This
component is due to tensor perturbations of the metric produced by
primordial gravitational waves, which are generated a split-second after the
Big Bang. The signal expected is of the order of ≲ 0.1 μK, well below the non-rotational component of the polarization
signal (E-modes), and beyond the sensitivity of present generation
instruments. New, more sensitive instruments are developed in
several labs, with the goal to measure the B-modes. Control of
systematics and foregrounds will be the key to make the results of
these experiments believable. In this paper we shortly outline
BRAIN, a bolometric interferometer devoted to B-modes research,
and its pathfinder experiment, devoted to test the Dome-C site.
The design of multifunctional upper limb prosthetics has been investigated in recent years. Several areas or research need to be developed for successful implementation of dextrous upper limb prosthesis, in particular better EMG interfaces for implementing command languages.
This article introduces a novel three-bit EMG command language concept as a user interface for the multifunctional MANUS prosthesis prototype. Following the global approach proposed by MANUS, a training process and the supporting Virtual Reality training software are also presented. The last section describes the evaluation process and the results.
The design of multifunctional upper limb prosthetics has been investigated in recent years. In 1998, the MANUS consortium was set up on the basis of multidisciplinary skills of the partners in order to provide a global approach to the problem of upper limb prosthetics. In the framework of this approach, the consortium addressed the development of appropriate hand mechanics, the analysis and implementation of control electronics, the development of advanced control strategies and the implementation of broad band command interfaces based on EMG.
As a result, the prototype of a multifunctional prosthesis was developed, integrated and clinically evaluated. This paper describes the objectives, technological approach and results of the MANUS prosthesis prototype.
To identify risk factors associated with an unexpected outbreak of pyrogenic reactions (PR) following intravenous gentamicin.
We conducted two cohort studies. PRs were defined as chills, rigors, or shaking within 3 hours after initiating the gentamicin infusion during the preepidemic (December 1, 1997-January 15,1998) or epidemic (May 1-June 15,1998) periods. We tested gentamicin vials for endotoxin using the limulus amebocyte lysate assay.
Inpatient services of a large community hospital in Los Angeles, California.
During the epidemic period, 22 (15%) of 152 patients developed documented PRs following intravenous gentamicin. PRs were more likely among patients receiving single daily dosing (SDD) than multiple daily dosing gentamicin (20/73 [27%] vs 2/79 [3%]; relative risk, 10.8; 95% confidence interval, 2.644.7). Laboratory analysis of gentamicin vials found endotoxin levels that were higher among Fujisawa-brand gentamicin (implicated brand) than gentamicin used after the outbreak terminated (non-implicated brand). Although endotoxin levels in the vials did not exceed US Pharmacopeia limits (1.7 endotoxin units/mg gentamicin), the use of SDD gentamicin may place patients at greater risk of receiving doses of endotoxin above the threshold for PRs in humans.
Reassessment of the acceptable amounts of endotoxin in gentamicin and other parenteral products should be considered when dosing intervals used in clinical practice change.
The three-dimensional (3D) structure of fructan
biosynthetic enzymes is still unknown. Here, we have explored
folding similarities between reported microbial and plant
enzymes that catalyze transfructosylation reactions. A
sequence-structure compatibility search using TOPITS, SDP,
3D-PSSM, and SAM-T98 programs identified a β-propeller
fold with scores above the confidence threshold that indicate
a structurally conserved catalytic domain in fructosyltransferases
(FTFs) of diverse origin and substrate specificity. The
predicted fold appeared related to that of neuraminidase
and sialidase, of glycoside hydrolase families 33 and 34,
respectively. The most reliable structural model was obtained
using the crystal structure of neuraminidase (Protein Data
Bank file: 5nn9) as template, and it is consistent with
the location of previously identified functional residues
of bacterial levansucrases (Batista et al., 1999; Song &
Jacques, 1999). The sequence–sequence analysis presented here
reinforces the recent inclusion of fungal and plant FTFs into glycoside
hydrolase family 32, and suggests a modified sequence pattern
for this family.
During the last two decades a large amount of effort and attention has been
paid to the problem of designing and controlling dextrous robotics hands. The possible application background ranges from telerobotics to upper limb prosthetics, while actual industrial developments are mainly limited to specific grippers and tools. Classical problems related to dextrous hand design are kinematics of multifingered hands, development of proper actuation technologies and redundant tendinous systems for transmission. As far as
hand control is concerned, grasp preshaping, planning and synthesis are of major concern, while sensor guided hand operation is still a matter of research. The present work reviews the above mentioned hand design and control issues trying to throw some light on the Babel-like confusion encountered when looking at present literature on dextrous hand design and specially control. Most actuation and transmission technologies, as well as control approaches, are studied and classified.
Ferrofluids are colloidal solutions of iron oxide magnetic nanoparticles
in either a
polar or no polar liquid. We present here two biological applications using maghemite
(γFe2O3) ferrofluids: magnetic cell sorting and magnetocytolysis.
The first application employs magnetic particles binding a biological effector, which
is capable to recognize the target cells specifically. These cells become magnetic and can
be sorted in a gradient of magnetic field. We describe first the various steps of the
synthesis of a biocompatible ferrofluid and the grafting an effector protein onto the
particles. We then describe the use of particles carrying annexin V in the separation and
quantification of damaged erythrocytes in blood samples. This very sensitive technique can
be used to follow the erythrocytes ageing of normal blood samples during their storage
under blood bank conditions or to detect the membrane modifications that are associated
with some pathologies such as malaria or Alzheimer's disease.
The dependence of the magnetic susceptibility versus the frequency is a way to
transform magnetic energy into thermal energy. Magnetocytolysis is the destruction of
cells, carrying magnetic particles, through the action of an alternating magnetic field (about
1 MHz). We present here preliminary experiments with macrophages, which demonstrate
the method's feasibility and the formation of the non-specific interactions between the cells
and the magnetic particles.
This study was performed to examine the main characteristics of the French Romulus twin population: zygosity, chorionicity, sex, term and birthweight. A sample of 104 pairs of twins was distinguished by zygosity, chorionicity and sex, and divided into concordant and discordant birthweight groups. Fifty-three % (n = 55) of the fetus pairs studied were born at “ideal term” (35-38 weeks), and 25% (n = 26) were delivered at “preterm” (28-34 weeks). The very preterm (< 28 weeks), and “postterm” (> 38 weeks) represented altogether 22% (n = 23) of the sample. Of the 104 twin pairs, 68% (n = 71) differ by less than 15% in birthweight, and 32% (n = 33) have a birthweight difference higher than 15%. In dizygotic (DZ) pairs females had more tendency to be in the discordant group (p = 0.01) while in monochorionic-monozygotic (MC-MZ) pairs males were more discordant (p = 0.07). We found a significant interaction between sex and zygosity type (p = 0.02). Males had a birthweight difference significantly weaker than that of females in dichorionic-monozygotic (DC-MZ) and DZ twins whereas it was higher than that of females in MC-MZ twins. There were no MZ twin pairs with DC placentation over than 15% birthweight difference. Log linear analysis demonstrated a three-way interaction (p < 0.05) between term type, zygosity type and hypotrophy. Our data indicate that in the group of twins born between 35 and 38 weeks' gestation the crucial question still remains unsettled on how term and birhweight are related to zygotism and/or chorionicity.
Parents of a sample of 76 same sexed pairs of twins aged 3 to 9 months completed a mailed similarity questionnaire. It included the Bonnelykke et al.'s questionnaire and a four anthropological variable scale. To improve each of these two methods, three other combined methods were carried out and results were compared with the biological zygosity diagnosis. The Bonnelykke et al.'s classification combined with anthropological scale (method 4) gave only 1.2% misclassified in the whole sample. It is concluded that zygosity diagnosis using this type of procedure to distinguish MZ and DZ pairs would be important not only for epidemiological study but also for pediatricians and parents.
A case is reported of a transfusion syndrome in a triplet pregnancy with intrauterine death of two of the fetuses. This is an exceptional occurrence in a triplet pregnancy and raises the problem of the management of multiple pregnancies associated with the death of one or more of the fetuses. The problem of the method of delivery and the complications arising in triplet dizygotic pregnancies is discussed.