Characterisation of glyphosate uptake into grass species

2003 ◽  
Vol 54 (9) ◽  
pp. 877 ◽  
Author(s):  
Z. Q. Liu
Keyword(s):  
Leaf Surface ◽  
Current Knowledge ◽  
Grass Species ◽  
Droplet Spreading ◽  
Barnyard Grass ◽  
Spread Area ◽  
Per Se ◽  
High Level ◽  
Content Range ◽  
Determining Factor

The effect of surfactant ethylene oxide (EO) content, droplet spread area, and the active ingredient (a.i.) dose on the leaf surface on glyphosate uptake into 3 grass species (wheat, ryegrass, and barnyard grass) was investigated. It was found that glyphosate uptake into wheat was only moderately correlated (R2 = 0.66) with surfactant EO content (range 5–20 units per molecule). By contrast, a highly negative correlation (R2 = 0.98) was found between the uptake and the spread area of the treatment formulations on the leaf surface. The influence of droplet spreading on glyphosate uptake was further investigated using a super-spreading surfactant, Silwet L-77, and varying a.i. concentrations. It was demonstrated that the determining factor for glyphosate uptake into all 3 grass species was the a.i. dose (in μg/mm2) formed on the leaf surface after droplet spreading. Droplet spread area per se had only an indirect effect on the uptake through diluting the a.i. dose. In the presence of a non-spreading surfactant, Mon 0818, glyphosate uptake depended not only on the a.i. dose but also the surfactant dose on the leaf surface. In the absence of surfactants, high a.i. dose alone was not enough to ensure a high level uptake. The results are discussed in relation to the current knowledge on the interactions between surfactants and herbicide uptake.

scholarly journals Uptake of glyphosate into wheat surfactant interaction and mechanistic implications

2000 ◽  
Vol 53 ◽  
pp. 345-349 ◽  
Author(s):  
Z.Q. Liu ◽  
J.A. Zabkiewicz
Keyword(s):  
Leaf Surface ◽  
Threshold Dose ◽  
Droplet Spreading ◽  
Negative Effect ◽  
Spread Area ◽  
Per Se ◽  
High Level

Glyphosate uptake into wheat in the presence of Mon 0818 a tallow amine surfactant varied with both ai and surfactant dose on the leaf surface A high level of uptake (> 80 at 24 h) was recorded when the glyphosate dose was ge; 024 g/mm2 or when the Mon 0818 dose was ge; 048 g/mm2 When Mon 0818 and Silwet L77 were used together although droplet spread area and ai dose changed glyphosate uptake was still dose dependant and the threshold dose for 80 uptake (at 24 h) was still between 0203 g/mm2 This suggests that L77 has no negative effect per se on glyphosate uptake in the presence of Mon 0818 apart from affecting droplet spreading

North America

2018 ◽  
Author(s):  
Gregory Shushan
Keyword(s):  
Native American ◽  
North America ◽  
Reciprocal Relationship ◽  
Native American Religions ◽  
Widespread Acceptance ◽  
Revitalization Movements ◽  
Per Se ◽  
High Level ◽  
Near Death Experiences ◽  
Afterlife Beliefs

Dozens of Native American near-death experiences (NDEs) from the late sixteenth to early twentieth centuries are presented, ranging from across the continent. Many were accompanied by indigenous claims that they were the source for local afterlife beliefs. There were also many afterlife-related myths, and shamanic practices with NDE-like afterlife themes. In addition, numerous religious/cultural revitalization movements were claimed to have been grounded in the NDEs of their founders, and were conceptually related to the phenomenon. Near-death experiences could thus be an empowering force on a socio-cultural-political level in response to the threat of European dominance. There was a widespread acceptance and valorization of NDEs and related phenomena, and a high level of interest in the afterlife per se. Native American religions often showed a clear reciprocal relationship between shamanism, afterlife beliefs, and NDEs.

scholarly journals High-Intensity Focused Ultrasound Circular Cyclocoagulation in Glaucoma: A Step Forward for Cyclodestruction?

2017 ◽  
Vol 2017 ◽  
pp. 1-14 ◽  
Author(s):  
Rodolfo Mastropasqua ◽  
Vincenzo Fasanella ◽  
Alessandra Mastropasqua ◽  
Marco Ciancaglini ◽  
Luca Agnifili
Keyword(s):  
High Intensity ◽  
Ciliary Body ◽  
Focused Ultrasound ◽  
Current Knowledge ◽  
High Intensity Focused Ultrasound ◽  
High Rate ◽  
Dose Effect ◽  
Computer Assisted ◽  
Refractory Glaucoma ◽  
High Level

The ciliary body ablation is still considered as a last resort treatment to reduce the intraocular pressure (IOP) in uncontrolled glaucoma. Several ablation techniques have been proposed over the years, all presenting a high rate of complications, nonselectivity for the target organ, and unpredictable dose-effect relationship. These drawbacks limited the application of cyclodestructive procedures almost exclusively to refractory glaucoma. High-intensity focused ultrasound (HIFU), proposed in the early 1980s and later abandoned because of the complexity and side effects of the procedure, was recently reconsidered in a new approach to destroy the ciliary body. Ultrasound circular cyclocoagulation (UC3), by using miniaturized transducers embedded in a dedicated circular-shaped device, permits to selectively treat the ciliary body in a one-step, computer-assisted, and non-operator-dependent procedure. UC3 shows a high level of safety along with a predictable and sustained IOP reduction in patients with refractory glaucoma. Because of this, the indication of UC3 was recently extended also to naïve-to-surgery patients, thus reconsidering the role and timing of ciliary body ablation in the surgical management of glaucoma. This article provides a review of the most used cycloablative techniques with particular attention to UC3, summarizing the current knowledge about this procedure and future possible developments.

Consensus document on radiotherapy in patients with implantable pacemakers and cardioverter – defibrilators

2018 ◽  
Vol 2 (47) ◽  
pp. 27-31
Author(s):  
Lidia Chmielewska-Michalak ◽  
Ewelina Konstanty ◽  
Przemysław Mitkowski
Keyword(s):  
Current Knowledge ◽  
Clinical Status ◽  
Electronic Devices ◽  
Heart Rhythm ◽  
Complex Care ◽  
Consensus Document ◽  
Cardiac Implantable Electronic Devices ◽  
Number Of Patients ◽  
High Level ◽  
Emergency Mode

The number of patients with cardiac implantable electronic devices (CIED), who require oncological management including radiotherapy (RT) is still increasing. According to current knowledge the most frequent device dysfunction related to exposition to ionizing radiation is reprogramming to emergency mode (soft reset). There are uncommon cases of complete, irreversible device damage. CIED dysfunction during RT can be observed in approximately 3% of patients. In majority of cases they are asymptomatic, although in literature there are descriptions of deterioration of clinical status due to bradycardia or exacerbation of heart failure. The most important factor of device malfunction is radiotherapy with photons of energy >10 MV or protons despite energy used. So far there were no cases published with inadequate ICD therapies due to the presence of electromagnetic field interference during RT. Because patients with CIED undergoing RT need complex care to achieve high level of safety, experts of Heart Rhythm Society establish document, published in 2017 which summarized current knowledge about this group of patients. The document contains guidelines on peri-radiotherapy care of patients with CIED.

scholarly journals Politeness of Vietnamese Students in Writing Request Email in English: a Course-based and Socio-pragmatic Study

2020 ◽  
Vol 2 (2) ◽  
pp. 109-128
Author(s):  
Thi Minh Trang Pham ◽  
Aiden Yeh
Keyword(s):  
Critical Discourse Analysis ◽  
Cultural Awareness ◽  
Critical Discourse ◽  
Linguistic Knowledge ◽  
Learning And Teaching ◽  
Politeness Strategies ◽  
High Level ◽  
Pragmatic Knowledge ◽  
Determining Factor

This exploratory study investigates politeness strategies employed by Vietnamese EFL learners when writing English request emails sent to foreign and Vietnamese professors and school staff. A corpus-based critical discourse analysis is used to analyze sub-elements of politeness including the degree of imposition, terms of address, request-giving strategy and lexicon-syntactic modifier. The results support the assumption that Vietnamese language pragmatic knowledge is deeply ingrained and has tremendous influence on students’ L2 email writing skills. The study also reveals that Vietnamese students applied a high level of imposition with formal term of address and salutation, directness strategies with the overuse of “please” and other hedges. While gender is not a determining factor, the inflexible adoption of fixed phrases and syntactic-lexical devices were attributed to the lack of sociopragmatic competence. Thus, apart from linguistic knowledge, the role of cultural awareness and socio-pragmatic knowledge should be highlighted in communicative English learning and teaching.

Echinochloa crus-galli (barnyard grass).

2021 ◽  
Author(s):  
Julissa Rojas-Sandoval ◽  
Pedro Acevedo-Rodríguez
Keyword(s):  
Soil Nitrogen ◽  
Crop Yields ◽  
Grass Species ◽  
Coastal Forests ◽  
Virus Diseases ◽  
Forage Crops ◽  
Barnyard Grass ◽  
Natural Grasslands ◽  
The World ◽  
Environmental Weed

Abstract E. crus-galli is a grass species included in the Global Compendium of Weeds (Randall, 2012) and which is considered one of the world's worst weeds. This species has the capability to reduce crop yields and cause forage crops to fail by removing up to 80% of the available soil nitrogen. E. crus-galli is considered the world's worst weed in rice paddies and has been also listed as a weed in at least other 36 crops throughout tropical and temperate regions of the world (Holm et al., 1991). The high levels of nitrates it accumulates can poison livestock. It also acts as a host for several mosaic virus diseases. E. crus-galli is also considered an environmental weed that has become invasive in natural grasslands, coastal forests and disturbed sites in Asia, Africa, Australia, Europe and America (FAO, 2014; USDA-ARS, 2014).

scholarly journals Uremic Toxins and Vascular Dysfunction

Toxins ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 404 ◽  
Author(s):  
Isabelle Six ◽  
Nadia Flissi ◽  
Gaëlle Lenglet ◽  
Loïc Louvet ◽  
Said Kamel ◽  
...  
Keyword(s):  
Current Knowledge ◽  
Vascular Dysfunction ◽  
Essential Element ◽  
Uremic Toxins ◽  
Nitric Oxide Production ◽  
Conventional Risk Factor ◽  
Vascular Calcifications ◽  
Cardiovascular Pathologies ◽  
Determining Factor

Vascular dysfunction is an essential element found in many cardiovascular pathologies and in pathologies that have a cardiovascular impact such as chronic kidney disease (CKD). Alteration of vasomotricity is due to an imbalance between the production of relaxing and contracting factors. In addition to becoming a determining factor in pathophysiological alterations, vascular dysfunction constitutes the first step in the development of atherosclerosis plaques or vascular calcifications. In patients with CKD, alteration of vasomotricity tends to emerge as being a new, less conventional, risk factor. CKD is characterized by the accumulation of uremic toxins (UTs) such as phosphate, para-cresyl sulfate, indoxyl sulfate, and FGF23 and, consequently, the deleterious role of UTs on vascular dysfunction has been explored. This accumulation of UTs is associated with systemic alterations including inflammation, oxidative stress, and the decrease of nitric oxide production. The present review proposes to summarize our current knowledge of the mechanisms by which UTs induce vascular dysfunction.

scholarly journals Optimization of Herbicide Use: Study on Spreading and Evaporation Characteristics of Glyphosate-Organic Silicone Mixture Droplets on Weed Leaves

Agronomy ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 547 ◽  
Author(s):  
Li ◽  
Travlos ◽  
Qi ◽  
Kanatas ◽  
Wang
Keyword(s):  
Leaf Surface ◽  
Orthogonal Experiment ◽  
Digital Camera ◽  
Weed Species ◽  
Coverage Area ◽  
Binary Images ◽  
Spread Area ◽  
Droplet Sizes ◽  
Groove Structure ◽  
Herbicide Use

Herbicide deposition rate can be affected by the leaf surface features of weeds and have a significant impact on the overall efficacy. In this paper, an orthogonal experiment was conducted to investigate the differences of droplet evaporation and spreading characteristics corresponding to weed leaf surface with hairy, waxy and rough (ridged) structures. Three weed species—Descurainia sophia, Lepidium lotifolium, and Lolium temulentum—were included in the study, representing these three leaf structures respectively. Glyphosate sprays with organic silicone surfactant in different concentrations were composed for the test. Single droplets with two diameters of 0.05 μL and 0.1 μL were deposited on the leaves to evaluate the evaporation and spreading characteristics. A digital camera was used and the evaporation duration and the maximum droplet coverage images could be captured and extracted from the recorded videos. The Image Processing Toolbox in Matlab was applied to segment the images for droplet and leaf background and the binary images’ pixel numbers were counted for coverage area calculation. The results revealed that the evaporation duration was reduced with the increase of the organic silicone concentration, while the spread area was expanded. The droplet spread more widely and evaporated faster on D. sophia leaves than on the leaves with L. lotifolium and L. temulentum surfaces. The spreading area and evaporation duration varied much faster on L. lotifolium leaves than on the leaves of other weed species. The droplet sizes affected spreading more significantly on L. temulentum leaf surface, as the spreading procedure of small size droplets was restrained by the groove structure. The results of this study would benefit the consideration of the farmers when selecting the proper nozzle code and the determining of the surfactant mixture in order to optimize the use of herbicides like glyphosate.

Electrocatalytic reduction of nitrate and selenate by NapAB

2011 ◽  
Vol 39 (1) ◽  
pp. 236-242 ◽  
Author(s):  
Andrew J. Gates ◽  
Clive S. Butler ◽  
David J. Richardson ◽  
Julea N. Butt
Keyword(s):  
Cytoplasmic Membrane ◽  
Current Knowledge ◽  
Reductase Activity ◽  
Protonmotive Force ◽  
Metabolic Diversity ◽  
Protein Film ◽  
Carbon Substrates ◽  
Redox Poise ◽  
Paracoccus Pantotrophus ◽  
High Level

Bacterial cellular metabolism is renowned for its metabolic diversity and adaptability. However, certain environments present particular challenges. Aerobic metabolism of highly reduced carbon substrates by soil bacteria such as Paracoccus pantotrophus presents one such challenge since it may result in excessive electron delivery to the respiratory redox chain when compared with the availability of terminal oxidant, O2. The level of a periplasmic ubiquinol-dependent nitrate reductase, NAP, is up-regulated in the presence of highly reduced carbon substrates. NAP oxidizes ubiquinol at the periplasmic face of the cytoplasmic membrane and reduces nitrate in the periplasm. Thus its activity counteracts the accumulation of excess reducing equivalents in ubiquinol, thereby maintaining the redox poise of the ubiquinone/ubiquinol pool without contributing to the protonmotive force across the cytoplasmic membrane. Although P. pantotrophus NapAB shows a high level of substrate specificity towards nitrate, the enzyme has also been reported to reduce selenate in spectrophotometric solution assays. This transaction draws on our current knowledge concerning the bacterial respiratory nitrate reductases and extends the application of PFE (protein film electrochemistry) to resolve and quantify the selenate reductase activity of NapAB.

C1-Inactivator as a Determining Factor in Contact Activation of Fibrinolysis

1975 ◽  
Author(s):  
C. Kluft
Keyword(s):  
Fibrinolytic Activity ◽  
Slow Rate ◽  
Contact Activation ◽  
Activation Rate ◽  
Activity Generation ◽  
High Level ◽  
Fletcher Factor ◽  
Determining Factor

The rate of contact activation of fibrinolysis is considered to reflect the activation rate of proactivator and Hageman factor. This study was undertaken to determine the role of Cl-inactivator in this process.Contact activation of fibrinolysis was performed according to Ogston et al. (1969), J. Clin. Invest. 48, 1786-1801. The rate of activity generation was measured in plasma with various levels of Cl-inactivator and appeared to be dependent on that level; i.e., a high level of Cl-inactivator corresponds with a slow rate of activity generation.It has recently been demonstrated that the fibrinolytic activity of euglobulin fractions is strongly inhibited by Cl-inactivator also present in this fraction. The activity generation of contact activation is found to be accompanied by a gradual decrease in functional Cl-inactivator in the euglobulin fraction. The fibrinolytic activity is set free by this disappearance of inhibition.It is concluded that the rate of contact activation of fibrinolysis must be interpreted in terms of the inactivation of Cl-inactivator rather than of the activation of proenzymes. All enzymes capable of inactivating Cl-inactivator can contribute to the process of contact activation of fibrinolysis. This mechanism might account for the observed defects in fibrinolysis in vitro in Fletcher Factor deficient patients.

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