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This research aimed to evaluate the absorption and translocation of(14)C-glyphosate inUrochloa brizanthacv. Marandu subjected to different light availabilities. Six light conditions were studied: application followed by 24, 48 or ...
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This research aimed to evaluate the absorption and translocation of(14)C-glyphosate inUrochloa brizanthacv. Marandu subjected to different light availabilities. Six light conditions were studied: application followed by 24, 48 or 72 h of dark, 72 h of light, 24 h of dark + 48 h of light and daytime in different evaluation times: 0, 3, 6, 12, 24, 48, and 72 h after application of(14)C-glyphosate (1.67 kBq/plant). The herbicide absorption was higher in plants with less light availability at 72 HAA (48 and 21% for 72 h of darkness and 72 h of light, respectively); however, there was a greater translocation of(14)C-glyphosate to roots in the high availability of light (23 and 5% for 72 h of light and 72 h of dark, respectively). Thus, inU. brizanthaplants, under conditions of greater light availability,C-14-glyphosate was less absorbed, but the product was more translocated. It is recommended that farmers to apply glyphosate at daytime since the light positively favored translocation, which is essential to the herbicidal activity.
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Ever since it was approved by the FDA as a food additive in 1992, gellan, a polyanionic exopolysaccharide from microbial culture, has become a very important polymer for biological applications. The area of its applications has ra...
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Ever since it was approved by the FDA as a food additive in 1992, gellan, a polyanionic exopolysaccharide from microbial culture, has become a very important polymer for biological applications. The area of its applications has rapidly expanded in the pharmaceutical and cosmetic fields, food, medicine, tissue engineering and biotechnology. This paper aims to expand the previous review that presents the use of gellan in the food industry and make an overview of other polysaccharide bioapplications. Considering the interest it has attracted in recent years, the paper details the use of gellan in pharmacy, medicine and tissue engineering. Also, other gellan bioapplications in cosmetics, biotechnology, microbiology are concisely presented.
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Inkjet printing is a rapidly growing commercial process for applications that depend on precisely patterning micro-scale droplets. These applications increasingly require complex fluids, introducing viscoelastic properties which p...
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Inkjet printing is a rapidly growing commercial process for applications that depend on precisely patterning micro-scale droplets. These applications increasingly require complex fluids, introducing viscoelastic properties which play an important role in droplet formation. The objective of this study is to determine how to obtain single, uniform and spherical ("successful") droplets from aqueous solutions of sodium alginate with a piezoelectric drop-on-demand printing method. In order to control the volume and velocities of droplets, the effect on the droplet formation of the characteristics of the waveform such as voltage amplitude and dwell time is studied. The results depend also on the fluid rheology. The viscosity of the chosen fluid is a function of the concentration, as the viscoelastic properties increase at higher concentration. In this paper, the droplet formation process is characterized in terms of both the waveform and the rheological properties of the solution. The characterization of the fluids and waveform will be pursued first and the droplet formation and its control will be studied. Finally, the results will be presented with a map in ranges of the Ohnesorge, Deborah and Weber numbers.
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Here we explore the applicability of the dipeptidyl peptidase IV (DPPIV/CD26) based prodrug approach to a variety of amine-containing drugs. Efficient procedures have been developed for the synthesis of dipeptide and tetrapeptide ...
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Here we explore the applicability of the dipeptidyl peptidase IV (DPPIV/CD26) based prodrug approach to a variety of amine-containing drugs. Efficient procedures have been developed for the synthesis of dipeptide and tetrapeptide amide prodrugs including N-acylation protocols of the exocyclic amino function of cytidine and adenosine nucleosides. Our studies demonstrated that XaaPro dipeptides linked to a free amino group present on an aromatic ring or on a sugar entity are prodrugs that efficiently release the parent drug upon conversion by purified DPPIV/CD26 as well as soluble DPPIV/CD26 in bovine and human serum. Vildagliptin, a specific inhibitor of DPPIV/CD26, was able to completely block the hydrolysis of the prodrugs in the presence of purified CD26 but also in human and bovine serum. When the amino group is present on a pyrimidine or purine ring, the dipeptide derivatives are chemically unstable, whereas the tetrapeptide derivatives (i.e., ValProValPro or ValAlaValPro) were much more stable in solution and efficiently converted to the parent drug by the action of DPPIV/CD26. This DPPIV/CD26-directed prodrug technology can be useful to increase solubility of the parent drug molecules and/or to allow better formulation properties.
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Palmer amaranth is the most common and troublesome broadleaf weed species of rice in Mississippi because of the effects of early-season interference and infestations on rice levees, and herbicides for residual or POST control of P...
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Palmer amaranth is the most common and troublesome broadleaf weed species of rice in Mississippi because of the effects of early-season interference and infestations on rice levees, and herbicides for residual or POST control of Palmer amaranth in rice are limited. Three studies were conducted in 2012 and 2013 to evaluate application rates and timings of saflufenacil in rice and to determine the influence of adjuvants when mixed with saflufenacil applied POST. In a PRE study, no injury occurred after saflufenacil PRE, and no control was observed from carfentrazone. Hemp sesbania and Palmer amaranth control increased with increasing saflufenacil rate when applied PRE. Hemp sesbania control with saflufenacil at any rate PRE was <= 25% at 35 d after treatment (DAT). Palmer amaranth and ivyleaf morningglory control with saflufenacil at 75 g ai ha(-1) PRE was >= 94% 35 DAT. In a POST study, rice injury was influenced by application timing and rate of saflufenacil; however, efficacy was not. Rice injury with saflufenacil at 25 g ha(-1) and carfentrazone early POST (EPOST) and late POST was similar 7DAT. Saflufenacil at 50 and 75 g ha(-1) EPOST were the most injurious 7 DAT. Control of hemp sesbania and ivyleaf morningglory was similar for all rates of saflufenacil and carfentrazone; however, Palmer amaranth control with saflufenacil at any rate was greater than that of carfentrazone 14 and 28 DAT. In an adjuvant study, rice injury was influenced by adjuvant and saflufenacil rate. Saflufenacil applied alone or in mixture with crop oil concentrate (COC) was least injurious, and saflufenacil at 50 g ha(-1) wasmore injurious than saflufenacil at 25 g ha(-1). Saflufenacil applied in combination with any adjuvant provided better control of hemp sesbania and Palmer amaranth than saflufenacil alone. On the basis of this research, saflufenacil should be applied PRE at 50 or 75 g ha(-1), depending on weed spectrum, and POST applications should be made at 25 g ha(-1) in combination with COC after the two-leaf rice growth stage.
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In ubiquitous computing, or ubiquitous network environment, many sensors and devices are embedded in the environment. Moreover, information appliances and smart space technologies allow users to enjoy high computational power, whi...
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In ubiquitous computing, or ubiquitous network environment, many sensors and devices are embedded in the environment. Moreover, information appliances and smart space technologies allow users to enjoy high computational power, which also gives freedom and extrication from traditional computing style that often caused users' inconvenience and restriction of their demands and needs. However, due to the characteristics of ubiquitous computing, application's high adaptability to the changes of environments is required. To achieve this high adaptability of applications, we introduce a design approach of "snapshot-based application." The snapshot-based application can store its status as a snapshot. By utilizing the snapshot, an application can be recreated as it is in the status of the snapshot. In this paper, we propose an application framework named "u-Snap," which realizes snapshot-based applications. We have exemplified the effectiveness of this framework with implementation of "u-Photo," which utilize a snapshot of an application as contextual information that is embedded in a photo image.
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The class of probability distributions possessing the almost-lack-of-memory property appeared about 20 years ago. It reasonably took place in research and modeling, due to its suitability to represent uncertainty in periodic rando...
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The class of probability distributions possessing the almost-lack-of-memory property appeared about 20 years ago. It reasonably took place in research and modeling, due to its suitability to represent uncertainty in periodic random environment. Multivariate version of the almost-lack-of-memory property is less known, but it is not less interesting. In this paper we give the copula of the bivariate almost-lack-of-memory (BALM) distributions and discuss some of its properties and applications. An example shows how the Marshal-Olkin distribution can be turned into BALM and what is its copula.
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Applications of nuclear spectroscopic techniques are well established in chemistry and biochemistry, where, for example, conventional nuclear magnetic resonance (NMR) spectroscopy is an indispensable analytical tool [1]. NMR is us...
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Applications of nuclear spectroscopic techniques are well established in chemistry and biochemistry, where, for example, conventional nuclear magnetic resonance (NMR) spectroscopy is an indispensable analytical tool [1]. NMR is used routinely to identify small organic molecules in quality control, and in more complex research applications to elucidate structure and dynamics of large biomolecules such as proteins and nucleic acids. Additionally, magnetic resonance (MR) scanners are available at most large hospitals for imaging, and it is now even possible to acquire affordable desk top NMR instruments with permanent magnets, aimed at small businesses and educational institutions. However, conventional NMR spectroscopy faces certain limitations, mainly due to: (1) relatively poor sensitivity and (2) the fact that there are elements that are difficult to detect, because of poor NMR response. To overcome the first problem, a variety of hyperpolarization techniques have been developed, reaching nuclear spin polarization in the % range [2], which is far beyond what may be achieved at thermal equilibrium even in strong external magnetic fields at room temperature. β-detected NMR (β-NMR) spectroscopy belongs to this family of specialized NMR techniques, where considerable nuclear spin polarization is created prior to the NMR measurement. The sensitivity of β-NMR spectroscopy is further enhanced, as it is a radioisotope-based technique, exploiting the detection of anisotropic emission of β-particles from the spin polarized nuclei, vide infra, leading to a billion-fold or higher increase in sensitivity as compared to conventional NMR spectroscopy on stable isotopes. In addition to this, some of the elements which are problematic in conventional NMR spectroscopy, such as Mg, Ca, Cu, and Zn, already are or might be accessible with β-NMR spectroscopy [3–5]. Several applications of β-NMR spectroscopy in nuclear, solid state physics, and materials science have been published over the past decades [3–14] and references therein, and with the project described herein, we aim to advance the applications to solution chemistry and biochemistry [5].
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The electron-transfer process is the pivotal step in SmI2 reductions.[1] In most cases, this step seems to be endothermic and slow. It could be enhanced by increasing the reduction potential of SmI2, for example, by using additive...
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The electron-transfer process is the pivotal step in SmI2 reductions.[1] In most cases, this step seems to be endothermic and slow. It could be enhanced by increasing the reduction potential of SmI2, for example, by using additives such as hexamethylphosphoramide (HMPA).[2] Another way to increase the reduction potential of SmI2 is by irradiation.[3] However, in contradistinction to the HMPA method, the range of applicability of this method is surprisingly limited. To the best of our knowledge, the reaction types shown in Scheme 1 are the only examples of the application of this method.[3]
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Restricting application rates is an attractive way for funders to reduce time and money wasted evaluating uncompetitive applications. However, mathematical models show that this could induce chaotic cycles in total application num...
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Restricting application rates is an attractive way for funders to reduce time and money wasted evaluating uncompetitive applications. However, mathematical models show that this could induce chaotic cycles in total application numbers, increasing uncertainty in the funding process. One emergent property is that smaller institutions spend disproportionally more time unfunded.
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