Articles de revues : « Mixtures of g-prior »

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Bovey, Rodney W., et Steven G. Whisenant. « Honey Mesquite (Prosopis glandulosa) Control by Synergistic Action of Clopyralid : Triclopyr Mixtures ». Weed Science 40, n^o 4 (décembre 1992) : 563–67. http://dx.doi.org/10.1017/s0043174500058148.

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Greenhouse and field experiments were conducted to evaluate clopyralid formulations and triclopyr ester alone and in mixtures for control of honey mesquite. In the greenhouse the butoxyethyl ester of triclopyr enhanced activity of the monoethanolamine salt of clopyralid when applied as mixtures for total rates of 210 to 630 g ae ha-1. Greenhouse activity of triclopyr was not enhanced with the addition of clopyralid. In the field, 1989 applications of these same formulations, mixtures, and rates were usually synergistic, with each mixture killing more plants than the combined effect of either herbicide applied alone. For example, clopyralid plus triclopyr at 140 plus 140 g ae ha-1killed 87% of the plants. When applied alone at 140 g ha-1neither herbicide killed >27% of the plants. Honey mesquite response to the potassium or oleylamine salt of clopyralid was similar to the monoethanolamine salt when applied alone or in mixtures with triclopyr ester. Effectiveness of these mixtures in 1990 was similar to the 1988 and 1989 applications except that two to three times more herbicide was required for high mortality in 1990 because of unfavorable environment and plant growth prior to treatment.

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Waggoner, Brock S., Thomas C. Mueller, Jason A. Bond et Lawrence E. Steckel. « Control of Glyphosate-Resistant Horseweed (Conyza canadensis) with Saflufenacil Tank Mixtures in No-Till Cotton ». Weed Technology 25, n^o 3 (septembre 2011) : 310–15. http://dx.doi.org/10.1614/wt-d-10-00161.1.

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Glyphosate-resistant (GR) horseweed management continues to be a challenge in no-till cotton systems in Tennessee and Mississippi. Field studies were conducted in 2009 and 2010 to evaluate saflufenacil in tank mixtures with glyphosate, glufosinate, or paraquat on GR horseweed prior to planting cotton. Saflufenacil and saflufenacil tank mixtures were applied 7 d before planting (DBP). Three broad spectrum herbicides were tank-mixed with saflufenacil at rates of 0, 6.3, 12.5, 25, and 50 g ai ha−1. Saflufenacil at 25 and 50 g ai ha−1in tank mixture with all three broad-spectrum herbicides provided similar GR horseweed control when compared to the current standard of glyphosate + dicamba. Across all saflufenacil rates, lint cotton yield among the glyphosate, glufosinate, and paraquat tank mixture treatments did not differ from each other. Control of horseweed with 25 or 50 g ha−1of saflufenacil across all tank mixtures also was not different from the standard of glyphosate + dicamba. Moreover, saflufenacil, on silt loam soil evaluated in this study, showed no more cotton injury than glyphosate applied 7 d or more before planting. Saflufenacil applied alone at 25 g ha−1provided lower control of GR horseweed than the standard, which translated to lower lint yield compared to the glyphosate + dicamba treatment or saflufenacil with each tank mixture partner. The 12.5 g ha−1rate of saflufenacil tank mixed with either paraquat or glufosinate provided less horseweed control (< 85%) than if higher rates of saflufenacil were used (> 95%). However, lint cotton yield was not different between these treatments. This research suggests that saflufenacil at 25 g ha−1is the most optimal rate for tank mixtures with glyphosate, glufosinate, or paraquat. It also reaffirms earlier research that the 25 g ha−1saflufenacil rate safely can be applied inside the currently labeled 42-d waiting period between a saflufenacil application and cotton planting.

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Lošák, Tomáš, Jaroslav Hlušek, Jiří Jandák, Radek Filipčík, Marie Straková, Ľubica Janků, Helena Hutyrová, Daniela Knotová, Martin Lošák et Magdalena Ševčíková. « The effect of soil applications of zeolite, agrisorb and lignite on the chemical composition of clover-grass mixtures grown in arid conditions of South Moravia ». Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 58, n^o 5 (2010) : 247–54. http://dx.doi.org/10.11118/actaun201058050247.

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The two-year field trial was established in May 2008 on light soil in the cadastre of Ratíškovice near Hodonín in an arid maize-growing production area. Prior to sowing selected soil conditioners were applied in experimental plots of an area of 864 m2 as follows: zeolite (a mineral of high sorption capacity), lignite (the youngest coal containing humus substances) and the supplementary soil substance agrisorb (polymer organic compound capable of holding in its structure and subsequently releasing water) and they were incorporated into a profile of 0.15 m. Including the untreated control the experiment involved 4 treatments. The rates of the conditioners were as follows: zeolite – 3 l . m−2, fraction used 1–2 mm; agrisorb – 20 g . m−2; lignite – 1000 g . m−2. Three types of clover-grass mixtures were sown: landscape mixture with an addition of leguminous plants (seeding rate 200 kg . ha−1), regional mixture (100 kg . ha−1) and annual mixture (70 kg . ha−1). The aboveground biomass taken from an area of 0.05 m2 was sampled in the stage of bud setting with three repetitions to each treatment. In 2008 and 2009 the respective treatments did not significantly change the contents of N, P, K, Ca and Mg in the aboveground biomass of the clover-grass mixtures. The differences in the contents of the macro elements were significant only between the individual types of mixtures and were due to their different botanical composition. Between the years 2008 and 2009 no significant differences were discovered among treatments in terms of the contents of P and K in none of the mixtures, but the Mg content decreased in the second year in most treatments by 50 relative % and more. The contents of N and Ca increased significantly in the second year in the regional and landscape mixtures; in the annual mixture also the Ca content. The year-on-year differences however were seen also in the untreated control showing the apparent effect of the year. A longer period of monitoring is necessary if we are to achieve an objective evaluation of the effect of the applied preparations on the chemical composition of the aboveground biomass.

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Burke, Ian C., Shawn D. Askew, Jerry L. Corbett et John W. Wilcut. « Glufosinate Antagonizes Clethodim Control of Goosegrass (Eleusine indica) ». Weed Technology 19, n^o 3 (septembre 2005) : 664–68. http://dx.doi.org/10.1614/wt-04-214r1.1.

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Because of a previously reported antagonism of clethodim activity by other herbicides, greenhouse experiments were conducted to determine goosegrass control with clethodim and glufosinate postemergence alone, in tank mixtures, and as sequential treatments. Herbicide treatments consisted of glufosinate at 0, 290, or 410 g ai/ha and clethodim at 0, 105, or 140 g ai/ha, each applied alone, in all possible combinations of the above application rates, or sequentially. Glufosinate at either rate alone controlled goosegrass at the two- to four-leaf growth stage <44%, and control was less for goosegrass at the one- to two- and four- to six-tiller growth stages. Clethodim controlled two- to four-leaf and one- to two-tiller goosegrass 91 and 99% at application rates of 105 and 140 g/ha, respectively, and controlled four- to six-tiller goosegrass 68 and 83% at application rates of 105 and 140 g ai/ha, respectively. All tank mixtures of glufosinate with clethodim reduced goosegrass control at least 52 percentage points when compared to the control with clethodim alone. Glufosinate at 290 or 410 g/ha when applied sequentially 7 or 14 d prior to clethodim reduced goosegrass control at least 50 percentage points compared to the control obtained with clethodim applied alone. Clethodim at rates of 105 or 140 g/ha when applied 7 or 14 d prior to glufosinate controlled goosegrass equivalent to the control obtained with each respective rate of clethodim applied alone at the two- to four-leaf and one- to two-tiller growth stage. Clethodim should be applied to goosegrass no larger than at the one- to two-tiller growth stage at least 7 d prior to glufosinate application or 14 d after a glufosinate application for effective goosegrass control.

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Zouaoui, Younes, Ferhat Benmahiddine, Ammar Yahia et Rafik Belarbi. « Hygrothermal and Mechanical Behaviors of Fiber Mortar : Comparative Study between Palm and Hemp Fibers ». Energies 14, n^o 21 (1 novembre 2021) : 7110. http://dx.doi.org/10.3390/en14217110.

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This paper presents an experimental investigation of the hygrothermal and mechanical properties of innovative mortar mixtures reinforced with natural fibers. Fibers extracted from palm stems (PS) and hemp (HF) were evaluated at different percentages. Scanning electron microscope (SEM) observations showed that the PS fibers have rough surfaces and very complex microstructures. Prior to their incorporation into the mortar, the fibers were subjected to different treatments to reduce their hydrophilic character. The employed treatments showed good efficiency in reducing the water absorption of both PS and HF fiber types. Furthermore, the mortar mixtures incorporating these fibers exhibited low thermal conductivity and excellent moisture buffering capacity. Indeed, the moisture buffer value (MBV) of the investigated mixtures ranged between 2.7 [g/(%HR·m2)] and 3.1 [g/(%HR·m2)], hence providing them excellent moisture regulator character. As expected, the fiber mortar mixtures showed very high porosity and low compressive strength ranging between 0.6 and 0.9 MPa after 28 days of age. The low-environmental footprint materials developed in this study are intended for thermal insulation and building filling.

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Wall, David A. « Fluazifop-P Tank-Mixtures with Clethodim for Annual Grass Control in Flax (Linum usitatissimum) ». Weed Technology 8, n^o 4 (décembre 1994) : 673–78. http://dx.doi.org/10.1017/s0890037x00028505.

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Field studies were undertaken in 1992 and 1993 to investigate the control of wild oat and green foxtail in flax with reduced rates of fluazifop-P and clethodim applied as tank-mixtures. Fluazifop-P plus clethodim at 50 + 18 g ai/ha controlled wild oat and green foxtail and was as effective as full rates of either herbicide applied alone. These rates represent a 20% reduction in total amount of active ingredient required to control wild oat and green foxtail. Application of fluazifop-P, and/or clethodim prior to the 3- to 4-leaf stage failed to control late emerging grass weeds. Application of graminicide mixtures at or after the 3- to 4-leaf stage controlled late emerging grass weeds and did not affect flax yield. When applied late, fluazifop-P at 175 g/ha tended to reduce flax yield, although weed control was acceptable and no foliar injury was observed following treatment. The efficacy of graminicide mixtures was reduced by addition of bromoxynil plus MCPA to the spray mix.

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Harre, Nick T., Julie M. Young et Bryan G. Young. « Glyphosate-Induced Antagonism in Rapid Response Giant Ragweed (Ambrosia trifida) ». Weed Technology 32, n^o 1 (17 novembre 2017) : 52–59. http://dx.doi.org/10.1017/wet.2017.92.

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AbstractGlyphosate application to the rapid-response (RR) biotype of glyphosate-resistant (GR) giant ragweed ensues in loss of foliage via rapid tissue death, thereby reducing glyphosate translocation. Experiments were performed to determine if this GR response, in contrast to a non-rapid response (NRR) GR biotype, results in antagonism of the selective herbicides atrazine, cloransulam, dicamba, lactofen, and topramezone. Application of glyphosate at 1,680 g ae ha–1in the greenhouse resulted in antagonism between all five selective herbicides for the RR biotype, whereas glyphosate applied at 420 g ha–1was antagonistic only for cloransulam. Application of selective herbicides 2 d prior to glyphosate treatment avoided the antagonism observed in the RR biotype. In the field, glyphosate mixtures with dicamba and topramezone were antagonistic on the RR biotype across both 2015 and 2016 field seasons. Thus, the RR effectively reduces glyphosate efficacy but also has potential to diminish the activity of glyphosate mixtures with selective herbicides, and the degree of antagonism between these mixtures escalates at increasing glyphosate rates.

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Harris, D. M. « Pre-incubation of microbes for use in the Pressure Transducer Technique (PTT) of feed evaluation - effect of basal feed composition ». Proceedings of the British Society of Animal Science 1996 (mars 1996) : 220. http://dx.doi.org/10.1017/s1752756200594125.

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The use of the Pressure Transducer Technique (PTT) to evaluate feed degradation as described by Theodorou et al (1994) recognises the presence of a lag phase (1-2h) after introducing the microbial innocula to the feed under investigation. Previous work has shown that this can be reduced by incubating the microbes with a basal feed for 24h prior to the addition of a test feed. This work considered the effect of the composition of this basal feed.Four basal mixtures, Grass silage/conc(G), Hay/cone (H), Maize silage/conc: (M), Whole crop wheat/caustic wheat/cone (W) were prepared plus two mixtures based on purified nutrients to give high Starch (St) and high Cellulose (Ce) contents. 20ml strained, homogenised bovine rumen liquor was added to bottles containing 180ml of media and 1.5g DM of each basal mixture. After 24h of vented incubation at 39Â°C 1g DM of test feed, (either barley grain or straw both milled to 1 mm) was added and gas production measured at decreasing frequencies over the next 72h. Cumulative gas production at 72h were calculated (Table 1).

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Harris, D. M. « Pre-incubation of microbes for use in the Pressure Transducer Technique (PTT) of feed evaluation - effect of basal feed composition ». Proceedings of the British Society of Animal Science 1996 (mars 1996) : 220. http://dx.doi.org/10.1017/s0308229600031834.

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The use of the Pressure Transducer Technique (PTT) to evaluate feed degradation as described by Theodorou et al (1994) recognises the presence of a lag phase (1-2h) after introducing the microbial innocula to the feed under investigation. Previous work has shown that this can be reduced by incubating the microbes with a basal feed for 24h prior to the addition of a test feed. This work considered the effect of the composition of this basal feed.Four basal mixtures, Grass silage/conc(G), Hay/cone (H), Maize silage/conc: (M), Whole crop wheat/caustic wheat/cone (W) were prepared plus two mixtures based on purified nutrients to give high Starch (St) and high Cellulose (Ce) contents. 20ml strained, homogenised bovine rumen liquor was added to bottles containing 180ml of media and 1.5g DM of each basal mixture. After 24h of vented incubation at 39Â°C 1g DM of test feed, (either barley grain or straw both milled to 1 mm) was added and gas production measured at decreasing frequencies over the next 72h. Cumulative gas production at 72h were calculated (Table 1).

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Orr, R. J., et T. T. Treacher. « Effects of ratio of white clover to grass in silage and concentrate supplementation on intake and performance of ewes in late pregnancy ». Proceedings of the British Society of Animal Production (1972) 1987 (mars 1987) : 76. http://dx.doi.org/10.1017/s030822960003511x.

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Widespread adoption of sheep systems based on mixed swards of white clover and grass may result in conservation cuts with a high proportion of clover, which will affect the intake of the silage or hay. The effect of proportion of clover in silage on voluntary intake was measured by offering mixtures of clover and grass silage with clover proportions of 0, 0.20, 0.40 and 0.60 with (S) and without (U) a ration of 600 g fresh weight per day of a barley, soya and fishmeal concentrate to 78 Finn Dorset ewes. The concentrate was formulated to have a crude protein content (CP) of 160 g per kg DM with 30 g per kg DM derived from fishmeal. The silages were made separately in 1984, with formic acid added at approximately 3.51 per tonne, from uninterrupted spring growths of perennial ryegass (Loliua perenre cv. Melle) cut on 16 June and white clover (Trifolium repens cv. Blanca) cut on 17 July and both were chopped. Mixtures of the two silages were made for each individual ewe separately each day, immediately prior to feeding.

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Gauvin, David V., et Frank A. Holloway. « The discriminative stimulus properties of an ethanol-nicotine mixture in rats ». Journal of Psychopharmacology 7, n^o 1_suppl (janvier 1993) : 52–62. http://dx.doi.org/10.1177/026988119300700109.

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Sprague-Dawley rats were trained to discriminate between saline (SAL) and an ethanol-nicotine mixture (0.5 g/kg ethanol plus 0.5 mg/kg nicotine) administered 15 min prior to a 15-min drug discrimination training session under a FR-10 schedule of reinforcement. The mixture dose ratio was adjusted after training to obtain a drug mixture with which both individual drugs contributed about equally to the stimulus control (1.0 g/kg ethanol plus 0.3 mg/kg nicotine). The animals were then retrained for 32 sessions using this new mixture. After training, neither nicotine nor ethanol, when tested singly, engendeded > 90% mixture-appropriate responding up to test doses that suppressed responding. Complete generalization occurred when the training doses of either nicotine or ethanol were administered in combination with various doses of the alternate drug element. (+)Nicotine, amphetamine and caffeine engendered dose-dependent increases in responses emitted on the mixture-appropriate lever. Pentobarbital and chloral hydrate only partially generalized to the training mixture. However, depressant/stimulant combinations of chloral hydrate+caffeine and pentobarbital+amphetamine produced complete generalization. The data suggest: (1) drug mixtures are not normally perceived as new entities distinct from their component elements; (2) training dose ratio may influence the characteristics of mixture discriminations; (3) stimulus element saliency may be a factor determining the nature of discriminative control by drug mixture cues; and (4) the ethanol-nicotine cue was most likely based on non-specific depressant/stimulant effects of these drugs.

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Baptista, Patrícia, Pedro Felizardo, José C. Menezes et M. Joana Neiva Correia. « Monitoring the Quality of Oils for Biodiesel Production Using Multivariate near Infrared Spectroscopy Models ». Journal of Near Infrared Spectroscopy 16, n^o 5 (1 janvier 2008) : 445–54. http://dx.doi.org/10.1255/jnirs.814.

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Biodiesel is a mixture of fatty acid methyl esters, derived from vegetable oils or animal fats, which is usually produced by a transesterification reaction, where the oils or fats react with an alcohol in the presence of a catalyst. The quality of the oils used for biodiesel production strongly influences the final properties of biodiesel, namely its compliance to the European Standard. This work reports the use of near infrared (NIR) spectroscopy in the quality control of several oil properties, such as the iodine value, the water content and the acid number but, more importantly, the weight–weight percentages (wt%) of soybean, palm and rapeseed oil in mixtures. Principal component analysis was used to perform a qualitative analysis of the spectra, whereas partial least squares regression allowed the development of calibration models between analytical reference data and NIR spectra. The calibration ranges were 60–126 g I2 100 g−1 for the iodine value, 478–2500 mg kg−1 for the water content and 0.13-6.56 mg KOH g−1 for the acid number, whereas the validation errors were around 3.1 g I2 100 g−1, 111 mg kg−1 and 0.22 mg KOH g−1, respectively. The results obtained show that NIR spectroscopy is a promising technique to carry out the quality control of the commonly used vegetable oils for biodiesel production, namely the quality assurance and authenticity. Furthermore, it is of great value to have a simple, fast and reliable method to identify the composition of an oil mixture and/or some of its quality parameters, prior to storage or upon admission of a new lot of oil.

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Gopalakrishnan, Sujatha M., Betsy Mammen, Martin Schmidt, Bernd Otterstaetter, Willi Amberg, Wolfgang Wernet, James L. Kofron, David J. Burns et Usha Warrior. « An Offline-Addition Format for Identifying GPCR Modulators by Screening 384-Well Mixed Compounds in the FLIPR ». Journal of Biomolecular Screening 10, n^o 1 (février 2005) : 46–55. http://dx.doi.org/10.1177/1087057104270017.

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Although fluorescence imaging plate reader (FLIPR)-based assays have been widely used in high-throughput screening, improved efficiencies in throughput and fidelity continue to be investigated. This study presents an offline compound addition protocol coupled with a testing strategy using mixtures of compounds in a 384-well format to identify antagonists of the neurokinin-1 receptor expressed in the human astrocytoma cell line (U373 MG). Substance P evoked a concentration-dependent increase in intracellular cellular Ca2+ with an EC50 value of 0.30 ± 0.17 nM, which was inhibited by neurokinin-1 (NK1) antagonists L-733,060 and L-703,606. Test compounds, as mixtures of 10 compounds/well, were added to the cells offline using an automated dispensing unit and incubated prior to performing the assay in the FLIPR. Using the offline protocol, a higher through put of ~200,000 compounds was achieved in an 8-h working day, and several novel structural classes of compounds were identified as antagonists for the NK1 receptor. These studies demonstrate that the offline compound addition format using a mixture of compounds in a 384-well FLIPR assay provides an efficient platform for screening and identifying modulators for G-protein-coupled receptors. ( Journal of Biomolecular Screening 2005:46-55)

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Pruvot, I., C. Fievet, C. Durieux, N. Vu Dac et J. C. Fruchart. « Electroimmuno- and immunonephelometric assays of apolipoprotein A-I by using a mixture of monoclonal antibodies. » Clinical Chemistry 34, n^o 10 (1 octobre 1988) : 2048–52. http://dx.doi.org/10.1093/clinchem/34.10.2048.

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Abstract The use of mixtures of well-defined monoclonal antibodies may represent a step forward in the standardization of immunochemical assays. We developed and optimized working conditions for using such a mixture to determine apolipoprotein A-I in human sera by two independent techniques (electroimmuno- and immunonephelometric-assays). Six monoclonal antibodies, each addressed to distinct epitopes located at the surface of apolipoprotein A-I, were used in combination to permit a reproducible measurement of the protein, without prior delipidation of samples. Parallel standard curves for a high-density lipoprotein subfraction (HDL3, the primary standard) and a reference serum (the secondary standard) were obtained. Within- and between-run coefficients of variation were acceptable for both methods. Apolipoprotein A-I concentrations, as measured in 60 subjects selected to present a large range of apolipoprotein content by electroimmunoassay (y1) and immunonephelometric assay (y2) with monoclonal antibodies, compared well with those measured by the same techniques but with polyclonal antibodies (x): r1 = 0.96, r2 = 0.99; y1 = 1.19x - 0.11 g/L, y2 = 0.98x. Comparison of results obtained by electroimmunoassay and immunonephelometric assay performed with monoclonal antibodies was also good: r = 0.96; y2 = 1.08y1 + 0.13 g/L.

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Al-Soud, Waleed Abu, Leif J. Jönsson et Peter Rådström. « Identification and Characterization of Immunoglobulin G in Blood as a Major Inhibitor of Diagnostic PCR ». Journal of Clinical Microbiology 38, n^o 1 (janvier 2000) : 345–50. http://dx.doi.org/10.1128/jcm.38.1.345-350.2000.

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ABSTRACT A major inhibitor of diagnostic PCR in human plasma was identified and the mechanism of inhibition was characterized. Human blood was divided by centrifugation into buffy coat, plasma, platelets, and erythrocytes. All these blood fractions were found to be highly inhibitory to a standardized PCR mixture containing the thermostable DNA polymerase Ampli Taq Gold. PCR inhibitors in human plasma were purified by chromatographic procedures and were characterized by a process of elimination, so that the PCR-inhibitory effects of plasma fractions were tested after each purification step. The major inhibitor in human plasma, as determined by size-exclusion chromatography, anion-exchange chromatography, and chromatofocusing, was found to be immunoglobulin G (IgG) on the basis of N-terminal amino acid sequencing and electrophoretic analysis of the purified polypeptide. When different concentrations of purified plasma IgG (PIgG) were added to PCR mixtures containing 11 different thermostable DNA polymerases and 1 ng of Listeria monocytogenes DNA as template DNA, the only polymerase that resisted inhibition was rTth . The inhibitory effect was reduced when PIgG was heated at 95°C before it was added to PCR or after the addition of excess nontarget DNA to the PCR mixture. However, heating of PIgG together with target DNA at 95°C was found to block the amplification. Inhibition by PIgG may be due to an interaction with single-stranded DNA, which makes the target DNA unavailable for 10 of the DNA polymerases tested. The results show the danger of using boiling as a method of sample pretreatment or using a hot start prior to PCR. The effect of plasma PCR inhibition could be removed by mixing plasma with DNA-agarose beads prior to amplification, while plasma PCR inhibitors were found to bind to the DNA-agarose beads.

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da Silva, Liliane Severino, Justin C. Burt, Mary K. Mullenix et Jennifer J. Tucker. « 174 Forage Production and Nutritive Value of Alfalfa-bermudagrass Mixtures Managed Under Contrasting Defoliation Strategies in the Southeast US ». Journal of Animal Science 99, Supplement_3 (8 octobre 2021) : 96. http://dx.doi.org/10.1093/jas/skab235.172.

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Abstract Incorporation of alfalfa (Medicago sativa) into bermudagrass pastures improves forage quality and decreases the reliance on synthetic nitrogen fertilizer. The objective of this study was to determine forage mass (FM), nutritive value (NV), and botanical composition of ‘Bulldog 805’ alfalfa and ‘Tifton 85’ bermudagrass (T85; Cynodon dactylon) mixtures managed under three defoliation strategies: 1) hay production (H), 2) grazing (G) or 3) dual-purpose (DP) use. The study was conducted in two locations (Headland, AL and Tifton, GA) using a randomized complete block design with two replicates. In spring 2020, grazed plots were divided in four strips and every 7-d, animals were rotated to a new strip and stocking rate was adjusted. Under DP, plots were grazed until mid-July, then forage was harvested in late August. For H plots, forage was harvested every 28 to 35-d. Forage samples were collected prior defoliation to determine FM and on grazed periods, pre- and post-grazing samples and disk meter measurements were collected. Nutritive value responses were determined using near-infrared spectroscopy. There was no effect of defoliation strategy on FM (P = 0.604; mean 3471 kg DM/ha). Greater FM (P = 0.002) was observed in July and August than June (3531 and 3976 vs 2905 kg DM ha-1, SE= 263). This response was associated with an up to 40% increase of T85 proportion in the mixture (P = 0.001). Alfalfa percentage was 78% greater for DP than G (P = 0.029). There were no differences among treatments for NV responses (P > 0.05). Among defoliation periods, crude protein, neutral detergent fiber and acid detergent fiber concentrations ranged from 14 to 22%, 45 to 58% and 28 to 35%, respectively. These preliminary results demonstrate multi-use options for this mixture in the region while aiming for increased forage nutritive value, and extended growing season, and sustainability of forage-livestock systems.

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Hoskinson, Alan R., Wilson T. Rawlins, Kristin L. Galbally-Kinney, Emily Gong et Jeffrey Hopwood. « Production and loss of O₂(¹Δ _g ) at atmospheric pressure using microwave-driven microplasmas ». Journal of Physics D : Applied Physics 55, n^o 12 (29 décembre 2021) : 125208. http://dx.doi.org/10.1088/1361-6463/ac4364.

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Abstract We have used arrays of microwave-generated microplasmas operating at atmospheric pressure to generate high concentrations of singlet molecular oxygen, O2(1Δ g ), which is of interest for biomedical applications. The discharge is sustained by a pair of microstrip-based microwave resonator arrays which force helium/oxygen gas mixtures through a narrow plasma channel. We have demonstrated the efficacy of both NO and less-hazardous N2O additives for suppression of ozone and associated enhancement of the O2(1Δ g ) yield. Quenching of O2(1Δ g ) by ozone is sufficiently suppressed such that quenching by ground state molecular oxygen becomes the dominant loss mechanism in the post-discharge outflow. We verified the absence of other significant gas-phase quenching mechanisms by measuring the O2(1Δ g ) decay along a quartz flow tube. These measurements indicated a first-order rate constant of (1.2 ± 0.3) × 10−24 m3 s−1, slightly slower than but consistent with prior measurements of singlet oxygen quenching on ground state oxygen. The discharge-initiated reaction mechanisms and data analysis are discussed in terms of a chemical kinetics model of the system.

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Lawrence, Benjamin H., Jason A. Bond, Bobby R. Golden, Thomas W. Allen, Daniel B. Reynolds et Taghi Bararpour. « Rice performance following exposure to a sublethal concentration of paraquat applied alone or in mixture with common residual herbicides ». Weed Technology 34, n^o 5 (6 avril 2020) : 675–81. http://dx.doi.org/10.1017/wet.2020.39.

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AbstractIn glyphosate-resistant (GR) cropping systems, paraquat applied in mixtures with residual herbicides prior to crop emergence offers an alternative herbicide mode of action (MOA) to aid in GR weed management. Rice is sensitive to off-target herbicide movement; however, severity of injury can vary with herbicide, rate, and formulation. Therefore, research was conducted from 2015 to 2017 in Stoneville, MS, to characterize rice response to a sublethal concentration of paraquat applied at 84 g ai ha–1 in combination with common residual herbicides. Paraquat plus metribuzin injured rice 68% to 69% 14 and 28 d after treatment (DAT), which was 10% to 13% greater than injury following paraquat alone or paraquat plus fomesafen. Pooled across metribuzin and fomesafen treatments, paraquat reduced rough rice yields 23%. Paraquat plus 10 different residual herbicides injured rice ≥51% 28 DAT and reduced rough rice yields ≥21%. These studies indicate a severe negative impact on rice growth and development following exposure to a sublethal concentration of paraquat alone or in mixture with common residual herbicides. Therefore, applications of paraquat plus residual herbicides to fields in proximity to rice should be avoided if conditions are conducive for off-target movement.

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Xiao, Han, Yang Gu, Yuanyuan Ning, Yunliu Yang, Wilfrid J. Mitchell, Weihong Jiang et Sheng Yang. « Confirmation and Elimination of Xylose Metabolism Bottlenecks in Glucose Phosphoenolpyruvate-Dependent Phosphotransferase System-Deficient Clostridium acetobutylicum for Simultaneous Utilization of Glucose, Xylose, and Arabinose ». Applied and Environmental Microbiology 77, n^o 22 (16 septembre 2011) : 7886–95. http://dx.doi.org/10.1128/aem.00644-11.

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ABSTRACTEfficient cofermentation ofd-glucose,d-xylose, andl-arabinose, three major sugars present in lignocellulose, is a fundamental requirement for cost-effective utilization of lignocellulosic biomass. The Gram-positive anaerobic bacteriumClostridium acetobutylicum, known for its excellent capability of producing ABE (acetone, butanol, and ethanol) solvent, is limited in using lignocellulose because of inefficient pentose consumption when fermenting sugar mixtures. To overcome this substrate utilization defect, a predictedglcGgene, encoding enzyme II of thed-glucose phosphoenolpyruvate-dependent phosphotransferase system (PTS), was first disrupted in the ABE-producing model strainClostridium acetobutylicumATCC 824, resulting in greatly improvedd-xylose andl-arabinose consumption in the presence ofd-glucose. Interestingly, despite the loss of GlcG, the resulting mutant strain 824glcG fermentedd-glucose as efficiently as did the parent strain. This could be attributed to residual glucose PTS activity, although an increased activity of glucose kinase suggested that non-PTS glucose uptake might also be elevated as a result ofglcGdisruption. Furthermore, the inherent rate-limiting steps of thed-xylose metabolic pathway were observed prior to the pentose phosphate pathway (PPP) in strain ATCC 824 and then overcome by co-overexpression of thed-xylose proton-symporter (cac1345),d-xylose isomerase (cac2610), and xylulokinase (cac2612). As a result, an engineered strain (824glcG-TBA), obtained by integratingglcGdisruption and genetic overexpression of the xylose pathway, was able to efficiently coferment mixtures ofd-glucose,d-xylose, andl-arabinose, reaching a 24% higher ABE solvent titer (16.06 g/liter) and a 5% higher yield (0.28 g/g) compared to those of the wild-type strain. This strain will be a promising platform host toward commercial exploitation of lignocellulose to produce solvents and biofuels.

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Wakisaka, Shinji, Yoshifumi Ohshima, Masahiro Ogawa, Tatsurokuro Tochikura et Takashi Tachiki. « Characteristics and Efficiency of Glutamine Production by Coupling of a Bacterial Glutamine Synthetase Reaction with the Alcoholic Fermentation System of Baker’s Yeast ». Applied and Environmental Microbiology 64, n^o 8 (1 août 1998) : 2952–57. http://dx.doi.org/10.1128/aem.64.8.2952-2957.1998.

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ABSTRACT Glutamine production with bacterial glutamine synthetase (GS) and the sugar-fermenting system of baker’s yeast for ATP regeneration was investigated by determining the product yield obtained with the energy source for ATP regeneration (i.e., glucose) for yeast fermentation. Fructose 1,6-bisphosphate was accumulated temporarily prior to the formation of glutamine in mixtures which consisted of dried yeast cells, GS, their substrate (glucose and glutamate and ammonia), inorganic phosphate, and cofactors. By an increase in the amounts of GS and inorganic phosphate, the amounts of glutamine formed increased to 19 to 54 g/liter, with a yield increase of 69 to 72% based on the energy source (glucose) for ATP regeneration. The analyses of sugar fermentation of the yeast in the glutamine-producing mixtures suggested that the apparent hydrolysis of ATP by a futile cycle(s) at the early stage of glycolysis in the yeast cells reduces the efficiency of ATP utilization. Inorganic phosphate inhibits phosphatase(s) and thus improves glutamine yield. However, the analyses of GS activity in the glutamine-producing mixtures suggested that the higher concentration of inorganic phosphate as well as the limited amount of ATP-ADP caused the low reactivity of GS in the glutamine-producing mixtures. A result suggestive of improved glutamine yield under the conditions with lower concentrations of inorganic phosphate was obtained by using a yeast mutant strain that had low assimilating ability for glycerol and ethanol. In the mutant, the activity of the enzymes involved in gluconeogenesis, especially fructose 1,6-bisphosphatase, was lower than that in the wild-type strain.

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Verkouteren, Jennifer R., Eric S. Windsor, Joseph M. Conny, Robert L. Perkins et J. Todd Ennis. « Analysis of kaolinite/chrysotile mixtures by ashing and x-ray diffraction ». Powder Diffraction 17, n^o 3 (septembre 2002) : 196–201. http://dx.doi.org/10.1154/1.1481038.

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A simple ashing procedure for a mixture containing kaolinite and chrysotile is described that converts kaolinite to amorphous metakaolinite while retaining the diffraction intensity of chrysotile. This ashing procedure removes the X-ray diffraction (XRD) pattern overlap between kaolinite and chrysotile that can interfere with the analysis of even high concentrations of chrysotile. Samples are ashed at 460 °C in a muffle furnace for 40 h to completely convert kaolinite to metakaolinite. The complete conversion of 1 g of kaolinite under these conditions was determined for two standard kaolinite samples from Georgia, KGa-1 and KGa-2. Two of the most common types of commercial chrysotile, long-fiber Canadian and short-fiber Californian chrysotile, are demonstrated to retain diffraction intensity after ashing at 460 °C. Both chrysotile samples have the same integrated intensity for the (002) reflection prior to ashing, although the peak breadths for the two samples are quite different. Ashing at 480 and 500 °C reduces the diffraction intensities of both chrysotile samples by 15%, and broadens the peaks by approximately 3%. Using the prescribed ashing procedure and x-ray diffraction with an internal corundum standard, two kaolinite-bearing building materials containing chrysotile near 0.01 mass fraction were analyzed. The ashing procedure has additional advantages in reducing some samples to powders and removing volatile components, thereby eliminating some sample preparation procedures and concentrating any chrysotile present in the sample. The removal of volatile components improves the sensitivity of XRD analysis to concentrations below 0.01 mass fraction chrysotile.

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Micinski, S., R. G. Scarborough, F. D. Forrester et J. B. Graves. « Efficacy of Selected Insecticide Mixtures for Bollworm and Tobacco Budworm Control, 1997 ». Arthropod Management Tests 23, n^o 1 (1 janvier 1998) : 239–41. http://dx.doi.org/10.1093/amt/23.1.239a.

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Abstract Thirteen treatments were evaluated at the Red River Research Station, Bossier City, LA, to determine their efficacy in controlling the bollworm/tobacco budworm (BW/TBW) complex on cotton. Plots were planted 9 May and were 4 rows X 100 ft on 40-inch centers. All plots had Temik 15 G (0.5 lb (AI)/acre) applied in-furrow at planting. The experimental design was a RCB with 4 replications. Prior to trial initiation, plots were oversprayed for cutworms on 6 Jun (Karate 1 EC at 0.025 lb (AI)/acre); boll weevils on 9, 13, 18 Jun and 3 Jul (Vydate C-LV at 0.25 lb (AI)/acre); BW/TBW on 27 Jun (Baythroid 2 EC at 0.03 lb (AI)/acre), and 11 Jul (Karate 1 EC at 0.03 lb (AI)/acre); and for aphids on 17 Jul (Provado 1.6°F at 0.047 lb (AI)/acre). Test materials were applied with a high-clearance sprayer equipped with a CO2 system for spraying small plots. Insecticide treatments were applied on 15, 22, 29 Jul, 5 and 14 Aug in 5.9 gpa at 60 psi with TX-3 hollow-cone nozzles spaced 20 inches apart (2 nozzles/row). Infestations of BW and TBW larvae and square damage were monitored on 18, 25 Jul, 1 and 11 Aug by examining 25 squares/plot. Following the trial, all plots were oversprayed for BW/TBW on 22 Aug with Karate 1 EC plus Curacron 8 EC at 0.028 + 0.75 lb (AI)/acre. Boll weevil eradication sprays with weekly applications of ULV Malathion (12 oz product/acre) were begun the week of 18 Aug. Yields were determined by mechanically harvesting the center 2 rows of each plot on 7 Oct.

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Zachariadis, George, et Efrosini Sahanidou. « Analytical performance of a fast multi-element method for titanium and trace elements determination in cosmetics and pharmaceuticals by ICP-AES ». Open Chemistry 9, n^o 2 (1 avril 2011) : 213–17. http://dx.doi.org/10.2478/s11532-010-0149-1.

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AbstractA multi-element analytical method based on inductively coupled plasma atomic emission spectrometry (ICP-AES) was developed for trace elements in pharmaceutical tablets and cosmetics. Titanium was also included in the analytes since it is widely used in pharmaceuticals. Critical ICP conditions, like RF incident power, argon gas flow rate and nebulizer sample uptake flow rate were optimized. The most sensitive spectral line of each analyte was selected as optimum for further study. Detection limits in the low µg g−1 range were obtained. Prior to chemical analysis, the samples were decomposed by acid digestion, using various mixtures of HCl, HNO3 and HF. Yttrium was used as a suitable internal standard in order to correct for possible matrix effects. The method was applied to the analysis of six different pharmaceutical products (anti-biotic, anti-inflammatory, anti-hypertensive) in the form of tablets with film coating and also three cosmetic products like hair and face masks.

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García-Gallego, M., H. Akharbach et M. de la Higuera. « Effects of dietary lipid composition on growth, food utilization and body composition of European eel (Anguilla anguilla) ». Animal Science 69, n^o 1 (août 1999) : 157–65. http://dx.doi.org/10.1017/s1357729800051195.

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AbstractSix experimental diets with similar contents of macronutrients (450, 300 and 70 g/kg dry matter of protein, carbohydrate and fat, respectively) and, therefore, total energy, hut differing in the composition of lipid component, were each given to three replicate groups of European eel. Different fat mixtures were used to formulate diets with different levels of fatty acids considered as essential for fish: linoleic (18: 2n6), linolenic (18: ЗпЗ) and highly unsaturated fatty acid (HUFA)n3, mainly EPA (20: 5n3) and DHA (22: 6n3). One tested diet contained low levels of all the three components, three diets had a high level of each one of these, the fifth diet contained high levels of both 18C fatty acids and, finally, a sixth diet incorporated simultaneously high amounts of 18: 2n6 and (HUFA)nЗ.Dietary lipid composition did not significantly affect food intake or protein and fat apparent digestibility. However, growth and food efficiency were the best with the diet containing approximately 5 g/kg of both linoleic and linolenic acids. Although all groups increased their body fat content over the experiment, the fatty acid composition of total muscle lipids was rather insensitive to lipid dietary composition, perhaps due to the high body fat content of the eels prior to the experiment.

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Stanton, Thad B., et Samuel B. Humphrey. « Persistence of Antibiotic Resistance : Evaluation of a Probiotic Approach Using Antibiotic-Sensitive Megasphaera elsdenii Strains To Prevent Colonization of Swine by Antibiotic-Resistant Strains ». Applied and Environmental Microbiology 77, n^o 20 (5 août 2011) : 7158–66. http://dx.doi.org/10.1128/aem.00647-11.

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ABSTRACTMegasphaera elsdeniiis a lactate-fermenting, obligately anaerobic bacterium commonly present in the gastrointestinal tracts of mammals, including humans. SwineM. elsdeniistrains were previously shown to have high levels of tetracycline resistance (MIC=64 to >256 μg/ml) and to carry mosaic (recombinant) tetracycline resistance genes. Baby pigs inherit intestinal microbiota from the mother sow. In these investigations we addressed two questions. When doM. elsdeniistrains from the sow colonize baby pigs? Can five antibiotic-sensitiveM. elsdeniistrains administered intragastrically to newborn pigs affect natural colonization of the piglets by antibiotic-resistant (AR)M. elsdeniistrains from the mother?M. elsdeniinatural colonization of newborn pigs was undetectable (<104CFU/g [wet weight] of feces) prior to weaning (20 days after birth). After weaning, all pigs became colonized (4 × 105to 2 × 108CFU/g feces). In a separate study, 61% (76/125) ofM. elsdeniiisolates from a gravid sow never exposed to antibiotics were resistant to chlortetracycline, ampicillin, or tylosin. The inoculation of the sow's offspring with mixtures ofM. elsdeniiantibiotic-sensitive strains prevented colonization of the offspring by maternal AR strains until at least 11 days postweaning. At 25 and 53 days postweaning, however, AR strains predominated. Antibiotic susceptibility phenotypes and single nucleotide polymorphism (SNP)-based identities ofM. elsdeniiisolated from sow and offspring were unexpectedly diverse. These results suggest that dosing newborn piglets withM. elsdeniiantibiotic-sensitive strains delays but does not prevent colonization by maternal resistant strains.M. elsdeniisubspecies diversity offers an explanation for the persistence of resistant strains in the absence of antibiotic selection.

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Manshor, Hanisah, Abdul Wahid Ramli, Ahmad Zahirani Ahmad Azhar, Ezzat Chan Abdullah et Zainal Arifin Ahmad. « Effect of Cr₂O₃-TiO₂ Addition on the Physical Properties of Zirconia Toughened Alumina ». Materials Science Forum 840 (janvier 2016) : 34–38. http://dx.doi.org/10.4028/www.scientific.net/msf.840.34.

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Zirconia toughened alumina (ZTA) has good mechanical properties and widely used in cutting insert application. Although the ZTA is well known of its good mechanical properties, its still can be improved in order to produce better properties. It can be done by adding additives as reinforcement such as magnesium oxide (MgO), cerium oxide (CeO), titania (TiO2) and chromia (Cr2O3). The effect of TiO2-Cr2O3 addition on the physical properties of ZTA were investigated in this study. The composition of TiO2 was varied from 0 wt% to 3.5 wt% while Cr2O3 was fixed at 5 wt%. The starting powder materials were mixed by wet mixing for 30 minutes in acetone. Then the powder mixtures were hydraulically pressed at 260 MPa. The green pellets were sintered at 1600°C for 1 hour using an electrical furnace in presureless condition. The results were characterized by XRD, density, and also Vickers hardness. The ZTA-Cr2O3-TiO2 ceramic composite achieved the highest density of 4.1 g/cm3 and Vickers hardness of 1919 HV prior to the addition of 2.0 wt% TiO2. Therefore, it can be decisively concluded that the addition of Cr2O3-TiO2 does affected the properties of ZTA.

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Komaikul, Jukrapun, Supachoke Mangmool, Waraporn Putalun et Tharita Kitisripanya. « Preparation of Readily-to-Use Stilbenoids Extract from Morus alba Callus Using a Natural Deep Eutectic Solvent ». Cosmetics 8, n^o 3 (19 septembre 2021) : 91. http://dx.doi.org/10.3390/cosmetics8030091.

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The consumer and cosmetic industries have recently placed a greater emphasis on ecofriendly solvents for botanical extraction, including natural deep eutectic solvents (NADES). In this study, NADES were prepared for Morus alba callus extraction. The efficiency of extraction from the NADES and methanol was investigated by comparison of the stilbenoids yield and anti-melanogenesis activity. Prior to testing the irritability of a suitable NADES on the reconstructed human epidermis (RhE), the effect of the selected NADES on stilbenoids stability was determined. The results showed that the highest yields of stilbenoids were obtained from choline chloride-glycerol mixtures (Ch1G2) and methanol extracts, with no significant difference in yields (5.06 ± 0.05 and 6.32 ± 0.40 mg/g callus dry weight, respectively). The NADES extracts of M. alba callus showed comparable anti-melanogenesis activity compared to methanol. In term of stability, stilbenoids in Ch1G2 remained stable after six months of storage at 4 °C except resveratrol. Furthermore, Ch1G2 had no irritation effect on RhE. Thus, based on the findings of this study, Ch1G2 is an intriguing green solvent alternative for the extraction of M. alba callus and may be advantageous for the preparation of skin-lightening cosmetics.

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Young, John K., Donghui Li, Matthew C. Abramowitz et Trudy G. Morrison. « Interaction of Peptides with Sequences from the Newcastle Disease Virus Fusion Protein Heptad Repeat Regions ». Journal of Virology 73, n^o 7 (1 juillet 1999) : 5945–56. http://dx.doi.org/10.1128/jvi.73.7.5945-5956.1999.

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ABSTRACT Typical of many viral fusion proteins, the sequence of the Newcastle disease virus (NDV) fusion protein has several heptad repeat regions. One, HR1, is located just carboxyl terminal to the fusion peptide, while the other, HR2, is located adjacent to the transmembrane domain. The structure and function of a synthetic peptide with a sequence from the region of the NDV HR1 region (amino acids 150 to 173) were characterized. The peptide inhibited fusion with a half-maximal concentration of approximately 2 μM; however, inhibition was observed only if the peptide was added prior to protease activation of the fusion protein. This inhibition was virus specific since the peptide had minimal effect on fusion directed by the Sendai virus glycoproteins. To explore the mechanism of action, the potential HR1 peptide interaction with a previously characterized fusion inhibitory peptide with a sequence from the HR2 domain (J. K. Young, R. P. Hicks, G. E. Wright, and T. G. Morrison, Virology 238:291–304, 1997) was characterized. The results demonstrated an interaction between the two peptides both functionally and directly. First, while the individual peptides each inhibit fusion, equimolar mixtures of the two peptides had minimal effect on fusion, suggesting that the two peptides form a complex preventing their interaction with a target protein. Second, an HR2 peptide covalently linked with biotin was found to bind specifically to HR1 peptide in a Western blot. The structure of the HR1 peptide was analyzed by nuclear magnetic resonance spectroscopy and found to be an α helix.

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Danko, Mikołaj, Aleksandra Żyła-Pawlak, Janusz Książyk, Katarzyna Olszewska-Durkacz, Marta Sibilska, Joanna Żydak et Katarzyna Popińska. « A Retrospective Analysis of the Effect of Combination of Pure Fish Oil with Third Generation Lipid Emulsion on Liver Function in Children on Long-Term Parenteral Nutrition ». Nutrients 11, n^o 10 (17 octobre 2019) : 2495. http://dx.doi.org/10.3390/nu11102495.

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Background: Deterioration of liver function, or intestinal failure-associated liver disease, is often observed in long-term parenterally fed children. Fish oil-based intravenous lipids have been reported to play a role in the prevention and treatment of intestinal failure associated liver disease. Methods: This retrospective analysis included 40 pediatric patients, (20 male and 20 female), median age 38 months (range 1.5–200 months) on long-term (≥1 month) parenteral nutrition who received the parenteral mixtures containing a combination of a third-generation lipid emulsion and pure fish oil because of laboratory liver function abnormalities. The total dose of fish oil from both emulsions for each patient exceeded 0.5 g/kg/day. Data from visits in an outpatient clinic were retrospectively analyzed using the Wilcoxon test, Mann-Whitney test, and Spearman correlation test. Results: The median time of therapy was 149 days (range 28–418 days). There was a decrease of median total and direct (conjugated) bilirubin concentration from 22.23 µmol/L (range 3.42–243 µmol/L) to 10.26 µmol/L (range 3.42–180.58 µmol/L; p < 0.005) and 8.55 (range 1.71–212.04 µmol/L) to 6.84 µmol/L (range 1.71–150.48 µmol/L; p < 0.007) respectively. A significant decrease in median alanine aminotransferase, aspartate aminotransferase and gamma-glutamyl transferase was also observed. In 11 patients bilirubin concentrations increased or remained unchanged. When compared to the patients who responded to the combination therapy, the patients who did not respond received parenteral nutrition for a longer time prior to the start of the therapy (51 vs. 30 months; p < 0.05). Conclusions: The mixture of an intravenous lipid emulsion containing soybean oil, medium-chain triglycerides, olive oil, and fish oil with the addition of pure fish oil emulsion may be helpful in the treatment of liver complications in children on long-term parenteral nutrition.

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Liang, Feng, Rui Paulo, German Molina, Merlise A. Clyde et Jim O. Berger. « Mixtures of g Priors for Bayesian Variable Selection ». Journal of the American Statistical Association 103, n^o 481 (1 mars 2008) : 410–23. http://dx.doi.org/10.1198/016214507000001337.

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Li, Yingbo, et Merlise A. Clyde. « Mixtures of g-Priors in Generalized Linear Models ». Journal of the American Statistical Association 113, n^o 524 (2 octobre 2018) : 1828–45. http://dx.doi.org/10.1080/01621459.2018.1469992.

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Dauer, Katharina, et Karl G. Wagner. « Micro-Scale Vacuum Compression Molding as a Predictive Screening Tool of Protein Integrity for Potential Hot-Melt Extrusion Processes ». Pharmaceutics 15, n^o 3 (22 février 2023) : 723. http://dx.doi.org/10.3390/pharmaceutics15030723.

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Hot-melt extrusion (HME) is used for the production of solid protein formulations mainly for two reasons: increased protein stability in solid state and/or long-term release systems (e.g., protein-loaded implants). However, HME requires considerable amounts of material even at small-scale (>2 g batch size). In this study, we introduced vacuum compression molding (VCM) as a predictive screening tool of protein stability for potential HME processing. The focus was to identify appropriate polymeric matrices prior to extrusion and evaluation of protein stability after thermal stress using only a few milligrams of protein. The protein stability of lysozyme, BSA, and human insulin embedded in PEG 20,000, PLGA, or EVA by VCM was investigated by DSC, FT-IR, and SEC. The results from the protein-loaded discs provided important insights into the solid-state stabilizing mechanisms of protein candidates. We demonstrated the successful application of VCM for a set of proteins and polymers, showing, in particular, a high potential for EVA as a polymeric matrix for solid-state stabilization of proteins and the production of extended-release dosage forms. Stable protein-polymer mixtures with sufficient protein stability after VCM could be then introduced to a combination of thermal and shear stress by HME and further investigated with regard to their process-related protein stability.

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Asohan, Anusha Wei, Rokiah Hashim, Ku Marsilla Ku Ishak, Zuratul Ain Abdul Hamid, Nurshafiqah Jasme et Yazmin Bustami. « Preparation and Characterisation of Cellulose Nanocrystal/Alginate/Polyethylene Glycol Diacrylate (CNC/Alg/PEGDA) Hydrogel Using Double Network Crosslinking Technique for Bioprinting Application ». Applied Sciences 12, n^o 2 (13 janvier 2022) : 771. http://dx.doi.org/10.3390/app12020771.

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In this study, we aimed to prepare and characterise hydrogel formulations using cellulose nanocrystals (CNCs), alginate (Alg), and polyethylene glycol diacrylate (PEGDA). The CNC/Alg/PEGDA formulations were formed using a double network crosslinking approach. Firstly, CNC was extracted from oil palm trunk, and the size and morphology of the CNCs were characterised using TEM analysis. Secondly, different formulations were prepared using CNCs, Alg, and PEGDA. The mixtures were crosslinked with Ca2+ ions and manually extruded using a syringe before being subjected to UV irradiation at 365 nm. The shear-thinning properties of the formulations were tested prior to any crosslinking, while the determination of storage and loss modulus was conducted post extrusion after the Ca2+ ion crosslink using a rheometer. For the analysis of swelling behaviour, the constructs treated with UV were immersed in PBS solution (pH 7.4) for 48 h. The morphology of the UV crosslinked construct was analysed using SEM imaging. The extracted CNC exhibited rod-like structures with an average diameter and length of around 7 ± 2.4 and 113 ± 20.7 nm, respectively. Almost all CNC/Alg/PEGDA formulations (pre-gel formulation) displayed shear-thinning behaviour with the power-law index η < 1, and the behaviour was more prominent in the 1% [w/v] Alg formulations. The CNC/Alg/PEGDA with 2.5% and 4% [w/v] Alg displayed a storage modulus dominance over loss modulus (G′ > G″) which suggests good shape fidelity. After the hydrogel constructs were subjected to UV treatment at 365 nm, only the F8 construct [4% CNC: 4% Alg: 40% PEGDA] demonstrated tough and flexible characteristics that possibly mimic the native articular cartilage property due to a similar water content percentage (79.5%). In addition, the small swelling ratio of 4.877 might contribute to a minimal change of the 3D construct’s geometry. The hydrogel revealed a rough and wavy surface, and the pore size ranged from 3 to 20 µm. Overall, the presence of CNCs in the double network hydrogel demonstrated importance and showed positive effects towards the fabrication of a potentially ideal 3D bioprinted scaffold.

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Tuzimski, Tomasz, et Szymon Szubartowski. « Method Development for Selected Bisphenols Analysis in Sweetened Condensed Milk from a Can and Breast Milk Samples by HPLC–DAD and HPLC-QqQ-MS : Comparison of Sorbents (Z-SEP, Z-SEP Plus, PSA, C18, Chitin and EMR-Lipid) for Clean-Up of QuEChERS Extract ». Molecules 24, n^o 11 (1 juin 2019) : 2093. http://dx.doi.org/10.3390/molecules24112093.

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Background: Identification and quantitative determination of analytes released from the packaging material is undoubtedly a difficult and tricky task, requiring the chemical analyst to develop an individual approach to obtain reliable analytical information. Unfortunately, it is still challenging for scientists to determine bisphenols at trace or even ultra-trace levels in samples characterized by a very complex, and often variable, matrix composition. Objective: Optimization and application of QuEChERS/d-SPE coupled with HPLC-DAD (and LC-QqQ-MS) method for the simultaneous determination of bisphenols (A, S, F, B, BADGE and derivatives) in milk samples from a can and breast milk samples have been performed. Methods: Concerning the analysis of unconjugated analytes, after the thawing and shaking the sample (5 mL breast milk or 10 mL milk samples from a can), it was transferred into a 50 mL polypropylene centrifuge tube. For the analysis of the total amount of analytes, prior to the extraction with acetonitrile, a deconjugation step was implemented in a tube by adding to sample, the an Isotopically Labelled Internal Standard (IS) solution (50 ng/mL) and 1 mL of the enzymatic solution with the β-Glucuronidase (3500 U/mL). The mix was homogenized and incubated for 16–18 h at 37 °C. Next, 10 mL of acetonitrile, and a QuEChERS salt packet (4 g anhydrous MgSO4, 1 g NaCl) were added. After shaking and centrifugation, the total acetonitrile layer was isolated in a polypropylene tube evaporate to dryness, and reconstitute in 1.2 mL acetonitrile. During d-SPE step the extract was transferred into a 15 mL polypropylene tube with Z-Sep and primary secondary amine (PSA). Next, shake the tube, store in fridge, and centrifuge for 15 min. The acetonitrile supernatant was obtained with a pipette and evaporated to dryness. Mixture MeOH: water (20:80, v/v) were added to the dry residue and the extract was reconstitute in 200 μL and analyzed by HPLC-DAD and HPLC–QqQ-MS equipment. Conclusion: Six different salts during d-SPE step were evaluated such as: zirconium dioxide-based sorbent (Z-Sep, Z-Sep Plus), primary secondary amine (PSA), octadecyl (C18), EMR-Lipid, Chitin and also their mixtures. Negligible matrix interference was observed for most of the analytes due to application of Z-Sep and PSA in dispersive-solid phase extraction clean-up step. Extraction of target analytes was performed using QuEChERS/d-SPE cleanup, and presents good performance for selected analytes with recoveries in the range of 15–103% and relative standard deviations (RSD) less than 10% in breast milk samples.

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KIM, JIN KYUNG, ELAINE M. D'SA, MARK A. HARRISON, JUDY A. HARRISON et ELIZABETH L. ANDRESS. « Listeria monocytogenes Survival in Refrigerator Dill Pickles ». Journal of Food Protection 68, n^o 11 (1 novembre 2005) : 2356–61. http://dx.doi.org/10.4315/0362-028x-68.11.2356.

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Listeria monocytogenes can survive and grow in refrigerated foods with pH values of approximately 4.0 to 5.0 and salt concentrations of 3 to 4%. Home-fermented refrigerator dill pickles fit this description. Contamination of this product with L. monocytogenes could cause serious problems because these items are not heated prior to consumption. L. monocytogenes survival and growth patterns were investigated in refrigerator dill pickles at 1.3, 3.8, and 7.6% salt concentrations. Pickling cucumbers were dipped into an inoculum of L. monocytogenes, brine mixtures were added, and cucumbers were held at room temperature for 1 week and then refrigerated for up to 3 months. The pH, NaCl percentage, titratable acidity percentage, and total populations of Listeria and aerobic, psychrotrophic, and lactic acid bacteria were measured at the addition of brine, after 2, 4, and 7 days of storage at room temperature, and then weekly during refrigerated storage. The initial Listeria population was 5.4 to 5.6 log CFU/cm2 on cucumber surfaces and 3.9 to 4.6 log CFU/g internally. There was an approximate 0.3- to 1-log increase during room temperature fermentation followed by a population decline during refrigerator storage, with a greater decrease in the brines with the highest NaCl concentration. Up to 49 days, the internal tissue of pickles with 1.3, 3.8, or 7.6% salt concentrations were presumptively positive for L. monocytogenes by the enrichment method, and at 91 days the surfaces of such pickles were still positive for L. monocytogenes. Populations of total aerobes and lactic acid bacteria increased during room temperature storage and decreased gradually during refrigerated storage.

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Ley, Eduardo, et Mark F. J. Steel. « Mixtures of g-priors for Bayesian model averaging with economic applications ». Journal of Econometrics 171, n^o 2 (décembre 2012) : 251–66. http://dx.doi.org/10.1016/j.jeconom.2012.06.009.

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Sullivan, R. C., S. A. Guazzotti, D. A. Sodeman et K. A. Prather. « Direct observations of the atmospheric processing of Asian mineral dust ». Atmospheric Chemistry and Physics 7, n^o 5 (22 février 2007) : 1213–36. http://dx.doi.org/10.5194/acp-7-1213-2007.

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Abstract. The accumulation of secondary acids and ammonium on individual mineral dust particles during ACE-Asia has been measured with an online single-particle mass spectrometer, the ATOFMS. Changes in the amounts of sulphate, nitrate, and chloride mixed with dust particles correlate with air masses from different source regions. The uptake of secondary acids depended on the individual dust particle mineralogy; high amounts of nitrate accumulated on calcium-rich dust while high amounts of sulphate accumulated on aluminosilicate-rich dust. Oxidation of S(IV) to S(VI) by iron in the aluminosilicate dust is a possible explanation for this enrichment of sulphate, which has important consequences for the fertilization of remote oceans by soluble iron. This study shows the segregation of sulphate from nitrate and chloride in individual aged dust particles for the first time. A transport and aging timeline provides an explanation for the observed segregation. Our data suggests that sulphate became mixed with the dust first. This implies that the transport pathway is more important than the reaction kinetics in determining which species accumulate on mineral dust. Early in the study, dust particles in volcanically influenced air masses were mixed predominately with sulphate. Dust mixed with chloride then dominated over sulphate and nitrate when a major dust front reached the R. V. Ronald Brown. We hypothesize that the rapid increase in chloride on dust was due to mixing with HCl(g) released from acidified sea salt particles induced by heterogeneous reaction with volcanic SO2(g), prior to the arrival of the dust front. The amount of ammonium mixed with dust correlated strongly with the total amount of secondary acid reaction products in the dust. Submicron dust and ammonium sulphate were internally mixed, contrary to frequent reports that they exist as external mixtures. The size distribution of the mixing state of dust with these secondary species validates previous mechanisms of the atmospheric processing of dust and generally agrees with simulated aerosol chemistry from the STEM-2K3 model. This series of novel results has important implications for improving the treatment of dust in global chemistry models and highlights a number of key processes that merit further investigation through laboratory and field studies.

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Rahayu, Endang Sri, Tjokorde Walmiki Samadhi, Subagjo et Melia Laniwati Gunawan. « Development of Hydrocracking Catalyst Support from Kaolin of Indonesian Origin ». Advanced Materials Research 896 (février 2014) : 532–36. http://dx.doi.org/10.4028/www.scientific.net/amr.896.532.

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The global shift of petroleum refinery towards heavier crude oils means an increasing demand of hydrocracking catalysts. This work studies the conversion of a kaolin originating from the Bangka island in Indonesia into a hydrocracking catalyst support consisting of zeolite-Y and amorphous alumina-silica phases. After a beneficiation process combining controlled settling and adsorption of the kaolin suspension in water with the addition of 125 ppm of 0.01% polyacrylamide solution as flocculant and 156 ppm of 0.1% calcium chloride solution as the adsorbent, the kaolinite phase content is increased from 63.6 to 74.3 %-mass. After spray drying, the kaolin is calcined at three temperatures for 2 hours each, producing calcined kaolin phases K700Cat 700 °C, K1013at 1013 °C, and K1050Cat 1050 °C. Temperatures of calcination for obtaining calcined kaolin phases is determined based on result of DSC/TGA. Synthesis of zeolite-Y is done by mixing varying proportions of these three calcined kaolin products, and zeolite-Y crystal seeds. These mixtures are aged at room temperature for 11 hours prior to reaction in a hydrothermal condition at 93 °C for 15-21 hours. The best calcined kaolin composition is found to be K700C: K1013C: K1050C= 10:85:5 (%-mass), resulting in a zeolite NaY purity of 86-88 % as characterized by X-ray diffraction (XRD), average ratio of SiO2/ Al2O3of 5.35, mean pore diameter of 23.1 Å, specific surface area of 186 m2/g, and a total pore volume of 0.107 mL/g as measured by N2adsorption. In a parallel manner, a series of amorphous silica-alumina (ASA) synthesis experiments is done to identify the best metakaolin calcination temperature and metakaoline activation pH. These are found to be 527 °C and 8.0, respectively, producing an ASA product with a 65 %-mass amorphous phase content as estimated by XRD data processing. To prepare the hydrocracking catalyst support, the zeolite NaY is added into the ASA-forming metakaolin sol at a pH of 8.0, aged for 8 hours at 50 °C. An initial morphological characterization of the obtained zeolite-ASA composite catalyst support suggests a good dispersion of the smaller zeolite NaY particles in the ASA microspheres.

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Links, Matthew G., Tim J. Dumonceaux, E. Luke McCarthy, Sean M. Hemmingsen, Edward Topp et Jennifer R. Town. « CaptureSeq : Hybridization-Based Enrichment of cpn60 Gene Fragments Reveals the Community Structures of Synthetic and Natural Microbial Ecosystems ». Microorganisms 9, n^o 4 (13 avril 2021) : 816. http://dx.doi.org/10.3390/microorganisms9040816.

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Background. The molecular profiling of complex microbial communities has become the basis for examining the relationship between the microbiome composition, structure and metabolic functions of those communities. Microbial community structure can be partially assessed with “universal” PCR targeting taxonomic or functional gene markers. Increasingly, shotgun metagenomic DNA sequencing is providing more quantitative insight into microbiomes. However, both amplicon-based and shotgun sequencing approaches have shortcomings that limit the ability to study microbiome dynamics. Methods. We present a novel, amplicon-free, hybridization-based method (CaptureSeq) for profiling complex microbial communities using probes based on the chaperonin-60 gene. Molecular profiles of a commercially available synthetic microbial community standard were compared using CaptureSeq, whole metagenome sequencing, and 16S universal target amplification. Profiles were also generated for natural ecosystems including antibiotic-amended soils, manure storage tanks, and an agricultural reservoir. Results. The CaptureSeq method generated a microbial profile that encompassed all of the bacteria and eukaryotes in the panel with greater reproducibility and more accurate representation of high G/C content microorganisms compared to 16S amplification. In the natural ecosystems, CaptureSeq provided a much greater depth of coverage and sensitivity of detection compared to shotgun sequencing without prior selection. The resulting community profiles provided quantitatively reliable information about all three domains of life (Bacteria, Archaea, and Eukarya) in the different ecosystems. The applications of CaptureSeq will facilitate accurate studies of host-microbiome interactions for environmental, crop, animal and human health. Conclusions: cpn60-based hybridization enriched for taxonomically informative DNA sequences from complex mixtures. In synthetic and natural microbial ecosystems, CaptureSeq provided sequences from prokaryotes and eukaryotes simultaneously, with quantitatively reliable read abundances. CaptureSeq provides an alternative to PCR amplification of taxonomic markers with deep community coverage while minimizing amplification biases.

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Tucki, Karol, Remigiusz Mruk, Olga Orynycz, Andrzej Wasiak, Katarzyna Botwińska et Arkadiusz Gola. « Simulation of the Operation of a Spark Ignition Engine Fueled with Various Biofuels and Its Contribution to Technology Management ». Sustainability 11, n^o 10 (16 mai 2019) : 2799. http://dx.doi.org/10.3390/su11102799.

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Economic progress, development of transport, production of new cars, production of more and more energy, and the combustion of fossil fuels are causing huge changes that are currently occurring in the environment. Ecological problems of the contemporary economy combined with perspectives of resources exhaustion, as well as the need to follow sustainable rules of living, require the search for new fuels. Fuels which can assure their availability and good environmental performance are needed for maintaining sustainable transportation. Knowledge about the behavior of various fuels is necessary for realistic methods of technology management in transportation means and the fuel industry. This paper describes biofuels that can be an addition to petrol or can exist as standalone fuels. A simulation was carried out on an urban vehicle and the tested fuels were petrol 95, ethanol, methanol, and dimethyl ether. For the selected engine a simulation corresponding to that of the New European Driving Cycle (NEDC) test was created using the Scilab package. Based on this simulation, values of carbon dioxide and water vapor emission were determined. The fuel demand for each fuel mixture and the amount of air for the fuels used were also calculated (and verified on the basis of laboratory tests). It was demonstrated that addition of biofuel decreases emission of carbon dioxide, simultaneously increasing emission of water vapor. Biofuel additive also caused an increase in fuel consumption. Unfortunately, in the New European Driving Cycle test being investigated, carbon dioxide emissions in all cases exceeded the permissible level of 130 g CO2/km, which is bad news in the context of the further tightening of norms and standards. The simulation tests confirmed that when using the start/stop system and applying specific additives, the carbon dioxide emission decreases and the consumption of mixtures with the activated start/stop system is smaller. The analyzed problems and results of this analysis become more important in light of the Worldwide Harmonized Light Duty Vehicles Test Procedure (WLTP) standard, which became binding from September 2018 and applies to the sale of cars that had been approved prior (in accordance with the New European Driving Cycle standard). Although the NEDC standard appears obsolete the computer model simulating this type of test will be necessary in many cases. It is, however, needed and possible to develop a similar simulation procedure for WLTP tests.

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Smagur, Andrzej, Iwona Mitrus, Sebastian Giebel, Agnieszka Ciomber, Joanna Gliwinska, Katarzyna Panczyniak, Maria Sadus-Wojciechowska et Jerzy Holowiecki. « Comparision Of Different Cryoprotective Solution - Albumin Vs Autologous Plasma - Its Effect On Cell Recovery and Clonogenic Potential Of Cryopreserved Peripheral Blood Hematopoietic Stem and Progenitor Cells ». Blood 122, n^o 21 (15 novembre 2013) : 4522. http://dx.doi.org/10.1182/blood.v122.21.4522.4522.

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Background Peripheral blood is a preferable source of hematopoietic stem and progenitor cells (HSPCs) used for autologous transplantation. HSPCs are mobilized to peripheral blood and collected by leukapheresis. Prior to cryopreservation the cells need to be processed including the addition of cryoprotective mixture as dimethyl sulfoxide (DMSO) prediluted in human serum albumin solution (HSAS). In Europe there is no commercially available albumin manufactured in packs with tubing which would enable the use of sterile tubing welder. Alternatively cryoprotective solution can be prepared using autologous plasma (AP) obtained during the same leukapheresis, allowing for the preparation of HSPCs in a completely closed system and hence to reduce the risk of contamination. The goal of our study was to test if the HSAS may be replaced by autologous plasma without negative impact on cell recovery and clonogenicity. Methods Samples were prospectively collected from 18 patients with multiple myeloma (n=13) and lymphomas (n=5) mobilized with chemotherapy combined with G-CSF. Small volumes (1.5 ml) of cell suspensions obtained from the leukapheresis products were divided into 2 parts (0,5ml) placed in separate small vials, each containing different cryoprotective mixture - 5% HSAS or AP with a final 7.5% DMSO concentration. The final volume of cell suspensions equaling 1 ml, the cell concentration (0.7–1.5 × 108 /ml). The cells were frozen in IceCube, using a computer controlled cooling program and stored in liquid nitrogen for 2 - 4 months. Concentration of total protein and individual electrophoretic fractions of plasma proteins were measured. The quality of cryoprotective mixtures was evaluated by cell recovery and clonogenic potential. The recovery was determined by comparing number of living cells before and after cryopreservation, using trypan blue staining. Clonogenic potential was carried out by colony forming unit (CFU) assays. Depending on CD34+ percentage, 5-40 × 103 living cells were plated (in triplicates) in MethoCult medium and cultured for 14 days. Results The median recovery of nucleated cells for AP was 68.3% (range 40.6-96.1) and was similar to HSAS 68.5%, (41.7-100); (p=0.3; Wilcoxon matched pairs test). The number of CFUs calculated per 100 000 cryopreserved cells did not differ significantly between tested cryoprotective mixture: 187.3 (11.3-806.3) for albumin, 130.5 (15-924.2) for autologous plasma (p=0.5; Wilcoxon matched pairs test). No significant differences were observed when the number of specific types of CFUs were compared. Neither total protein nor albumin concentration of plasma correlated with the clonogenic potential of the leukapheresis product cryopreserved in AP when samples from patients with higher concentration than median were compared with the other (Mann-Whitney U test). Between January and July 2013 more than 50 successful transplants of autologous HSPCs cryopreserved with 7.5% DMSO prediluted in autologous plasma were performed in our Department. Conclusions Commercially available human serum albumin can be replaced by autologous plasma in procedure of HSPCs cryopreservation. The use of autologous plasma for cryoprotective mixture preparation does not appear to negatively affect cell recovery and clonogenic potential of leukapheresis product. The advantage of such solution is possibility of HSPCs preparation in closed system to reduce risk of auto-HSCT product contamination to the minimum. Disclosures: No relevant conflicts of interest to declare.

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Smagur, Andrzej, Iwona Mitrus, Sebastian Giebel, Maria Sadus-Wojciechowska, Jacek Najda, Tomasz Kruzel, Tomasz Czerw et al. « Effect of Various Concentrations of Dimethyl Sulfoxide (DMSO) on Cell Recovery and Clonogenic Potential of Cryopreserved Peripheral Blood Hematopoietic Progenitors ». Blood 118, n^o 21 (18 novembre 2011) : 1930. http://dx.doi.org/10.1182/blood.v118.21.1930.1930.

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Abstract Abstract 1930 BACKGROUND: Hematopoietic stem cells mobilized to peripheral blood and collected by leukapheresis are predominantly used for autologous transplantation. Prior to cryopreservation the cells need to be processed including the addition of DMSO (dimethyl sulfoxide), which enhance cell survival, but is potentially toxic to stem cell recipient. The most commonly used concentration of DMSO is 10%. The goal of our study was to test if the concentration may be reduced without negative impact on cell recovery and clonogenicity. METHODS: Samples were prospectively collected from 12 patients with lymphomas mobilized with chemotherapy combined with G-CSF. Small volumes (2–3 ml) of cell suspensions obtained from the leukapheresis product were divided into 4 parts placed in separate small vials, each containing different cryoprotective mixture - with 10%, 7.5%, 5% and 2.5% DMSO. The final volume of cell suspensions equaling 1 ml, the cell concentration (0.8–1 × 108 /ml) and the proportions of human albumin and plasma were the same in all vials. The cells were frozen in IceCube, using a computer controlled cooling program and stored in liquid nitrogen for 2 weeks – 4 months. The quality of cryoprotective mixtures was evaluated by cell recovery and clonogenic potential. The recovery was determined by comparing number of living cells before and after cryopreservation, using trypan blue staining. Clonogenic potential was carried out by colony forming unit (CFU) assays. Depending on CD34+ percentage, 5 or 10 × 103 living cells were plated (in triplicates) in medium MethoCult and cultured for 14 days. RESULTS: The median recovery of nucleated cells for 10% DMSO was 62.4% (range 41.2–86.8) and was significantly higher compared to 7.5% DMSO (54.9%, 41.2–89.1; p=0.04), 5% DMSO (49.2%, 28.1–69.8; p=0.002) and 2.5% DMSO (37.2%, 19.3–54.3; p=0.002). The number of CFUs calculated per 100 000 cryopreserved cells did not differ significantly according to DMSO concentration: 217 (14–1795) for 10% DMSO, 225 (27–2718) for 7.5% DMSO, 196 (26–2761) for 5% DMSO, and 178 (14–2208) for 2.5% DMSO. Neither cell recover nor clonogenic potential correlated with the percentage of CD34+ cells in the leukapheresis product. CONCLUSIONS: Reduction of DMSO concentration to equal or below 7.5% is associated with impaired recovery of nucleated cells after cryopreservation. However, it does not appear to negatively affect clonogenic potential of leukapheresis product, suggesting relative resistance of hematopoietic progenitor cells. Therefore, considering potential toxicity of DMSO to stem cell recipient, its lower concentrations may be clinically beneficial. This hypothesis requires prospective verification in a setting of autologous transplantation. Disclosures: No relevant conflicts of interest to declare.

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Alotaibi, Refah, Lamya A. Baharith, Ehab M. Almetwally, Mervat Khalifa, Indranil Ghosh et Hoda Rezk. « Statistical Inference on a Finite Mixture of Exponentiated Kumaraswamy-G Distributions with Progressive Type II Censoring Using Bladder Cancer Data ». Mathematics 10, n^o 15 (7 août 2022) : 2800. http://dx.doi.org/10.3390/math10152800.

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A new family of distributions called the mixture of the exponentiated Kumaraswamy-G (henceforth, in short, ExpKum-G) class is developed. We consider Weibull distribution as the baseline (G) distribution to propose and study this special sub-model, which we call the exponentiated Kumaraswamy Weibull distribution. Several useful statistical properties of the proposed ExpKum-G distribution are derived. Under the classical paradigm, we consider the maximum likelihood estimation under progressive type II censoring to estimate the model parameters. Under the Bayesian paradigm, independent gamma priors are proposed to estimate the model parameters under progressive type II censored samples, assuming several loss functions. A simulation study is carried out to illustrate the efficiency of the proposed estimation strategies under both classical and Bayesian paradigms, based on progressively type II censoring models. For illustrative purposes, a real data set is considered that exhibits that the proposed model in the new class provides a better fit than other types of finite mixtures of exponentiated Kumaraswamy-type models.

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El-Bardicy, Mohammad G., Hayam M. Lotfy, Mohammad A. El-Sayed et Mohammad F. El-Tarras. « Smart Stability-Indicating Spectrophotometric Methods for Determination of Binary Mixtures Without Prior Separation ». Journal of AOAC INTERNATIONAL 91, n^o 2 (1 mars 2008) : 299–310. http://dx.doi.org/10.1093/jaoac/91.2.299.

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Abstract Ratio subtraction and isosbestic point methods are 2 innovating spectrophotometric methods used to determine vincamine in the presence of its acid degradation product and a mixture of cinnarizine (CN) and nicergoline (NIC). Linear correlations were obtained in the concentration range from 840 g/mL for vincamine (I), 622 g/mL for CN (II), and 636 g/mL for NIC (III), with mean accuracies 99.72 0.917 for I, 99.91 0.703 for II, and 99.58 0.847 and 99.83 1.039 for III. The ratio subtraction method was utilized for the analysis of laboratory-prepared mixtures containing different ratios of vincamine and its degradation product, and it was valid in the presence of up to 80 degradation product. CN and NIC in synthetic mixtures were analyzed by the 2 proposed methods with the total content of the mixture determined at their respective isosbestic points of 270.2 and 235.8 nm, and the content of CN was determined by the ratio subtraction method. The proposed method was validated and found to be suitable as a stability-indicating assay method for vincamine in pharmaceutical formulations. The standard addition technique was applied to validate the results and to ensure the specificity of the proposed methods.

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Wang, Min. « Mixtures of $g$ -Priors for Analysis of Variance Models with a Diverging Number of Parameters ». Bayesian Analysis 12, n^o 2 (juin 2017) : 511–32. http://dx.doi.org/10.1214/16-ba1011.

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Adam, S. E. I., A. H. Al-Farhan et M. A. Al-Yahya. « Effect of Combined Citrullus Colocynthis and Rhazya Stricta Use in Najdi Sheep ». American Journal of Chinese Medicine 28, n^o 03n04 (janvier 2000) : 385–90. http://dx.doi.org/10.1142/s0192415x00000453.

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The effect of oral administration of 0.25 g/kg/day of Citrullus colocynthis fruits, 0.25 g/kg/day of Rhazya stricta leaves or mixture of the two plants at 0.25 g/kg/day of C. colocynthis fruits plus 0.25 g/kg/day of R. stricta leaves in Najdi sheep was examined. Oral administration of 0.25 g/kg/day of C. colocynthis fruits or 0.25 g/kg/day of R. stricta leaves for 42 days proved not fatal but that of the mixture of the two plants (0.25 g + 0.25 g/kg/day) proved fatal within 26 days with profuse diarrhea, dehydration, loss in condition, ataxia and recumbency, prior to death. These manifestations accompanied by enterohepatonephrotoxicity, gelatinization of the renal and epicardial fat and transudate in serous cavities were correlated with alterations in serum LDH and AST activities and concentrations of total protein, albumin, globulin, bilirubin, cholesterol and urea and hematology.

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Adam, S. E. I., M. A. Al-Yahya et A. H. Al-Farhan. « Toxicity of Nerium oleander and Rhazya stricta in Najdi Sheep : Hematologic and Clinicopathologic Alterations ». American Journal of Chinese Medicine 30, n^o 02n03 (janvier 2002) : 255–62. http://dx.doi.org/10.1142/s0192415x02000326.

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The toxic effects of oral administration of 0.25 g/kg Nerium oleander leaves, 0.25 g/kg Rhazya stricta leaves or their mixture at 0.25 g/kg N. oleander leaves plus 0.25 g/kg R. stricta leaves on Najdi sheep were investigated. Daily oral dosing of R. stricta leaves for 42 days was not fatal to sheep while single oral doses of either N. oleander leaves or the mixture with R. stricta leaves proved fatal to animals within 24 hours with dyspnea, grunting, salivation, grinding of the teeth, ruminal bloat, frequent urination, ataxia and recumbency prior to death. The main lesions were widespread congestion or hemorrhage, pulmonary cyanosis, emphysema, bronchotracheal froths, and hepatonephropathy. The clinical and pathological changes were correlated with alterations in serum LDH and AST activities and concentrations of cholesterol, bilirubin, urea, total protein, albumin, and globulin and hematological values.

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Blackshaw, Robert E. « Control of Downy Brome (Bromus tectorum) in Conservation Fallow Systems ». Weed Technology 5, n^o 3 (septembre 1991) : 557–62. http://dx.doi.org/10.1017/s0890037x00027329.

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Field studies were conducted to determine the most effective rate of several herbicides applied at various growth stages to control downy brome in conservation fallow programs. Downy brome growth stage affected the efficacy of all herbicides. All herbicides were less effective when application was delayed until the boot stage of downy brome. Fluazifop-P and sethoxydim must be applied prior to tillering to effectively control downy brome. Glyphosate, the commercial mixture of glyphosate plus 2,4-D, paraquat, and HOE-39866 consistently controlled downy brome up to the 3- to 5-tiller stage. Glyphosate at 180 to 200 g ha-1, paraquat at 250 to 300 g ha-1, and the commercial mixture of glyphosate plus 2,4-D at 600 to 660 g ha-1controlled downy brome 80 to 90%. The effective rates were lower than rates currently registered for downy brome control in western Canada, and thus there is potential for making conservation fallow programs more economical when downy brome is the predominant weed.

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Mukhopadhyay, Minerva, et Tapas Samanta. « A mixture of g-priors for variable selection when the number of regressors grows with the sample size ». TEST 26, n^o 2 (20 décembre 2016) : 377–404. http://dx.doi.org/10.1007/s11749-016-0516-0.

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Kumar, Beera Babu Srinivas, et Periyapattinam Srinivasaiah Satyanarayana. « A mixture of Noise Image Denoising using Sevenlets Wavelet Techniques ». Trends in Sciences 19, n^o 10 (13 mai 2022) : 4186. http://dx.doi.org/10.48048/tis.2022.4186.

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The noise has always been present in digital images when coding, image acquisition, transmission and processing steps has often corrupted by noise. Noise is challenging to confiscate from the digital images without the noise model’s prior information preserving edges. That is why the assessment of noise models is essential in the revise of image denoising techniques. A novel approach to improve the performance of an image’s quality and visual perception must be noise-free. The essential features like edge details should be retained as much as possible due to the increased traffic caused by multimedia information and digitized form of representation of images. This research articulates a brief general fundamental proposal of the noise model. The input image has debased with different noise probability density of Gaussian (G), Speckle (S), Salt and Pepper (SP) noise and a mixture of noise (G + S + SP). The Wavelet technique’s methodology using Sevenlets wavelet are Haar, Daubechies, Coiflets, Symlets, Discrete Meyer, Biorthogonal and Reverse Biorthogonal input Lena standard image has decomposed using Discrete Wavelet Transform (DWT). The decomposition process, as accomplished by discriminating the input image with lower and higher image coefficients. Filtering techniques are employed to deplete the noise present in an image. Hence the quantitative investigation of noise model at hard and soft thresholding is analyzed, improving image quality by increasing PSNR and decreasing MSE to have better performance. HIGHLIGHTS The images may be corrupted randomly in the transmission line; it is significant to retrieve exactly without loss of data; it is a challenging task. The images are examined with a different mixture of noises with corrupting at various percentage levels. In transmission channels the data will be corrupted, the primary aim is to retrieve actual data. For the testing purpose Gaussian (G), Speckle (S), and Salt & Pepper (SP) noise added to the Lena image have been corrupted and denoised. Denoising using methodology Discrete Wavelet Transform (DWT), to obtain better clarity image quality furthermore noise is filtered using Weiner and Median Filters. The mixture of noises of 0.1, 1, and 10 % density noise (G+S) (Gaussian (G) pulse Speckle (S)), G+S+SP (Gaussian (G) plus Speckle (S) pulse Salt & Pepper (SP)) added to the Lena image and denoised, have obtained improved denoised images comparing to previous research results.

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