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Baillargeon, Dany, Alexandre Coutant, Marie-Eve Carignan, Elyse Dionne e Mikaëlle Tourigny. "Confrontations et convergences éthiques entre marketing et information autour de la publicité native". Revue Communication & professionnalisation, n. 5 (5 dicembre 2017): 28–53. http://dx.doi.org/10.14428/rcompro.vi5.863.
Abstract (sommario):
La perméabilité de la division information/publicité dans les salles de rédaction fait récursivement l’objet de débats au sein de l’industrie journalistique. Mus par des logiques différentes, univers marketing et journalistique sont supposés se prémunir de toute influence mutuelle. L’arrivée des plateformes socio numériques, l’éclatement du modèle économique des médias d’information et l’irritation face à l’intrusion publicitaire et les stratégies de blocage encouragent de nouveaux chevauchements, dont la publicité native (PN). Les différentes justifications ou critiques de cette technique controversée constituent une entrée pour analyser le rapport à l’éthique des deux professions, journalisme et marketing. Cette communication propose d’interroger ce phénomène par une double analyse. D’abord en repérant dans le discours des professionnels du marketing et de l’information les différentes rationalités entourant l’utilisation, ou non, de la PN. Ces rationalités sont ensuite adossées aux codes, chartes et guides déontiques. Au final, nous arguons que les guides actuels sont insuffisants pour encadrer le bouleversement professionnel qu’engendre la PN, entre autres sous la force de tensions séculaires, mais fortement bousculées par des rationalités convergentes. Ce paradoxe semble se solder par l’arrivée d’un nouveau type de professionnel, le producteur de contenu. Nous ouvrons quelques pistes pour explorer plus avant cette transformation professionnelle.
Mots Clés : publicité native, journalisme, analyse de discours, éthique
The porousness of the information/advertising division in newsrooms is a recursive topic of debate in the journalism industry. With their distinct logics, the worlds of marketing and journalism are supposed to guard against any mutual influence, as enshrined in ethical codes and charters. But the rise of social media platforms, the fragmentation of the economic model of the news media, the irritation of advertising intrusion, and the ad blocking software are encouraging new overlaps, one being native advertising (NA). The various justifications or criticisms of this controversial technique constitute for us the entry point to analyze the ethics of both journalism and marketing in regard of NA. First, we identify, within the discourse of both marketing and information professionals, the different rationalities surrounding the use or non use of NA. These rationalities are then compared to codes, charters and deontic guides in use. In the end, we argue that the current guides are insufficient to frame the professional upheaval that NA generates, under the force of deep-rooted tensions, now strongly shaken by convergent economical rationalities. This paradox seems to result in the arrival of a new type of professional, the content producer. We open up some avenues to explore this professional transformation further.
Keywords: Ethics, deontology, native advertising, marketing, journalism
2
Lu, Chen, Jinhua Xu, Long Wang, Hongjie Wang, Biao He, Chongming Tian e Wangping Qian. "Analysis of the Influencing Factors of Crystalline Blockages in Mountain Tunnel Drainage Systems Based on Decision Analysis Methods". Applied Sciences 13, n. 6 (15 marzo 2023): 3721. http://dx.doi.org/10.3390/app13063721.
Abstract (sommario):
Crystalline blockages in mountain tunnel drainage systems are becoming a common environmental problem. Considering the lack of research on the influence degree of the factors affecting crystalline blockages in mountain tunnel drainage systems, this paper classified and evaluated the importance of relevant factors through decision analysis methods. Our purpose is to provide a comprehensive understanding of the primary factors causing crystalline blockages in tunnels. The influence factors are selected and categorized through a literature review, and then the influence factors are screened twice by the expert scoring method and the gray-whitening weighted function clustering method to eliminate the less important influence factors. Finally, the influence factors are evaluated systematically according to the hierarchical analysis method. The results indicate that the factors affecting the crystalline blockage of the drainage system can be divided into five categories: hydrology, geology, shotcrete materials, drainage facilities, and the cave environment. Among these factors, shotcrete materials are the key factors affecting the problem of crystalline blockages. Specifically, the density of shotcrete and the content of calcium in cement have a significant impact on the crystalline blockages, which have the following comprehensive weights: 0.221 and 0.152, respectively. Since the shotcrete materials are human controllable factors, they can be taken as the key research objects to solve the problem of crystalline blockages.
3
Kashcheev, I. D., A. B. Finkel’shteyn, A. E. Glyzina, A. A. Shefer, A. V. Shak e V. D. Silivanov. "Possibility of using unshaped thermal insulation of aluminum alloy castings". NOVYE OGNEUPORY (NEW REFRACTORIES), n. 9 (25 novembre 2022): 52–56. http://dx.doi.org/10.17073/1683-4518-2022-9-52-56.
Abstract (sommario):
The possibility of using diatomite from the Ilyinsky deposit as an unshaped thermal insulation for open risers of castings from aluminum alloys of different alloying systems: technical aluminum A5, AK7, AMg10, VAL10 has been studied. It was found that when the continuity of the oxide film on the surface of a diatomite particle is broken, an exchange reaction occurs with the formation of a silicon transition layer. Since silicon is wetted by aluminum, the diatomite particle sinks in the melt, forming a blockage. As a criterion for the continuity of the oxide film, it is proposed to use the Pilling‒Badworth factor of the alloy components. It has been shown that a high level of the Pilling‒Badworth factor, even at a low content of the component (~ 1 %), leads to the formation of blockages. Ill. 6. Ref. 12. Tab. 1.
4
Fayolle, Jacky, e Françoise Milewski. "L'offre devance la demande". Revue de l'OFCE 55, n. 4 (1 novembre 1995): 5–94. http://dx.doi.org/10.3917/reof.p1995.55n1.0005.
Abstract (sommario):
Résumé Après l'accélération prononcée de l'activité et du commerce mondiaux en 1994, le ralentissement intervenu depuis le début 1995 est largement généralisé au sein des pays de l'OCDE. Le manque de dynamisme de la consommation et le déficit de confiance des ménages en est un facteur général, même si cette caractéristique commune participe de phases différentes du cycle conjoncturel, selon les pays. Les pays anglo-saxons, spécialement les États-Unis, sont en voie de connaître une fin de cycle sans drame, prolongée par le recours au crédit à la consommation. Au Japon, la faiblesse de la consommation est la contrepartie d'une préférence exacerbée pour la liquidité et alimente le risque de spirale déflationniste qui menace ce pays. À partir de points de départ évidemment différents, la zone anglo-saxonne et le Japon ne devraient pas enregistrer des taux de croissance supérieurs à 2% en 1996 et ne seront pas des locomotives de la croissance mondiale. En Europe, le retour de comportements de précaution parmi les consommateurs peut handicaper la réalisation des projets d'investissement aujourd'hui formulés par les entreprises et s'opposer ainsi à la confirmation d'une expansion régularisée. Les déséquilibres dans le partage des revenus et le sentiment d'insécurité économique expliquent cet attentisme. Les disparités européennes, entre pays aux monnaies surévaluées et pays aux monnaies sous-évaluées ou en voie de l'être, contribuent aussi à geler la capacité d'expansion européenne. Dans les premiers pays, l'activité est entravée par le handicap de compétitivité ; dans les seconds, les résurgences inflationnistes et les réactions de la politique monétaire qu'elles suscitent pénalisent la demande interne. La normalisation de la situation monétaire, sur le front des taux de change, est ainsi nécessaire au retour de l'expansion européenne. Elle corrigerait les distorsions actuelles de compétitivité. Cette chronique de conjoncture fait l'hypothèse d'une telle normalisation, en particulier par une certain redressement du dollar sur l'horizon de prévision. La conjoncture allemande devrait contribuer à un dénouement positif du blocage européen en 1996. En Allemagne, le surcroît de revenus, après la généralisation des hausses salariales, paraît suffisant pour vaincre les réticences à consommer. Les exportateurs allemands bénéficieraient des achats de biens d'équipement par les industriels européens et de la poursuite de la reconstitution de leurs parts de marché. La politique monétaire allemande accompagnerait ce mouvement. La croissance allemande, après 2,5% en 1995, pourrait se rapprocher ainsi de 3% en 1996, sans pour autant atteindre ce chiffre. En France, la reprise a marqué une pause au premier semestre 1995, après l'emballement de 1994. Un environnement européen moins porteur et un contexte monétaire français nettement plus restrictif qu'anticipé en début d'année, ont sensiblement pesé sur l'activité. Le palier actuel débouche-t-il sur un retournement à la baisse ou bien un redémarrage ? Le pessimisme des entreprises n'a pas, pour le moment, conduit à une inflexion sensible des comportements de dépense, dans un sens restrictif : les embauches se développent, fussent-elles parfois à temps partiel et souvent à durée déterminée. Les salaires individuels s'accélèrent. Les investissements prévus n'ont pas été mis en cause. Les stocks, en revanche, ont pâti du retournement des anticipations. La logique de la prévision dépend crucialement de la consommation future des ménages. Davantage de revenus salariaux et de prestations soutiendraient la hausse du revenu global, malgré les prélèvements supplémentaires. Une reprise de la demande extérieure, dès le début de 1996, conforterait les exportations. La croissance de l'investissement des entreprises pourrait alors s'amplifier, aucun obstacle financier ne venant obérer les dépenses. En revanche, le contexte serait restrictif pour l'investissement et la consommation publics ; l'investissement en logements reculerait. Malgré une reprise de la formation des stocks, interrompue en 1995, la croissance du PIB serait de 2,5% seulement l'an prochain après 2,9% cette année. La reprise envisagée dépend des hypothèses de politique économique. La normalisation financière anticipée peut buter sur des tensions intra-européennes et accroître l'incertitude des entreprises. Un comportement plus prudent en matière d'embauchés et de politique salariale briserait le cheminement de la reprise. Enfin, les particuliers eux-mêmes finissent par être sensibles à la dévalorisation de leurs actifs, qu'ils soient immobiliers ou financiers. La croissance du PIB, bien que faible, permettrait une nette baisse du chômage : un contenu plus intense en emplois, un accent mis sur le traitement social et une moindre croissance de la population active y concourraient. Peu supérieure à la croissance du potentiel productif, la croissance du PIB ne comblerait pas le creux acquis durant les années précédentes : le niveau du potentiel ne serait pas atteint à l'horizon de la prévision. L'économie française resterait donc en sous-utilisation des capacités de production, avec toutes les pressions désinflationnistes que cela implique.
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Yang, Wei, Zhongyan Wang, Baosheng An, Yingying Chen, Chuanxi Zhao, Chenhui Li, Yongjie Wang et al. "Early warning system for ice collapses and river blockages in the Sedongpu Valley, southeastern Tibetan Plateau". Natural Hazards and Earth System Sciences 23, n. 9 (8 settembre 2023): 3015–29. http://dx.doi.org/10.5194/nhess-23-3015-2023.
Abstract (sommario):
Abstract. The Tibetan Plateau and its surroundings have recently experienced several catastrophic glacier-related disasters. It is of great scientific and practical significance to establish ground-based early warning systems (EWSs) to understand the processes and mechanisms of glacial disasters and warn against potential threats to downstream settlements and infrastructure. However, there are few sophisticated EWSs on the Tibetan Plateau. With the support of the Second Tibetan Plateau Scientific Expedition and Research Program (STPSER), an EWS was developed and implemented in the Sedongpu Valley, southeastern Tibetan Plateau, where repeated river blockages have occurred due to ice/rock collapse debris flow. The EWS collected datasets of optical/thermal videos/photos, geophone waveforms, water levels, and meteorological variables in this sparsely populated zone. It has successfully warned against three ice-rock collapse–debris flow–river blockage chain events, and seven small-scale ice-rock collapse–debris flow events. Meanwhile, it was found that the low-cost geophone can effectively indicate the occurrence and magnitude of ice/rock collapses by local thresholds, and water level observation is an efficient way to warn of river blockages. Our observations showed that there were no immediate meteorological triggers for the ice-rock collapses and associated debris flows. Several factors, such as the volume and location of the collapses and the percentage of ice content involved, influence the velocities of debris flows and the magnitude of river blockages. There are still two possible glaciers in the study area that are at risk of ice collapse. It is worth monitoring their dynamic changes using high-resolution satellite data and the ground-based EWS to safeguard the surrounding hydrological projects and infrastructure in this transboundary region.
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Dong, Wenting, Dong Zhang, Keliang Wang e Yue Qiu. "Investigation on degradation mechanism of polymer blockages in unconsolidated sandstone reservoirs". e-Polymers 20, n. 1 (2 marzo 2020): 55–60. http://dx.doi.org/10.1515/epoly-2020-0006.
Abstract (sommario):
AbstractPolymer flooding technology has shown satisfactorily acceptable performance in improving oil recovery from unconsolidated sandstone reservoirs. The adsorption of the polymer in the pore leads to the increase of injection pressure and the decrease of suction index, which affects the effect of polymer flooding. In this article, the water and oil content of polymer blockages, which are taken from Bohai Oilfield, are measured by weighing method. In addition, the synchronous thermal analyzer and Fourier transform infrared spectroscopy (FTIR) are used to evaluate the composition and functional groups of the blockage, respectively. Then the core flooding experiments are also utilized to assess the effect of polymer plugs on reservoir properties and optimize the best degradant formulation. The results of this investigation show that the polymer adsorption in core after polymer flooding is 0.0068 g, which results in a permeability damage rate of 74.8%. The degradation ability of the agent consisting of 1% oxidizer SA-HB and 10% HCl is the best, the viscosity of the system decreases from 501.7 to 468.5 mPa‧s.
7
Ruan, Zhuen, Yong Wang, Aixiang Wu, Shenghua Yin e Fei Jin. "A Theoretical Model for the Rake Blockage Mitigation in Deep Cone Thickener: A Case Study of Lead-Zinc Mine in China". Mathematical Problems in Engineering 2019 (22 gennaio 2019): 1–7. http://dx.doi.org/10.1155/2019/2130617.
Abstract (sommario):
Deep cone thickener (DCT) is key equipment in cemented paste backfill (CPB) technology. However, rake blockage occurs frequently in DCT during the dewatering process of the unclassified tailings being thickened from dilute slurry to thickened tailings or paste. Rake blockage has disastrous effects on the CPB operation. In order to investigate the influencing factors of rake blockage in DCT, a mathematical model of rake power in DCT was developed. In addition, stacking mud bed (made of thickened tailings) from the DCT in Huize lead-zinc mine (HLZM) in different rake blockage accidents was sampled and tested to investigate the effect of tailings characters on rake blockage. Results indicated that the concentration of the mud bed and the friction between the mud bed and the cone wall contributed to the rake blockage. The concentration and friction were influenced by the high content of coarse particles in the mud bed. Moreover, activating devices for bed mud, as the corrective and preventive action, were developed to prevent the rake blockage, which was valid in HLZM.
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Yao, Lei, Fangfang Ma, Jie Peng, Jianbo Zhang, Yangjun Zhang e Jianpeng Shi. "Analysis of the Failure Modes in the Polymer Electrolyte Fuel Cell Cold-Start Process—Anode Dehydration or Cathode Pore Blockage". Energies 13, n. 1 (4 gennaio 2020): 256. http://dx.doi.org/10.3390/en13010256.
Abstract (sommario):
In this study, the cold-start failure processes of a polymer electrolyte fuel cell have been investigated numerically for different initial membrane water content λ 0 and the startup current densities I 0 . The result shows that the failure of the cell cold-start process is mostly attributed to the anode dehydration when the cell operates with relatively large current density. However, the failure is dominated by the cathode pore blockage when the cell starts with relatively high initial membrane water content. Corresponding maps for the classification of startup failure modes are plotted on the λ 0 − I 0 plane with different startup temperatures. Three zones, including the anode dehydration, the cathode pore blockage, and the ambiguous region, can be observed. They can be distinguished with different startup failure mechanisms. The anode dehydration zone is expanded as the cell startup temperature drops due to the weakening of the membrane water back-diffusion ability. In the ambiguous region, the startup failure phenomena may be either anode dehydration or cathode pore blockage, which depends on the stochastic freezing process of the supercooled water.
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Jary, Marine, Christophe Borg, Olivier Bouché, Stéfano Kim, Thierry André e Jaafar Bennouna. "Traitements anti-angiogéniques dans le cancer colorectal métastatique : peut-on envisager un blocage continu de l’angiogenèse ?" Bulletin du Cancer 102, n. 9 (settembre 2015): 758–71. http://dx.doi.org/10.1016/j.bulcan.2015.05.002.
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Johnston, R. N., J. Feder, A. B. Hill, S. W. Sherwood e R. T. Schimke. "Transient inhibition of DNA synthesis results in increased dihydrofolate reductase synthesis and subsequent increased DNA content per cell". Molecular and Cellular Biology 6, n. 10 (ottobre 1986): 3373–81. http://dx.doi.org/10.1128/mcb.6.10.3373-3381.1986.
Abstract (sommario):
We examined the role that blockage of cells in the cell cycle may play in the stimulation of gene amplification and enhancement of drug resistance. We found that several different inhibitors of DNA synthesis, which were each able to block cells at the G1-S-phase boundary, induced an enhanced cycloheximide-sensitive synthesis of an early S-phase cell cycle-regulated enzyme, dihydrofolate reductase, and of other proteins as well. This response was specific, in that blockage at the G2 phase did not result in overproduction of the enzyme. When the cells were released from drug inhibition, DNA synthesis resumed, resulting in a cycloheximide-sensitive elevation in DNA content per cell. We speculate that the excess DNA synthesis (which could contribute to events detectable later as gene amplification) is a consequence of the accumulation of S-phase-specific proteins in the affected cells, which may then secondarily influence the pattern of DNA replication.
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Johnston, R. N., J. Feder, A. B. Hill, S. W. Sherwood e R. T. Schimke. "Transient inhibition of DNA synthesis results in increased dihydrofolate reductase synthesis and subsequent increased DNA content per cell." Molecular and Cellular Biology 6, n. 10 (ottobre 1986): 3373–81. http://dx.doi.org/10.1128/mcb.6.10.3373.
Abstract (sommario):
We examined the role that blockage of cells in the cell cycle may play in the stimulation of gene amplification and enhancement of drug resistance. We found that several different inhibitors of DNA synthesis, which were each able to block cells at the G1-S-phase boundary, induced an enhanced cycloheximide-sensitive synthesis of an early S-phase cell cycle-regulated enzyme, dihydrofolate reductase, and of other proteins as well. This response was specific, in that blockage at the G2 phase did not result in overproduction of the enzyme. When the cells were released from drug inhibition, DNA synthesis resumed, resulting in a cycloheximide-sensitive elevation in DNA content per cell. We speculate that the excess DNA synthesis (which could contribute to events detectable later as gene amplification) is a consequence of the accumulation of S-phase-specific proteins in the affected cells, which may then secondarily influence the pattern of DNA replication.
12
Lu, Zhongdeng, Zulin Chen e Wei Xie. "A Study on the Material Composition and Traceability of the Wellhead Blockage in the Process of Oil and Gas Exploitation—A Case of the DH231 Well in the Tarim Basin, China". Applied Sciences 13, n. 3 (23 gennaio 2023): 1504. http://dx.doi.org/10.3390/app13031504.
Abstract (sommario):
The formation of wellhead blockage increases operating costs and seriously affects the safe production of oil wells. It is crucial to correctly analyze the blockage composition and determine the reasons for wellhead blockage to improve the production efficiency of oil wells. In this study, the material composition and origin of the wellhead blockage in Well DH231 are systematically investigated by means of a thin-section observation, scanning electron microscope, energy spectrum analysis, and molecular geochemical characterization of organic matter. The results show that the wellhead blockage in Well DH231 consists of organic and inorganic materials. The inorganic material was mainly composed of dolomite, fine sand, and unknown black minerals. Four elements, Fe, O, Na, and Cl, could account for 95% of the total elemental content in the unknown minerals. It is speculated that they may have come from rust on the metal parts of the inner wall of the wellbore while being influenced by groundwater during the formation process. The organic matter in the blockage was an oil stain from the geological body. The coexistence of n-alkanes and 25-norhopanes in the oil stain was obvious. It indicated that the oldest crude oil in Well DH231 experienced severe biodegradation, followed by the secondary injection of hydrocarbons. The distribution characteristics of hopanes and steranes in oil stains in Well DH231 were comparable to those of the carboniferous crude oil in neighboring Wells DH4 and DH5. The oil stains in the wellhead blockage may be the product of oil and gas migration in Wells DH4 and DH5.
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Wu, Ai Xiang, Gao Hui Yao e Ming Qing Huang. "Influence Factors of Permeability during Heap Leaching of Complex Copper Oxide Ore". Advanced Materials Research 347-353 (ottobre 2011): 1037–43. http://dx.doi.org/10.4028/www.scientific.net/amr.347-353.1037.
Abstract (sommario):
In order to explore the influence factors of permeability during heap leaching of Yangla copper ore in China, falling head permeability test was applied to draw a comparison between the permeability of various samples, and then permeability evolutionary law of the sample ore from leaching heap was analyzed under different ore size or compaction degree. Finally, acid leaching experiments was carried out to reveal the influential mechanism of heap blockage on its permeability. The data show that the permeability coefficient of washed ore is 12.7 times than that of raw ore; permeability coefficient with the compaction degree 38.3% is only 3.78% of that in natural state; Chemical blockage brings about a fall of permeability coefficient by 93.5%, and earlier physical blockage leads to the decrease of it by 43.2%. Results show that much argillaceous fine particles in ore heap with high mud content can result in decreased permeability coefficient; and permeability coefficient of the samples decreases significantly with increased compaction degree. In addition, chemical blockage is the main reason for penetration deterioration.
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Zhang, Jiabao, e Dingqi Li. "Research on Optimization of Large Flow Hydraulic Punching Process in Zhaozhuang Mine". Geofluids 2022 (29 dicembre 2022): 1–14. http://dx.doi.org/10.1155/2022/7535215.
Abstract (sommario):
Taking hydraulic punching test of Zhaozhuang Mine as engineering background, by comparing the field application effects of different hydraulic punching processes, the relationship between coal moisture content around the borehole blockage and gas extraction effect was monitored and analyzed. The following conclusions were drawn: the occurrence of borehole blockage was the result of the comprehensive action of coal slag particle size and slag discharge capacity of punching return water. Blocking the borehole led to the accumulation of a large amount of punching high-pressure water and coal slag in the borehole, which compressed and infiltrated the surrounding coal body and reduced gas extraction efficiency of borehole. Under the condition of the same amount of coal produced by punching, the different punching methods led to the great difference in the influence radius of punching. The large flow three-stage coal-breaking hydraulic punching system developed according to the borehole blockage mechanism can effectively reduce the particle size of coal slag, increase the punching flow, effectively avoid borehole blockage, and improve gas extraction efficiency of borehole.
15
Li, Jinfeng, Huie Chen, Xiaoqing Yuan e Wenchong Shan. "Analysis of the Effectiveness of the Step Vacuum Preloading Method: A Case Study on High Clay Content Dredger Fill in Tianjin, China". Journal of Marine Science and Engineering 8, n. 1 (13 gennaio 2020): 38. http://dx.doi.org/10.3390/jmse8010038.
Abstract (sommario):
As a solution to avoid the blockage of the drainage pipe by traditional vacuum preloading, step vacuum preloading (SVP) has been progressively studied. However, the effectiveness of this technique has yet to be systematically analyzed. In this study, an indoor model test was conducted in which vacuum pressure was applied in five stages (10, 20, 40, 60, and 80 kPa) to dredger soil with high clay content at a reclamation site in Binhai New Area, Tianjin, China. The extent of the consolidation effect of the soil was determined, and the effectiveness of the step vacuum preloading method to address drainage pipe blockage was evaluated. The results indicate that soil settlement increases at each stage of vacuum pressure treatment and the degree of vertical consolidation at each stage exceeds 90%. At the end of the treatment stage with vacuum pressure of 80 kPa, the weakly bound water was discharged. Dissipation of pore water pressure occurred in all stages. On the basis of these results, it is shown that SVP can efficiently reinforce dredger fill. Moreover, after SVP, the grain size of the soil and void ratio are still uniformly distributed. Regardless of their location from the drainage pipe, soil exhibits permeability coefficients within the same order of magnitude. The consolidation effect of soil in each stage and the increased drainage rate in the initial stage of vacuum preloading with 80 kPa indicate that the test in the current study can decrease the horizontal displacement of fine particles and can avoid drainage pipe blockage.
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Machado, Florencio J. D. M., Juan Marta-Enguita, Susan U. Gómez, Jose A. Rodriguez, José Antonio Páramo-Fernández, María Herrera, Beatriz Zandio et al. "Transcriptomic Analysis of Extracellular Vesicles in the Search for Novel Plasma and Thrombus Biomarkers of Ischemic Stroke Etiologies". International Journal of Molecular Sciences 25, n. 8 (16 aprile 2024): 4379. http://dx.doi.org/10.3390/ijms25084379.
Abstract (sommario):
Accurate etiologic diagnosis provides an appropriate secondary prevention and better prognosis in ischemic stroke (IS) patients; still, 45% of IS are cryptogenic, urging us to enhance diagnostic precision. We have studied the transcriptomic content of plasma extracellular vesicles (EVs) (n = 21) to identify potential biomarkers of IS etiologies. The proteins encoded by the selected genes were measured in the sera of IS patients (n = 114) and in hypertensive patients with (n = 78) and without atrial fibrillation (AF) (n = 20). IGFBP-2, the most promising candidate, was studied using immunohistochemistry in the IS thrombi (n = 23) and atrium of AF patients (n = 13). In vitro, the IGFBP-2 blockade was analyzed using thromboelastometry and endothelial cell cultures. We identified 745 differentially expressed genes among EVs of cardioembolic, atherothrombotic, and ESUS groups. From these, IGFBP-2 (cutoff > 247.6 ng/mL) emerged as a potential circulating biomarker of embolic IS [OR = 8.70 (1.84–41.13) p = 0.003], which was increased in patients with AF vs. controls (p < 0.001) and was augmented in cardioembolic vs. atherothrombotic thrombi (p < 0.01). Ex vivo, the blockage of IGFBP-2 reduced clot firmness (p < 0.01) and lysis time (p < 0.001) and in vitro, diminished endothelial permeability (p < 0.05) and transmigration (p = 0.06). IGFBP-2 could be a biomarker of embolic IS and a new therapeutic target involved in clot formation and endothelial dysfunction.
17
Wang, Hui, Gang Ling, Mingyu Hu, Wene Wang e Xiaotao Hu. "Physical Clogging Characteristics of Labyrinth Emitters under Low-Quality (Sand-Laden Water) Irrigation". Agronomy 12, n. 7 (5 luglio 2022): 1615. http://dx.doi.org/10.3390/agronomy12071615.
Abstract (sommario):
Drip irrigation technology has obvious advantages in solving the shortage of agricultural water. The demand for using low-quality water sources for irrigation is becoming urgent. Research on the physical blockage formation has become the main part of solving the emitter blockage in China. The purpose of this study is to investigate the blockage characteristics of the emitters in the drip irrigation system with a low-quality water source and to provide some basis for the anti-clogging measures. Therefore, we configured different concentrations (1.8 g/L, 2.8 g/L, 3.8 g/L) and different particle sizes (0–0.054 mm, 0.054–0.075 mm, 0.075–0.1 mm) of low-quality water sources and carried out drip irrigation tests. The holistic and local characteristics of the physical blockage occurrence and distribution were compared under the sand-laden water source irrigation, then the structure and element composition of the blockage material were analyzed. The results show that the clogging characteristics are related to the emitter types, sediment content, and sediment particle size. The higher sediment concentration means that the single emitter is more likely to be blocked completely, and the whole clogging development is short and quick. However, at lower sediment concentration treatments, the probability of complete clogging decreases, and the clogging process is uniform and slow. The blockage position of large flow channel emitters (E1) appears at the head and middle of the drip irrigation tape, and the internal blockage usually occurs at the inlet. The small size channel emitters (E2 and E3) are concentrated in the head and end of drip irrigation tape, and the internal blockage usually occurs in the low-speed zone of the labyrinth channel such as the inlet fence. The internal blocked material is the accumulation structure formed by sediment particles and the coupled precipitation aggregate formed by the reaction of various chemical ions. Among them, the mixing of large and small sediment particles is more inclined to form a stable blocking skeleton structure.
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Sladek, C. D., K. Y. Fisher, H. E. Sidorowicz e J. R. Mathiasen. "Osmotic stimulation of vasopressin mRNA content in the supraoptic nucleus requires synaptic activation". American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 268, n. 4 (1 aprile 1995): R1034—R1039. http://dx.doi.org/10.1152/ajpregu.1995.268.4.r1034.
Abstract (sommario):
The role of synaptic input to the vasopressin neurons in hypertonicity-induced increase in vasopressin mRNA content was evaluated. Synaptic connection with the anterior hypothalamus is required for hypertonicity to increase vasopressin release. However, the potential for other mechanisms to induce the increase in vasopressin mRNA content is suggested by the fact that hypertonicity induces depolarization of supraoptic neurons independently of synaptic input. Explants of the hypothalamoneurohypophysial system were used to study the effect of depolarization and hypertonicity in the presence and absence of nonspecific synaptic blockade by 15 mM MgSO4 or blockade of excitatory amino acid receptors with kynurenic acid. Vasopressin release and mRNA content were increased by depolarization with 40 mM KCl and by exposure to hypertonicity (P < 0.05). Basal and osmotically stimulated vasopressin release was decreased by MgSO4 and by kynurenic acid. Both agents prevented the hypertonicity-induced increase in vasopressin mRNA content. Thus either synaptic input or increased VP release is required for hypertonicity to increase vasopressin mRNA, and excitatory amino acids are implicated in this response.
19
Inoue, Masaru, Michael McHugh e Hanna M. Pappius. "The Effect of α-Adrenergic Receptor Blockers Prazosin and Yohimbine on Cerebral Metabolism and Biogenic Amine Content of Traumatized Brain". Journal of Cerebral Blood Flow & Metabolism 11, n. 2 (marzo 1991): 242–52. http://dx.doi.org/10.1038/jcbfm.1991.56.
Abstract (sommario):
Widespread decrease in local cerebral glucose utilization (LCGU) previously shown to occur 3 days after a focal freezing lesion was interpreted as reflecting a depression of functional activity in the affected areas. In parallel experiments, cortical norepinephrine (NE) content of traumatized brain was found to be decreased. The effects of prazosin (PZ), an α1-adrenergic receptor blocker, and yohimbine (YOH), an α2-blocker, on glucose use and biogenic amine content of lesioned rat brain were studied to determine if the changes in the noradrenergic system associated with injury are of functional importance, to identify the receptors that may be involved in mediating the action of NE in injured brain, and to look for evidence of interaction between the noradrenergic and the serotonergic systems in traumatized brain. PZ (1 mg/kg) given 30 min before the lesion ameliorated the subsequent metabolic cortical depression seen in untreated animals. PZ given for 3 days starting before the lesion (3 mg/kg/day) was also effective in normalizing LCGU in areas where it was depressed by lesioning, despite the fact that this regimen induced significant global decrease in LCGU in normal animals. Once cortical metabolic depression had developed 3 days after the lesion, it could not be modified by PZ. YOH was less effective than PZ and was so only when given for 3 days (22.5 mg/kg/day in three divided doses). PZ (3 mg/kg/day in three divided doses) slightly but significantly decreased the accumulation of the serotonin (5-HT) metabolite 5-hydroxyindoleacetic acid in the traumatized hemisphere. These results provide evidence that blockage of α1adrenergic receptors prevents the development of cortical dysfunction associated with brain trauma. This implies that the noradrenergic system plays a role in the functional consequences of injury and that this effect is, at least in part, mediated by α1-adrenergic receptors. Furthermore, α1-adrenergic receptor blockage appears to modulate cortical turnover of 5-HT, previously also implicated in functional consequences of brain injury. The data are compatible with inhibitory effects of NE in the cortex and suggest a potential of α1-adrenergic blockage in development of novel therapeutic approaches to brain injury.
20
Sia, T. C., S. J. Brookes, P. G. Dinning, D. A. Wattchow e N. J. Spencer. "Peristalsis and propulsion of colonic content can occur after blockade of major neuroneuronal and neuromuscular transmitters in isolated guinea pig colon". American Journal of Physiology-Gastrointestinal and Liver Physiology 305, n. 12 (15 dicembre 2013): G933—G939. http://dx.doi.org/10.1152/ajpgi.00257.2013.
Abstract (sommario):
We recently identified hexamethonium-resistant peristalsis in the guinea pig colon. We showed that, following acute blockade of nicotinic receptors, peristalsis recovers, leading to normal propagation velocities of fecal pellets along the colon. This raises the fundamental question: what mechanisms underlie hexamethonium-resistant peristalsis? We investigated whether blockade of the major receptors that underlie excitatory neuromuscular transmission is required for hexamethonium-resistant peristalsis. Video imaging of colonic wall movements was used to make spatiotemporal maps and determine the velocity of peristalsis. Propagation of artificial fecal pellets in the guinea pig distal colon was studied in hexamethonium, atropine, ω-conotoxin (GVIA), ibodutant (MEN-15596), and TTX. Hexamethonium and ibodutant alone did not retard peristalsis. In contrast, ω-conotoxin abolished peristalsis in some preparations and reduced the velocity of propagation in all remaining specimens. Peristalsis could still occur in some animals in the presence of hexamethonium + atropine + ibodutant + ω-conotoxin. Peristalsis never occurred in the presence of TTX. The major finding of the current study is the unexpected observation that peristalsis can occur after blockade of the major excitatory neuroneuronal and neuromuscular transmitters. Also, the colon retained an intrinsic polarity in the presence of these antagonists and was only able to expel pellets in an aboral direction. The nature of the mechanism(s)/neurotransmitter(s) that generate(s) peristalsis and facilitate(s) natural fecal pellet propulsion, after blockade of major excitatory neurotransmitters, at the neuroneuronal and neuromuscular junction remains to be identified.
21
Correll, Christoph U. "Switching and Combining Antipsychotics". CNS Spectrums 15, S6 (aprile 2010): 8–11. http://dx.doi.org/10.1017/s1092852900027693.
Abstract (sommario):
Pharmacologic knowledge can inform clinical decision-making, particularly the dosing and switching decisions made with antipsychotics. Of relevance are the pharmacokinetic (what does the body do to the drug) and the pharmacodynamic (what does the drug do to the body) properties of antipsychotics.The goal of antipsychotic dosing is to achieve sufficient dopa-mine blockade in areas where dopamine excess can lead to psychosis, mania, or aggression. Using positron emission topography, one investigation showed that response rates were considerably higher in patients who achieved >65% striatal dopamine blockade. Conversely, striatal dopamine blockade >80% predicted the emergence of extrapyramidal symptoms (EPS) or akathisia.There is, however, considerable intra-individual variability in achieving the desired 60% to 80% striatal dopamine blockade. Such variability is likely due to inter-individual differences in the absorption, distribution, metabolism and elimination of medications. At the same time, antipsychotics themselves differ in their general pharmacokinetic profiles. For example, ziprasidone absorption is ~50% less when ingested on an empty stomach than when taken with a meal; the degree of absorption depends on the caloric content, while the fat content is not relevant.
22
Robinson, Matthew M., Christopher Bell, Frederick F. Peelor e Benjamin F. Miller. "β-Adrenergic receptor blockade blunts postexercise skeletal muscle mitochondrial protein synthesis rates in humans". American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 301, n. 2 (agosto 2011): R327—R334. http://dx.doi.org/10.1152/ajpregu.00160.2011.
Abstract (sommario):
β-Adrenergic receptor (AR) signaling is a regulator of skeletal muscle protein synthesis and mitochondrial biogenesis in mice. We hypothesized that β-AR blockade blunts postexercise skeletal muscle mitochondrial protein synthesis rates in adult humans. Six healthy men (mean ± SD: 26 ± 6 yr old, 39.9 ± 4.9 ml·kg−1·min−1 peak O2 uptake, 26.7 ± 2.0 kg/m2 body mass index) performed 1 h of stationary cycle ergometer exercise (60% peak O2 uptake) during 1) β-AR blockade (intravenous propranolol) and 2) administration of saline (control). Skeletal muscle mitochondrial, myofibrillar, and sarcoplasmic protein synthesis rates were assessed using [2H5]phenylalanine incorporation into skeletal muscle proteins after exercise. The mRNA content of signals for mitochondrial biogenesis was determined using real-time PCR. β-AR blockade decreased mitochondrial (from 0.217 ± 0.076 to 0.135 ± 0.031%/h, P < 0.05), but not myofibrillar or sarcoplasmic, protein synthesis rates. Peroxisome proliferator-activated receptor-γ coactivator-1α mRNA was increased ∼2.5-fold ( P < 0.05) at 5 h compared with 1 h postexercise but was not influenced by β-AR blockade. We conclude that decreased β-AR signaling during cycling can blunt the postexercise increase in mitochondrial protein synthesis rates without affecting mRNA content.
23
Subramanian, Srividya, e Regis R. Vollmer. "Depletion of brown fat norepinephrine content by acute cold exposure and adrenoceptor blockade". Pharmacology Biochemistry and Behavior 68, n. 3 (marzo 2001): 597–602. http://dx.doi.org/10.1016/s0091-3057(01)00457-9.
24
Polkowski, George R. "Degradation of Reservoir Quality by Clay Content, Unayzah Formation, Central Saudi Arabia". GeoArabia 2, n. 1 (1 gennaio 1997): 49–64. http://dx.doi.org/10.2113/geoarabia020149.
Abstract (sommario):
ABSTRACT Reservoirs in Central Saudi Arabia are important new sources of light sulfur-free crude oil. Development work on these wells has shown the adverse effect of authigenic clay minerals on their productivity or injectivity. The clay minerals may be affected during drilling of the well, during completion, during production, and/or injection. Kaolinite, chlorite, illite, and ordered and random mixed layer illite/smectite are commonly occurring authigenic clay minerals within the Permian Unayzah reservoir rock. As little as 2 weight percent clay causes permeability to be drastically reduced. Formation damage due to clay minerals results from: (1) swelling of smectite caused by injection water or drilling fluids of low salinity; (2) clay mineral migration and subsequent pore blockage; (3) precipitation of gelatinous pore-blocking iron hydroxides caused by the dissolution of chlorite by acid; (4) high water saturations; and (5) disaggregation of poorly consolidated parts of the reservoir into its component sand grains if the weak clay cements are disturbed. The implementation of clay control measures has resulted in increased production while minimizing formation damage.
25
Longhurst, J. C., T. I. Musch e G. A. Ordway. "O2 consumption during exercise in dogs--roles of splenic contraction and alpha-adrenergic vasoconstriction". American Journal of Physiology-Heart and Circulatory Physiology 251, n. 3 (1 settembre 1986): H502—H509. http://dx.doi.org/10.1152/ajpheart.1986.251.3.h502.
Abstract (sommario):
To examine the influence of alpha-adrenergic vasoconstriction on the aerobic capacity of dogs, we calculated O2 consumption (VO2) by the Fick method during submaximal and maximal exertion before and during alpha-adrenergic blockade with phentolamine. Regional blood flow was measured with radioactive microspheres. alpha-Adrenergic receptor blockade reduced VO2 by 12.9% during submaximal and 17.9% during maximal exercise. Arterial and venous lactic acid approximately doubled during both levels of stress in the presence of alpha-adrenergic receptor blockade. Calculated VO2 decreased because arteriovenous O2 (A-V)O2 extraction was reduced by 11.6% during submaximal exercise. During maximal exercise a 16.7% decrease in (A-V)O2 extraction and a 5.7% decrease in cardiac output contributed to the decrease in maximal VO2. During both levels of stress, (A-V)O2 extraction was reduced because arterial O2 content was decreased. Since circulating hematocrits during exercise were reduced by alpha-adrenergic receptor blockade (43-38%), we postulate that splenic contraction likely was inhibited. Additionally, distribution of blood flow to skeletal muscle and visceral organs was unaltered by alpha-blockade. To examine the importance of splenic contraction during maximal exercise, we examined hemodynamic and metabolic responses before and after splenectomy. Compared with the spleen-intact condition, splenectomized dogs demonstrated a 12.6% reduction in VO2 as a result of 7.7 and 5.5% reductions in (A-V)O2 extraction and cardiac output, respectively. (A-V)O2 extraction was reduced because arterial O2 content and circulating hematocrit during exercise were decreased. Therefore, in the exercising dog, alpha-adrenergic receptor blockade reduces O2 consumption and causes a shift to anaerobic metabolism.(ABSTRACT TRUNCATED AT 250 WORDS)
26
Verma, S., S. Bhanot e J. H. McNeill. "Effect of chronic endothelin blockade in hyperinsulinemic hypertensive rats". American Journal of Physiology-Heart and Circulatory Physiology 269, n. 6 (1 dicembre 1995): H2017—H2021. http://dx.doi.org/10.1152/ajpheart.1995.269.6.h2017.
Abstract (sommario):
Evidence suggests that hyperinsulinemia may be causally related to the development of high blood pressure (BP) in fructose-hypertensive (FH) rats. Because plasma insulin has been shown to modulate endothelin (ET) release in vivo, we hypothesized that hyperinsulinemia may provide a continual stimulus for ET release, which could increase BP by altering plasma or blood vessel ET levels. To test this hypothesis, we studied the effect of chronic ET-receptor blockade (by using bosentan, a noncompetitive ET antagonist) on plasma insulin levels, plasma ET levels, blood vessel ET content, and BP in FH rats. Chronic oral bosentan treatment (100 mg.kg-1.day-1) was initiated in 6-wk-old Sprague-Dawley rats. One week after bosentan treatment was started, rats were fed either normal rat chow or a fructose-enriched diet. Plasma insulin, plasma glucose, and systolic BP were measured weekly. At termination (in 15-wk-old rats), plasma ET levels and total mesenteric ET content were determined. Bosentan treatment caused a sustained decrease in BP in the FH rats (treated 130 +/- 4 vs. untreated 149 +/- 2 mmHg, P < 0.001) but had no effect in the normotensive control group. FH rats had a higher total mesenteric ET content compared with the control group (21.5 +/- 3.2 vs. 14.1 +/- 2.1 fmol, P < 0.05). Bosentan treatment did not alter total mesenteric ET content (treated 18.8 +/- 5 fmol, P > 0.05 vs. untreated) nor did it affect plasma insulin or ET levels in any group. These data suggest that ET may be involved in the development of high BP in FH rats. Whether ET represents an intermediate, linking hyperinsulinemia to hypertension in rats, or is an independent hypertensinogenic mechanism remains to be determined.
27
Pearson, Mike, Glen Van Der Kraak e E. Don Stevens. "In vivo pharmacology of spleen contraction in rainbow trout". Canadian Journal of Zoology 70, n. 3 (1 marzo 1992): 625–27. http://dx.doi.org/10.1139/z92-091.
Abstract (sommario):
Rainbow trout, Oncorhynchus mykiss, were injected with an adrenergic agonist, an adrenergic antagonist, or a cholinergic antagonist, via a dorsal aorta cannula. Spleen size and haemoglobin content were measured at rest and, for antagonists, following an air exposure stress. Injection of phentolamine (an α-antagonist) blocked the spleen contraction induced by air exposure, suggesting that control is mediated by α-adrenergic receptors. Air exposure effects were unaffected by β-adrenergic blockade or muscarinic cholinergic blockade.
28
Wang, Xueyong, Qingbo Wang, Kathrin L. Engisch e Mark M. Rich. "Activity-Dependent Regulation of the Binomial Parameters p and n at the Mouse Neuromuscular Junction In Vivo". Journal of Neurophysiology 104, n. 5 (novembre 2010): 2352–58. http://dx.doi.org/10.1152/jn.00460.2010.
Abstract (sommario):
Block of neurotransmission at the mammalian neuromuscular junction triggers an increase in the number of vesicles released (quantal content). The increase occurs whether nerve and muscle activity are both blocked by placement of a tetrodotoxin (TTX) containing cuff on the nerve or whether muscle activity is selectively blocked by injection of α-bungarotoxin (BTX). We used ANOVA to examine whether the mechanism underlying the increase in quantal content differed between the two types of activity blockade. We found that TTX-induced blockade increased the probability of release ( p), whereas BTX-induced blockade increased the number of releasable vesicles ( n). The lack of increase in p when postsynaptic activity was blocked with BTX suggests that block of presynaptic activity triggers the increase. To determine whether n is regulated by mismatch of pre- and postsynaptic activity introduced by BTX injection we combined BTX and TTX and still found an increase in n. We conclude that block of acetylcholine binding to acetylcholine receptors during spontaneous release triggers the increase in n.
29
Ho, Adrienne K., Anthony M. H. Ho e Glenio B. Mizubuti. "Blockage of the tracheal bronchus: effects on blood oxygen content, partial pressure of oxygen, and intrapulmonary shunt". Advances in Physiology Education 42, n. 2 (1 giugno 2018): 383–86. http://dx.doi.org/10.1152/advan.00017.2018.
30
Fathy, Mahmoud, Abeer El Shahawy, Th Abdel Moghny e Ayman Nafady. "Enhanced desalination process using a Cu–ZnO-polyvinyl chloride-nylon nanofiltration membrane as a calcite antiscalant in reverse osmosis". Materials Express 10, n. 5 (1 maggio 2020): 671–79. http://dx.doi.org/10.1166/mex.2020.1677.
Abstract (sommario):
Treatment and cleaning of reverse osmosis (RO) membranes saturated with CaCO3/brine is a main issue in RO desalination processes. Herein, a Cu–ZnO-polyvinyl chloride (PVC)-nylon nanofiltration membrane was synthesized and utilized to minimize and/or eliminate CaCO3/brine during RO, along with probing the effects of Cu–ZnO antiscalant on calcite precipitation in normal aqueous and supersaturated CaCO3/brine solutions. Moreover, decreases in Ca2+ content over time were evaluated by electrical conductivity and pH measurements. Results revealed that Cu–ZnO nanocomposite substantially increases induction time and stimulates the formation of aragonite rather than calcite. A 2 mg/L dose of Cu–ZnO nanocomposite suppressed CaCO3 in both unsaturated and supersaturated solutions. In natural water sources (containing ∼500 mg/L calcium and ≈300 mg/L bicarbonate content), complete removal of CaCO3 blockage was achieved by using 2.5 mg/L of Cu–ZnO antiscalant, while in supersaturated water solutions (1000 mg/L calcium and ≈500 mg/L bicarbonate content), only 2 mg/L of Cu–ZnO antiscalant was required to fully remove the blockage. Importantly, addition of 2 mg/L of Cu–ZnO antiscalant to RO brine showed no apparent deposition on the membrane surface after 6 h, with a minimal flux decrease to 86.5%. Thus, Cu–ZnO-PVC-nylon nanofiltration membranes with low concentrations (2 mg/L) of Cu–ZnO antiscalant can play a significant role in the treatment of supersaturated CaCO3/brine water discharge.
31
Zhao, Zhen, Guangxiong Qin, Yinfei Luo, Songhe Geng, Linchao Yang, Ronghua Wen, Jiahao Chao e Liang Zhang. "Experimental Study on Reservoir Physical Properties and Formation Blockage Risk in Geothermal Water Reinjection in Xining Basin: Taking Well DR2018 as an Example". Energies 14, n. 9 (6 maggio 2021): 2671. http://dx.doi.org/10.3390/en14092671.
Abstract (sommario):
The Xining Basin in Qinghai Province, China, is rich in mid–low temperature geothermal resources, but the reinjection of geothermal water has not yet started. In this paper, the physical properties of rocks sampled from the newly drilled geothermal well DR2018 were analyzed, and a series of core flooding experiments was conducted to assess the formation blockage risk during water reinjection. The experimental results show that the geothermal reservoir has a low porosity of 1.64–18.68% and a low permeability of 0.04–7.23 md. The rocks are weakly consolidated, and the movable clay and sand particles account for 0.18–23.42 wt %, which results in a significant rate and salinity sensitivity. Even at low water flow velocity of 0.31–1.64 cm/min, the core permeability will drop by 35–53% after 25-144PV injection. An obvious fluctuation and decline in core permeability can also be observed as the injected water salinity decreases. The blockage risk induced by the invasion of low-content scaling and suspended particles in injected water can be covered up by the migration of movable particles in cores. The particle migration and blockage in the near-wellbore formation will be the main reason to cause the decline in the well’s geothermal reinjection capacity.
32
Meng, Xingbang, Minhui Qi, Zhan Meng, Tong Li e Zhongxiao Niu. "Visual Experimental Study on Gradation Optimization of Two-Stage Gravel Packing Operation in Unconventional Reservoirs". Energies 12, n. 8 (22 aprile 2019): 1519. http://dx.doi.org/10.3390/en12081519.
Abstract (sommario):
During the development of unconventional reservoirs with high sand production rate and fine silt content such as heavy oil and hydrate reservoirs, silt sand blockage problem is a serious issue. A two-stage gravel-packing sand control technique is applied to solve the silt sand blockage now. However, traditional experiments on this technique could not obtain the dynamic distribution law of intrusive sand in the gravel pack. In this study, a new visualization experiment based on hydrodynamic similarity criterion for studying particle blockage in gravel packs was conducted. Real-time monitoring of sand particle migration in the gravel pack could be achieved. Also, the stable penetration depth and the distributing disciplinarian of invaded particles could be determined. The results show that when the gravel-to-sand median size ratio of gravel bed I is less than five, the sand bridge can be formed at the front end of the gravel pack. This could prevent sand from further intruding. As the grain size of gravel bed II is increased, the flow velocity is reduced. Thus, the sand invading into gravel bed II tends to settle at the interface. A large amount of sand intrusion can happen to gravel pack II when the pore filling front breaks through the gravel bed I.
33
Brunetto de Farias, Caroline, Denis Broock Rosemberg, Tiago Elias Heinen, Patricia Koehler-Santos, Ana Lucia Abujamra, Flávio Kapczinski, Algemir Lunardi Brunetto et al. "BDNF/TrkB Content and Interaction with Gastrin-Releasing Peptide Receptor Blockade in Colorectal Cancer". Oncology 79, n. 5-6 (2010): 430–39. http://dx.doi.org/10.1159/000326564.
34
Castillo, Jenny, Joanne Curley, Joyce Hotz, Megumi Uezono, Joseph Tigner, Mark Chasin, Robert Wilder, Robert Langer e Charles Berde. "Glucocorticoids Prolong Rat Sciatic Nerve Blockade In Vivo from Bupivacaine Microspheres". Anesthesiology 85, n. 5 (1 novembre 1996): 1157–66. http://dx.doi.org/10.1097/00000542-199611000-00025.
Abstract (sommario):
Background Previous work showed that incorporation of dexamethasone (0.05 weight/weight percentage) into bupivacaine microspheres prolonged blockade by eight to 13 times compared with that produced by bupivacaine microspheres alone. The determinants of dexamethasone's block-prolonging effect were examined and reported here. Methods Polylactic-co-glycolic acid polymer microspheres (65/35) with 75 weight/weight percentage bupivacaine were prepared. Microspheres were injected adjacent to the rat sciatic nerve, and sensory and motor blockade were assessed. A procedure was developed to test drugs for block-prolonging ability in vivo by placing test drugs in the injection fluid along with a suspension of bupivacaine microspheres. Results Dexamethasone alone in suspension did not produce blockade, nor did it prolong blockade induced by aqueous bupivacaine. Bupivacaine microspheres (150 mg drug/kg rat weight) produced blockade for 6 to 10 h. Dexamethasone in the suspending solution of microspheres prolonged block by up to five times. Glucocorticoids prolonged block in proportion to glucocorticoid/antiinflammatory potency. The corticosteroid antagonist cortexolone inhibited dexamethasone's blockade-prolonging action. Durations of blockade with or without dexamethasone were unaltered by hydroxyurea-induced neutrophil depletion. Microspheres were extracted from rats at time points ranging from 7 h to 7 days, and residual microsphere dry weight and bupivacaine content were similar in groups of rats injected with either bupivacaine microspheres or bupivacaine microspheres containing dexamethasone, respectively. Conclusions Glucocorticoids prolong blockade from bupivacaine microspheres. The mechanism appears unrelated to the kinetics of bupivacaine release in vivo.
35
Abdelazim, Abotaleb, Mahmoud Abu El Ela, Ahmed El-Banbi e Helmy Sayyouh. "Successful approach to mitigate the asphaltenes precipitation problems in ESP oil wells". Journal of Petroleum Exploration and Production Technology 12, n. 3 (23 ottobre 2021): 725–41. http://dx.doi.org/10.1007/s13202-021-01335-7.
Abstract (sommario):
AbstractThis study introduces a comprehensive and cost-effective approach to diagnose and treat the asphaltenes precipitation problems in different downhole conditions. The proposed approach has been successfully applied in two oil wells (Well-I, and Well-II) located in the Western Desert of Egypt. The two wells produce oil of moderate to high oil gravity with low asphaltenes content using Electrical Submersible Pumps (ESP). In such operating conditions, solid deposits caused blockage at the pump intake and within the pumping stages in the two wells. This blockage led to a sharp decrease in oil production rate and a significant increase in the operating cost. The existing failure analysis procedure was not able to accurately identify the reasons for the blockage; accordingly, the treatment operations were unsuccessful. On the contrary, applying the proposed approach accurately (1) identified the type of the solid deposits, (2) solved the problem using proper treatment option with minimum cost, and (3) improved the oil production rate. The laboratory tests of the fluid and solid deposits showed that (1) the asphaltenes were unstable in the crude oil and acted as a glue for other minerals, and (2) the blockage was successfully diagnosed to confirm that the two wells had asphaltenes precipitation problem. The laboratory tests were extended to select optimum asphaltene dispersant for wells treatments. The field application results showed a significant increase in the oil production rate from 700 to 1600 STB/D in Well-I and from 470 to 1500 STB/D in Well-II. Moreover, the operating cost decreased considerably from 2.01 to 0.43 $/STB in Well-I, and from 4.37 to 0.52 $/STB in Well-II after applying the proposed approach.
36
Li, Yu, Meilong Fu, Baofeng Hou, Zhiyuan Zhang e Ruiyi Sun. "Experimental Study on Blockage Mechanism and Blockage Locations for Polymer-Flooded Reservoirs in the Henan Oilfield". Geofluids 2021 (16 aprile 2021): 1–11. http://dx.doi.org/10.1155/2021/6669921.
Abstract (sommario):
To address the issues of reservoir blockage and sharp decline in fluid output of production wells in the polymer injection zone of the Henan oilfield, physical modeling has been used to study the blockage mechanism and blockage locations of the polymer-flooded reservoir based on oil reservoir characteristics and blockage knowledge. The results show that all the constant pressures in the low, moderate, and high permeability cores subjected to polymer injection and subsequent waterflooding were higher than the constant pressure during primary waterflooding; hence, polymer retention and blockage phenomena were obvious in the cores; in the high permeability core, the pore surface adsorbed more polymer molecules though pore throat radii were still much greater than the size of the polymer molecule, suggesting that polymer blockage is mainly caused by adsorption and retention. For the low permeability core, the specific surface area of the inlet end was much larger than that in the high permeability core, leading to more serious capture of polymer molecules at the small pores, indicating that blockage under polymer injection is mainly caused by capture and retention; for the lower permeability (91.81 mD) core, as compared with the case prior to polymer injection, the polymer-injected core had fewer large pores and throats, the mean pore throat radius decreased from 42.2 μm to 39.9 μm, and the mean throat-to-pore coordination number decreased from 3.36 to 3.19; thus, polymer capture and retention led to core blockage; the leftward shift of the curve corresponding to the porosity component, high porosity peak weakening after polymer injection, moderate and low porosity peaks appearing after polymer injection, and enhancement of lower porosity peaks indicate that, after polymer injection and subsequent waterflooding, polymer adsorption and capture led to blockage of some large pores; the highest pressure gradient, i.e., 6.3 MPa/m, was achieved at the P2-P3 segment; thus, the worst blockage occurred at the P2-P3 stage, or 1/8-1/4 of the sandpack length. In this paper, Nanbaxian oil and gas field, China, was taken as an example to investigate the interpretation method of gas saturation in a complex pore structure. The “four properties” relationship of the formation reservoir in the Nanbaxian oil and gas field was studied in depth according to the conventional logging data and core analysis data. The neural network algorithm was used to reconstruct the resistivity curve of the water layer to eliminate the influence of lithology, shale content, and pore structure on the resistivity. The difference between the reconstructed curve and the measured resistivity curve was used to identify the gas and water, and the ratio of the two was used to calculate the gas saturation, and good results were achieved. It was found that the sedimentary types of the Nanbaxian oil and gas field cause the reservoir to be thin, numerous, and dispersed; the lateral correlation is difficult. In addition, the structural features lead to the reservoir types being various in the vertical direction, which makes the identification of reservoir fluid more difficult. The results revealed that the rock compaction, poor physical properties, complex pore structure, high resistivity of surrounding rocks, and low formation water salinity make the water layer with high resistivity and difficult to identify gas and water.
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Chang, Peng, Rui Xue Shi, Li Wang, Wei Han, Cong Dan Ye e Yun Ma. "Study on Source Analysis of the Cation in Produced Water from Sulige Gas Field and Anti-Scaling Measures". Key Engineering Materials 814 (luglio 2019): 505–10. http://dx.doi.org/10.4028/www.scientific.net/kem.814.505.
Abstract (sommario):
A large amount of foreign matter appears in the Sulige gas well, causing blockage and corrosion of the pipeline, increasing the pressure difference in the wellbore and seriously affecting the normal production of the gas well. The gas wells with serious conditions mentioned above were selected to analyze the quality of single well produced water and the composition of blockage and core. Combined with the XRD analysis results of the cuttings, the long-term leaching experiments on the cuttings in different simulated solutions were carried out to study the sources of scaled ions in the gas wells. The experimental results showed that the extracted water from SD6-1 had high salinity and high content of scale ions Ca2+, Ba2+ and Sr2+;the main component of blockage is the acid insoluble strontium sulfate (barium) scale, and contains a small amount of corrosion products. The easily scalable Ca2+、Mg2+、Ba2+ and Sr2+ produced from the dissolution of the core in the formation water or working fluids, especially the acid erosion dissolves. According to the scaling mechanism, two kinds of Sr/Ba scale inhibitor were selected. The results showed that the barium II scale inhibitor performance is relatively good, and at the concentration of 40 mg/L, and the scale inhibition rate was more than 95%. The clogging of a single well can be reduced by adding a scale inhibitor.
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Manzoor, Ayesha, Muhammad Bashir, Muhammad Naveed, Muhammad Akhtar e Shaista Saeed. "Postharvest Chemical Treatment of Physiologically Induced Stem End Blockage Improves Vase Life and Water Relation of Cut Flowers". Horticulturae 10, n. 3 (11 marzo 2024): 271. http://dx.doi.org/10.3390/horticulturae10030271.
Abstract (sommario):
Wound-induced xylem occlusion significantly affects the vase life of cut flowers, as oxidative stress and the polymerization of phenolic compounds lead to the deposition of phenolic compounds/secondary metabolites in the stem ends of cut flowers to heal open tissues of freshly cut stems and prevent microbial invasion. However, this deposition causes blockage of vessels, reduced water uptake, and shortened vase life. The physiological plugging of vessels is linked with various oxidative enzymes’ (PAL, PPOs, LACs, and COs) actions taken to increase the synthesis of different compounds, e.g., lignin, suberin, tyloses, gel, and latex, in wounded areas. The use of chemical preservatives/enzyme inhibitors is one of the safest and most efficient techniques employed to minimize vascular blockage and inhibit phenolic compounds deposition and exudation. This review mainly discusses the types of oxidative enzymes, their pathways and biochemistry along with production of secondary metabolites, their biosynthesis, and their modes of action involved in vascular blockage. It also summarizes the different types of preservatives used in postharvest treatments to improve relative water uptake, flower fresh weight, petal protein content, and hydraulic conductance and prolong the vase life of cut flowers during storage. It is hoped that this elaborate study will help researchers in designing new studies concerning occlusion caused by the accumulation of phenolic compounds in vessels.
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Mateo Pérez, Vanesa, José Manuel Mesa Fernández, Francisco Ortega Fernández e Joaquín Villanueva Balsera. "Gross Solids Content Prediction in Urban WWTPs Using SVM". Water 13, n. 4 (8 febbraio 2021): 442. http://dx.doi.org/10.3390/w13040442.
Abstract (sommario):
The preliminary treatment of wastewater at wastewater treatment plants (WWTPs) is of great importance for the performance and durability of these plants. One fraction that is removed at this initial stage is commonly called gross solids and can cause various operational, downstream performance, or maintenance problems. To avoid this, data from more than two operation years of the Villapérez Wastewater Treatment Plant, located in the northeast of the city of Oviedo (Asturias, Spain), were collected and used to develop a model that predicts the gross solids content that reaches the plant. The support vector machine (SVM) method was used for modelling. The achieved model precision (Radj2 = 0.7 and MSE = 0.43) allows early detection of trend changes in the arrival of gross solids and will improve plant operations by avoiding blockages and overflows. The results obtained indicate that it is possible to predict trend changes in gross solids content as a function of the selected input variables. This will prevent the plant from suffering possible operational problems or discharges of untreated wastewater as actions could be taken, such as starting up more pretreatment lines or emptying the containers.
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Francini, Flavio, María C. Castro, Juan J. Gagliardino e María L. Massa. "Regulation of liver glucokinase activity in rats with fructose-induced insulin resistance and impaired glucose and lipid metabolism". Canadian Journal of Physiology and Pharmacology 87, n. 9 (settembre 2009): 702–10. http://dx.doi.org/10.1139/y09-064.
Abstract (sommario):
We evaluated the relative role of different regulatory mechanisms, particularly 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase (PFK2/FBPase-2), in liver glucokinase (GK) activity in intact animals with fructose-induced insulin resistance and impaired glucose and lipid metabolism. We measured blood glucose, triglyceride and insulin concentration, glucose tolerance, liver triglyceride content, GK activity, and GK and PFK2 protein and gene expression in fructose-rich diet (FRD) and control rats. After 3 weeks, FRD rats had significantly higher blood glucose, insulin and triglyceride levels, and liver triglyceride content, insulin resistance, and impaired glucose tolerance. FRD rats also had significantly higher GK activity in the cytosolic fraction (18.3 ± 0.35 vs. 11.27 ± 0.34 mU/mg protein). Differences in GK protein concentration (116% and 100%) were not significant, suggesting a potentially impaired GK translocation in FRD rats. Although GK transcription level was similar, PFK2 gene expression and protein concentration were 4- and 5-fold higher in the cytosolic fraction of FRD animals. PFK2 immunological blockage significantly decreased GK activity in control and FRD rats; in the latter, this blockage decreased GK activity to control levels. Results suggest that increased liver GK activity might participate in the adaptative response to fructose overload to maintain glucose/triglyceride homeostasis in intact animals. Under these conditions, PFK2 increase would be the main enhancer of GK activity.
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van Baak, M. A., A. de Haan, W. H. Saris, E. van Kordelaar, H. Kuipers e G. J. van der Vusse. "Beta-adrenoceptor blockade and skeletal muscle energy metabolism during endurance exercise". Journal of Applied Physiology 78, n. 1 (1 gennaio 1995): 307–13. http://dx.doi.org/10.1152/jappl.1995.78.1.307.
Abstract (sommario):
Twelve healthy male volunteers cycled to exhaustion at a workload corresponding to 70% of maximal aerobic power after administration of 80 mg of the beta 1+2-adrenoceptor antagonist propranolol and after administration of placebo by mouth. Exercise times until exhaustion were 39 +/- 7 and 86 +/- 7 min in the propranolol and placebo groups, respectively. Muscle inosine 5′-monophosphate content was significantly increased above resting levels at exhaustion after placebo. At exhaustion after propranolol, inosine 5′-monophosphate was not increased significantly and was lower than at exhaustion after placebo. No changes in ATP and the total adenine nucleotide content during exercise were found in the two tests. Muscle glycogen content was significantly reduced at exhaustion after placebo as well as after propranolol, but the levels were still significantly higher at exhaustion after propranolol than after placebo. No evidence for a shift in glycogen utilization among types I, IIa, and IIb fibers after propranolol was found. The results show that neither an imbalance between ATP utilization and ATP regeneration nor premature glycogen depletion, either in the whole muscle or in specific muscle fiber types, provides a satisfactory explanation for the premature fatigue during endurance exercise after propranolol.
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Gharaibeh, Raad Z., Wildson Vieira da Silva, Rachel Newsome, Shirlene Paul, Stephanie Hogue, Kristina Bowles, Lary Robinson et al. "6 – Intestinal Microbial Functional Content Better Defines Therapeutic Responses to Immune Checkpoint PD-1 Blockade". Gastroenterology 156, n. 6 (maggio 2019): S—2. http://dx.doi.org/10.1016/s0016-5085(19)36778-2.
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Beggar, Awatif. "Quelques facteurs à prendre en considération pour réussir son cours en ligne". Médiations et médiatisations, n. 2 (15 novembre 2019): 107–16. http://dx.doi.org/10.52358/mm.vi2.88.
Abstract (sommario):
Les innovations numériques sont de plus en plus nombreuses dans le domaine de l’enseignement. Ces nouvelles pratiques nécessitent la prise en considération de certains paramètres pour un meilleur apprentissage. En effet, l’effet de la fascination technologique ou "la pseudo-autonomie" des apprenants peuvent inhiber l’apprentissage et constituer des points de blocage dans le processus de l’enseignement en ligne. Quant à la littératie numérique, la scénarisation des contenus, la proposition d’activités et de projets pour motiver les étudiants, ils peuvent fonder une nouvelle relation au savoir à l’ère du numérique. La pédagogie en présentiel diffère de celle qu’il faut adopter en ligne. Passer de l’espace métrique à l’espace virtuel impose des changements d’ordre pédagogique à ne pas négliger pour réussir un cours en ligne.
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Wang, Longhai, Xiaoyu Chai, Juan Huang, Jinpeng Hu e Zhihong Cui. "Efficient and Low-Loss Cleaning Method for Non-Uniform Distribution of Threshed Materials Based on Multi-Wing Curved Combination Air Screen in Computational Fluid Dynamics/Discrete Element Method Simulations". Agriculture 14, n. 6 (5 giugno 2024): 895. http://dx.doi.org/10.3390/agriculture14060895.
Abstract (sommario):
During the operation of the longitudinal axis flow threshing device of a combine harvester, the threshed materials form accumulations and blockages on both sides of the screen surface, severely affecting the harvesting process. To evenly distribute the materials on the screen and solve the blockage issue, a multi-wing curved combination centrifugal fan is designed to match the mass distribution of the threshed materials. The movement mechanism of rice threshed materials in the cleaning shoe of a longitudinal axis flow combine harvester is investigated using the coupled CFD-DEM simulation method. The cleaning efficiency and performance of the traditional straight-blade fan screen device and the newly designed cleaning device are compared and analyzed, and field tests are conducted. The results show that the trajectory of the threshed materials cleaned by the device equipped with the multi-wing curved combination centrifugal fan is consistent with the mass distribution of the materials separated by the longitudinal axis flow threshing device. The absolute value of the centroid velocity of the material group in the X/Y direction is greater than that of the traditional fan, indicating that the movement speed of the particle group in the optimized fan is greater than that of the traditional fan. Therefore, in the actual cleaning process, the optimized fan’s air flow distribution more effectively accelerates the movement speed of the threshed materials, increasing the amount of materials cleaned per unit time, thereby improving the cleaning efficiency. Field comparative tests show that the designed cleaning device reduced the cleaning loss rate by up to 25.00% and the impurity content rate by 32.20%, achieving efficient and low-damage cleaning of the combine harvester. The study demonstrates the effectiveness of the proposed method for evenly distributing the materials and provides important reference for the study of other piled particle distribution systems.
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Zhang, Kanglei, Jiahui Li, Wenxuan Dong, Qing Huang, Xueru Wang, Kai Deng, Waseem Ali et al. "Luteolin Alleviates Cadmium-Induced Kidney Injury by Inhibiting Oxidative DNA Damage and Repairing Autophagic Flux Blockade in Chickens". Antioxidants 13, n. 5 (26 aprile 2024): 525. http://dx.doi.org/10.3390/antiox13050525.
Abstract (sommario):
Chickens are a major source of meat and eggs in human food and have significant economic value. Cadmium (Cd) is a common environmental pollutant that can contaminate feed and drinking water, leading to kidney injury in livestock and poultry, primarily by inducing the generation of free radicals. It is necessary to develop potential medicines to prevent and treat Cd-induced nephrotoxicity in poultry. Luteolin (Lut) is a natural flavonoid compound mainly extracted from peanut shells and has a variety of biological functions to defend against oxidative damage. In this study, we aimed to demonstrate whether Lut can alleviate kidney injury under Cd exposure and elucidate the underlying molecular mechanisms. Renal histopathology and cell morphology were observed. The indicators of renal function, oxidative stress, DNA damage and repair, NAD+ content, SIRT1 activity, and autophagy were analyzed. In vitro data showed that Cd exposure increased ROS levels and induced oxidative DNA damage and repair, as indicated by increased 8-OHdG content, increased γ-H2AX protein expression, and the over-activation of the DNA repair enzyme PARP-1. Cd exposure decreased NAD+ content and SIRT1 activity and increased LC3 II, ATG5, and particularly p62 protein expression. In addition, Cd-induced oxidative DNA damage resulted in PARP-1 over-activation, reduced SIRT1 activity, and autophagic flux blockade, as evidenced by reactive oxygen species scavenger NAC application. The inhibition of PARP-1 activation with the pharmacological inhibitor PJ34 restored NAD+ content and SIRT1 activity. The activation of SIRT1 with the pharmacological activator RSV reversed Cd-induced autophagic flux blockade and cell injury. In vivo data demonstrated that Cd treatment caused the microstructural disruption of renal tissues, reduced creatinine, and urea nitrogen clearance, raised MDA content, and decreased the activities or contents of antioxidants (GSH, T-SOD, CAT, and T-AOC). Cd treatment caused oxidative DNA damage and PARP-1 activation, decreased NAD+ content, decreased SIRT1 activity, and impaired autophagic flux. Notably, the dietary Lut supplement observably alleviated these alterations in chicken kidney tissues induced by Cd. In conclusion, the dietary Lut supplement alleviated Cd-induced chicken kidney injury through its potent antioxidant properties by relieving the oxidative DNA damage-activated PARP-1-mediated reduction in SIRT1 activity and repairing autophagic flux blockade.
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Mohd Nazri, Nur Khairul Bariyyah, e Nur Asyraf Md Akhir. "INVESTIGATION OF CLAY STABILIZER POTENTIAL FOR HIGH CLAY CONTENT FORMATION". Platform : A Journal of Engineering 6, n. 3 (30 settembre 2022): 24. http://dx.doi.org/10.61762/pajevol6iss3art20024.
Abstract (sommario):
Clay swelling has been studied for decades due to its damaging problem in the reservoir. It has caused permeability impairment due to blockage at the pore throat and reduction of the available pore spaces in the reservoir. The past few decades have seen rapid development of clay stabilizers to treat clay minerals near-wellbore region areas. However, there a limited study investigating the potential of clay stabilizers to prevent clay swelling throughout the reservoir. The present study aimed to investigate the potential of potassium chloride (KCl) and Poly-diallyldimethylammonium chloride (PolyDADMAC) as cationic clay stabilizers to mitigate the clay swelling phenomenon throughout the reservoir. This study conducted a series of free swelling tests on bentonite with varying brine salinity and clay stabilizer concentration. In addition, the rheological properties of KCl and PolyDADMAC were measured at 24°C and 98°C and at a 7.34 s–1 shear rate to determine its flow potential throughout the reservoir. The results showed that 0.3 wt.% to 1.5 wt.% of KCl and PolyDADMAC were able to control the expansion of bentonite immersed in an aqueous solution, with PolyDADMAC has shown excellent performance, whereas the bentonite expansion in PolyDADMAC solution is significantly lower than KCl. This result is driven by the fact that PolyDADMAC has greater amounts of cationic charges to neutralize abundant negative charges on clay mineral surfaces. Furthermore, the viscosity of 0.3 wt.% to 1.5 wt.% of KCl and PolyDADMAC at 24°C and 98°C recorded is low, which is 0.25 cP to 1.45 cP and 0.83 cP to 2.32 cP respectively. This low value proves its potential to be penetrated throughout the reservoir, not limited to near the wellbore region only.
Keywords: Cationic clay stabilizer, salinity, bentonite swelling, viscosity
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Liu, Xiuru, Yiqing Sun, Fangming Xue, Jingcheng Su, jiangjiang Qu e Feng Chen. "Research Progress on Control and Removal Technology of SO3 of Coal-fired Power Plants". E3S Web of Conferences 118 (2019): 01036. http://dx.doi.org/10.1051/e3sconf/201911801036.
Abstract (sommario):
SO3 is one of pollutants in flue gas of coal power plants. It mainly derived from coal combustion in boiler and selective catalytic reduction denitrification system. The content of SO3 in flue gas were influenced by the combustion mode, sulfur content in fuel, composition of denitrification catalyst and fly ash. SO3 and water vapour generated H2SO4 droplets. Sulfate secondary particles in atmosphere could cause haze, acid rain and other disastrous weather. High concentration of SO3 could cause blockage and corrosion and affect the safe operation of the units. The generation mechanism of SO3 was discussed. The latest research progress on control and removal technology of SO3 was summarized. The study in this paper provides a reference for pollutant treatment in coal-fired power plants.
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Dalton, Mazie F., e Steve Schoenekase. "Safety Issues: Anticoagulation and Neuraxial Blockade". Hospital Pharmacy 40, n. 6 (giugno 2005): 505–14. http://dx.doi.org/10.1177/001857870504000607.
Abstract (sommario):
Neuraxial blockade includes techniques of spinal or epidural anesthesia and continuous epidural analgesia. A rare but potentially catastrophic complication of neuraxial blockade is spinal hematoma and subsequent paraplegia. The risk of this complication is increased with patient specific risk factors, and with the concomitant use of antithrombotic drugs.1 The American Society of Regional Anesthesia and Pain Medicine have provided guidelines on the management of patients receiving neuraxial anesthesia and anticoagulation. While the anesthesia staff may be familiar with these guidelines, other practitioners may not be aware of them. In a retrospective review, we found that only eight of 69 (12%) patients with an indwelling epidural catheter over a 12-month period received no concomitant medications that may affect the coagulation system. Two patients received medications, which the guidelines recommend against. Patients receiving neuraxial anesthesia are at high risk to be prescribed medications that may affect coagulation. The pharmacy needs to assume vigilance and responsibility to notify anesthesiology or develop some fail-safe method for these orders to be screened and evaluated. Pharmacy software vendors could assist in this challenge by developing the software to effectively contend with this therapeutic issue.
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Tang, Bin, Ting Wang e Zi Ning Shan. "The Engineering Accident Analysis of Cast-In Situ Bored Pile". Advanced Materials Research 446-449 (gennaio 2012): 1514–19. http://dx.doi.org/10.4028/www.scientific.net/amr.446-449.1514.
Abstract (sommario):
Abstract: Cast-in situ bored pile is a common form of pile foundation and widely used in road and bridge engineering in China. Because of complex cast-in situ bored pile construction process, high technical content requirement, vulnerable to the impact of human and environmental factors, cast-in situ bored piles prone to various kinds of quality problems in the construction process, such as drilling deflection, drilling hole collapse and diameter reduction, wrong identification of pile-end’s bearing stratum, catheter tube blockage, reinforcement cage floating, pile breaking, pile silted, etc. These problems often make it difficult to meet the design requirements into a pile formation, and difficultly to remedy. In this paper, Zhoutian Zhenjiang bridge at Shaoguan City, Qujiang to Nanxiong highway A03 contract bid package cast-in situ bored pile foundation engineering encountered in the construction collapsed hole, inclined hole, catheter tube blockage and other issues for example to analyzes the cause of cast-in situ bored pile engineering accident, made appropriate preventive measures and processing method.
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Arina, Herlin, e Mohammad Nasikin. "Enhancement of Flow Properties Biodiesel Using Sorbitan Monooleate". Scientific Contributions Oil and Gas 45, n. 3 (1 dicembre 2022): 143–52. http://dx.doi.org/10.29017/scog.45.3.1262.
Abstract (sommario):
Depletion of fossil fuel and increased pollution caused by the burning of fossil fuel is a leading factor in to use of alternate energy especially palm oil biodiesel as a mixture of diesel oil fuel (B-XX). It was reported that the use of the B-20 caused a blockage in the vehicle’s fuel filter. The blockage is caused by the presence of deposits formed from the agglomeration of monoglycerides. Three different biodiesels with monoglyceride content were used 0.40% - 0.60% by mass. The addition of monoglyceride standards (monopalmitin, monostearin, and monoolein) to biodiesel increases the volume of monoglyceride precipitates formed. The presence of these deposits decreases the flow properties of B-20. Research has been carried out to improve the flow properties of biodiesel by adding Sorbitan Monooleate (CMOST) surfactant, especially cloud points (CP) and cold filter plugging point (CFPP) parameters. The addition of 0.10%w - 1%w CMOST can reduce the CP by 4.80oC and CFPP by 2oC. This proves that the addition of SMO will improve the flow properties of B-XX as an alternative energy.