Characteristics of CRM Binders and Mixtures Used in Nevada

The use of crumb rubber modified binders to improve the performance characteristics of hot mixed asphalt (HMA) mixtures have shown mixed results throughout the U.S. Some studies showed improved performance properties such as added resistance to rutting, fatigue, and low temperature cracking while some field performances have shown problems with raveling bleeding and aging of the CRM HMA mixtures. Before the Nevada Department of Transportation (NDOT) can assess the merit of using CRM HMA mixtures, it must have the following: 1-A system to evaluate the CRM binders in order to assign the binder most suitable for the environmental and traffi.c loading conditions of a particular pavement segment; 2-A procedure for mix design to select the most appropriate proportioning of binder and aggregate; 3-A mixture analysis system to predict the long-term performance of CRM mixtures under the combined action of environment and traffic loadings. It is necessary to develop a system that enables NDOT to predict the performance of CRM pavements before construction (as is done for traditional HMA mixes) and to select better pavement alternatives. In 1994, NDOT initiated a multi-year research project to develop a system for the evaluation of CRM binders and mixtures under Nevada's environmental and traffic conditions. The project started on January 1, 1994 and was completed on August 31, 1997

Evaluation of Rutting Resistance of Superpave and Hveem Mixtures: Volume III - Impact of Gyratory Compaction

This report represents the third in a series of four reports documenting the overall evaluation of rutting resistance of Superpave and Hveem mixtures. Specifically this report documents the evaluation of the impact of the gyratory compaction on the permanent deformation performance of HMA mixtures using the RSCH test

Laboratory Evaluation of Thin Asphalt Concrete Overlays for Pavement Preservation

A significant percentage of the existing lane miles of roadways in the United States, and in particular in Nevada, consists of rural roads. Thus, using a cost-effective pavement surface treatment becomes critical and essential in reducing maintenance and preservation costs on rural and low volume roads. The overall objective of this study was to assess the use of locally available materials in Nevada for the development of a durable fine-graded thin hot-mix asphalt (HMA) overlay mixture for pavement preservation. Accordingly, a comprehensive laboratory evaluation was conducted. The investigation considered establishing two mix designs using typical local materials for the northern and southern part of the state. For each mixture, the determined optimal binder content based on volumetric properties was varied within the allowable tolerances to simulate the potential variation in asphalt binder content during plant production. The performance of the two thin HMA mixtures were then evaluated at the various asphalt binder contents in terms of their resistance to moisture damage, resistance to surface raveling and abrasion, dynamic modulus property, resistance to rutting, and resistance to reflective cracking. Furthermore, the workability of the designed thin HMA overlay mixtures using the locking point concept in addition to the developed interlayer bond strength using the Louisiana Interlayer Shear Strength Tester were evaluated. Overall, both designed fine-graded mixtures showed a very good performance and are expected to perform well when used as a thin HMA overlay in Nevada. In particular, good stability, very good resistance to surface raveling and abrasion, and excellent resistance to reflective cracking were observed for both thin HMA overlay mixtures at all evaluated asphalt binder contents. A cost analysis was also conducted between the thin HMA overlay and a typically used pavement surface treatment. Based on the findings from this study, it was recommended to construct field test sections in various parts of the state to evaluate the field performance of the developed thin HMA overlay mixtures in Nevada

Préparation à petite et grande échelle des liposomes encapsulant l’huile essentielle de clou de girofle libre et sous forme de complexe d’inclusion dans l’hydroxypropyl-β-cyclodextrine : caractérisation des nanostructures et évaluation de leur effet antioxydant

Clove essential oil (CEO) and its major constituent eugenol (Eug) are recognized for their biological properties. These molecules may constitute natural alternatives to synthetic antimicrobial, antioxidant, and anti-inflammatory agents in food and pharmaceutical formulations. However, CEO constituents are volatile, sensitive to light and possess low aqueous solubility, which may limit their wide applications. Our thesis focuses on the preparation and characterization of lipid vesicles encapsulating CEO, Eug and the inclusion complexes cyclodextrin/Eug. In a first step, the ethanol injection method is applied at laboratory scale where the preparation parameters have been optimized. Natural hydrogenated (Phospholipon 80H, Phospholipon 90H) and non-hydrogenated (Lipoid S100) soybean phospholipids were used to study the effect of hydrogenation and phospholipid composition on the characteristics of liposomes. Optimal conditions were then applied to prepare liposomes at large scale by membrane contactor and at pilot scale. Similar results in terms of size, polydispersity index, zeta potential, morphology and phospholipid loading rate were obtained at laboratory and large scale. This indicates the reproducibility of the preparation methods. In addition, HP-β-CD/Eug and HP- β-CD/CEO inclusion complexes were prepared in aqueous solution and were then incorporated into liposomes forming a combined system « drug in cyclodextrin in liposomes, DCL ». Double loaded liposomes (DCL2) were also prepared where CEO or Eug were added in the organic phase and their inclusion complexes in the aqueous phase. Compared to CEO and Eug loaded liposomes, DCL and DCL2 improved the loading rate of Eug and possessed smaller vesicles size. Results showed that both liposomes and DCLs are stable and maintain the antioxidant activity of Eug. In addition, liposomes protect Eug from degradation induced by UVC irradiation. DCLs, whose characteristic is to keep a volatile essential oil in a lyophilized form despite the very low applied pressures, could be considered as a promising carrier system of CEO and Eug permitting their use as ingredients in cosmetic, pharmaceutical and food industriesL'huile essentielle de clou de girofle (HECG) et son constituant majeur l'eugénol (Eug) sont reconnus pour leurs propriétés biologiques. Ces principes actifs naturels peuvent constituer des alternatifs aux agents antimicrobiens, antioxydants et anti-inflammatoires de synthèse dans les formulations alimentaires et pharmaceutiques. Cependant, leur utilisation est limitée en raison de leur faible solubilité aqueuse, volatilité et sensibilité à la lumière. Notre travail de thèse porte sur la préparation et la caractérisation des vésicules lipidiques encapsulant l'HECG et l'Eug ainsi que les complexes d'inclusion cyclodextrine/Eug. Dans une première étape, la méthode d'injection éthanolique est utilisée à l'échelle du laboratoire où les paramètres de préparation ont été optimisés. Des phospholipides naturels de soja saturés (Phospholipon 80H et Phospholipon 90H) et insaturés (Lipoid S100) ont été utilisés pour étudier l'effet de l'hydrogénation et de la composition des phospholipides sur les caractéristiques des liposomes. Les conditions optimales ont été par la suite appliquées pour préparer les liposomes à grande échelle par contacteur à membrane et à l'échelle pilote. Des résultats similaires en termes de taille, indice de polydispersité, potentiel zêta, morphologie et taux d'incorporation de phospholipides sont obtenus à petite et grande échelle. Ceci indique la reproductibilité de ces procédés de préparation. Par ailleurs, des complexes d'inclusion d'HP-β-CD/Eug et d'HP-β-CD/HECG sont préparés dans une solution aqueuse et ensuite incorporés dans les liposomes formant un système combiné « drug in cyclodextrin in liposomes, DCL ». Un système en double encapsulation (DCL2) a été également préparé où l'Eug ou l'HECG sont ajoutés dans la phase organique et leurs complexes d'inclusion dans la phase aqueuse. En comparant à une simple incorporation dans les liposomes, DCL et DCL2 améliorent le rendement d'encapsulation de l'Eug et possèdent des tailles plus petites. Les résultats ont montré que les liposomes et les DCLs sont stables et maintiennent l'activité anti-oxydante de l'Eug. De plus, les liposomes protègent l'Eug contre la dégradation induite par les rayons UVC. Les DCLs, dont la particularité est de maintenir une huile essentielle volatile dans un lyophilisat en dépit des pressions très basses appliquées, peuvent être considérés comme un système de vectorisation prometteur de l'HECG et de l'Eug permettant leur utilisation en tant qu'ingrédients dans les préparations cosmétiques, pharmaceutiques, et agroalimentaire

Use Of Reclaimed Asphalt Pavements (RAP) In Airfields HMA Pavements

This report documents the results and findings of the AAPTP Project No. 05-06: Use of Reclaimed Asphalt Pavements (RAP) in Airfields HMA Pavements. The report includes a review of current technology in RAP pavements and its application in highway and airfield pavements. Additionally, the report includes the current highway specifications on the use of RAP and a mechanistically based method to transfer the RAP technology that has been successfully used on highway pavements into the design and specification systems for RAP on airport pavements. Review of in-service airfield pavements was conducted as part of this study. Furthermore, the report includes an evaluation of the impact of RAP on the performance life of HMA airfield pavements under three actual airport traffic mixes of a large hub, small hub, and general aviation. The Life cycle cost analysis used the characteristics and mechanical properties of HMA mixtures in the LEDFAA1.3 airfield pavement design software to compare the estimated performance life of HMA pavements with and without RAP materials. Finally, sections 401-3.3 and 403-3.3 of FAA’s P-401 and P-403 specifications, respectively, on RAP were reviewed and recommendations were made based on the findings of the research effort conducted in this project

Evaluation of Low Temperature Properties of HMA Mixtures

The deterioration of flexible pavements due to low temperature cracking is a significant and costly problem in the State of Nevada. The Nevada Department of Transportation initiated several research efforts aimed at exploring Nevada's problem with this distress. The research evaluated several newly developed low temperature performance tests under Nevada's conditions. The goal of the research was to determine the applicability of the tests for characterizing the low temperature response of Nevada's asphalt binders and HMA mixtures. This paper summarizes Nevada's experience with the SHRP low temperature tests and specifications; highlighting the effectiveness of the Superpave PG binder grading system and Thermal Stress Restrained Specimen Test. The contribution of asphalt aging to Nevada's cracking problem is also included in the paper. An investigation of the Superpave Performance Graded Binder tests has determined that the bending beam rheometer and the direct tension test correlate very well and it may not be necessary to run both tests as they are set up in the current Superpave specifications. The TSRST appears to provide the greatest value for evaluating low temperature properties of HMA mixtures. Findings from the research indicate that there are some significant correlations between the low temperature properties of asphalt binders and HMA mixtures if the mixtures are aged appropriately. This emphasizes the need to implement the appropriate conditioning procedure when low temperature cracking is used as part of the mix design and evaluation process. On the other hand, the research showed that when using polymer-modified asphalt binders, the low temperature grade of the asphalt binder maybe conservative enough where testing ofthe HMA mix may not be necessary

Variability Of The Moisture Sensitivity Of Field HMA Mixes

The objective of this study is to evaluate the variability in moisture sensitivity of lime treated HMA mixes that were sampled during construction from three projects located in the Truckee Meadows region

Nasogastric Tube Feeding-Induced Esophageal Bezoar: Case Description

Background. Bezoars are well established entities causing gastrointestinal obstructions. Depending on the prominent constituent of these bezoars, the latter are divided into four subtypes: pharmacobezoars, lactobezoars, trichobezoars, and phytobezoars. Less frequently reported types of bezoars are reported including those formed secondary to nasogastric tube feeding with casein-based formulas. Case Presentation. A 69-year-old male presented following cardiac arrest postmyocardial infarction. Patient sustained anoxic brain injury after resuscitation, rendering him ventilator dependant along with nasogastric tube feeding, initially. Dislodging of the nasogastric tube at one time rendered it difficult to reinsert it, with investigation showing the presence of calcified material within the distal oesophagus, mainly composed of casein-based products secondary to enteral feeding. Conclusion. Bezoars are well known to cause gastrointestinal obstructions due to their indigestible characteristics within the alimentary tract. More rare causes of bezoars include those formed from casein-based feeding formulas administered to patients with sustained enteral feeding. Esophageal obstruction, secondary to casein-based bezoars, occurs due to multiple risk factors, especially in those necessitating intensive care. Approach in such scenarios requires a multiteam approach

Adaptation of Syrah wine grape cultivar to changing climatic conditions of the Bekaa valley, Lebanon

Received: February 7th, 2023 ; Accepted: October 25th, 2023 ; Published: November 6th, 2023 ; Correspondence: [email protected] factors play a key role in determining the suitability of a given region for specific cultivars and wine types and the responses of individual grapevine cultivars to climate are of utmost importance for activity planning and decision making in viticulture. The study investigated the effect of climate conditions from 2006 till 2018 on the performance of cv. Syrah cultivated in two vineyards in Lebanon; Kanafar (at 1,020 m.a.s.l) and Mansoura (at 850 m.a.s.l). Cluster analysis based on climate indicators divided years into two clusters; in Kanafar (cluster 1: 2006–2015, cluster 2: 2016–2018) and in Mansoura (cluster 1: 2006 to 2008, cluster 2: 2009 to 2018). Solar radiation (May-June) and average wind speed (July-August-September) were the most influential predictors in Kanafar and Mansoura, respectively. In Kanafar, average yield and weight of 200 berries decreased by 21% and 22.7 g respectively in cluster 2, but in Mansoura only average yield increased by 3.7% in cluster 2. Total soluble solids and titratable acidity were not significantly affected by the shift in climate conditions at both vineyards, however total anthocyanin potential was significantly lower in Kanafar (by 114.2 mg kg-1 ) and higher in Mansoura (by 353.4 mg kg-1 ) in cluster 2. Total polyphenolic richness was only affected in Kanafar (reduction by 42 mg GAE g-1 in cluster 2). Syrah performance was more negatively affected by the changing climate conditions at Kanafar rather than Mansoura vineyards and it seems to better adapt to climate conditions of Mansoura overcoming the shift in climate that occurred after 2008 there

Laboratory Evaluation Of HMA Mixes Manufactured With Pg64-28nv And Pg64-28pm Polymer-modified Asphalt Binders

The purpose of this study was to evaluate and compare the mechanical properties of asphalt mixtures manufactured with PG64-28PM to those manufactured with PG64-28NV. Additionally, a mechanistic-empirical analysis was conducted to evaluate the impact of the two polymer-modified HMA mixtures on predicted pavement performance