Drag Reduction Using Graphene in Viscous Laminar Flow with Water and Isopropanol

America has over 2.6 million miles of pipeline for the transportation of energy products, such as liquid petroleum and natural gas. Friction is one of the main sources for energy dissipation at liquid/solid interfaces that limits the transport of a fluid through a cylindrical pipe or tube. In order to make these pipelines more efficient and enhance the flow of these materials, it is necessary to find a coating material that reduces the frictional drag. The ideal material would reduce the drag between the fluid and solid interface while being easily synthesizable on the surface. The goal of this project is to demonstrate ultra-low drag between the liquid/solid interface by exploiting the reduced kinetic friction of graphene, an allotrope of carbon in the form of a honey-comb lattice structure. Graphene has very weak van der Waals forces between layers and very weak out-of-plane bonding, which causes ultra-low kinetic friction and would lower the drag between a fluid and its container. We have successfully synthesized monolayer graphene on high copper pipe using chemical vapor deposition and investigated the fluid flow of two test liquids, water and isopropanol, through those pipes. We have not found consistent results that suggest a reduction or increase in drag in our graphene-coated samples when compared to the uncoated control pipes. Future research will provide the knowledge necessary to synthesize these materials and apply them on an industrial scale

Food habits and trophic niche overlap of the wolf Canis lupus, L. 1758 and the red Fox vulpes vulpes (L. 1758) in a Mediterranean mountain area

Les régimes alimentaires du Loup Canis lupus et du Renard roux Vulpes vulpes ont été étudiés par analyse de leurs fèces au Parc National des Abruzzes, dans l'Apennin central (Italie), de 1981 à 1983. Les Ongulés sauvages et domestiques constituent l'essentiel du régime du Loup, et l'augmentation de la consommation des espèces sauvages (renforcées par réintroductions dans le parc) ne s'est pas accompagnée d'une diminution de la prédation sur les espèces domestiques. Les ordures ne constituent pas un élément important du régime du Loup dans la région considérée; ce n'est qu'entre décembre 1981 et mai 1982 qu'elles atteignirent 10,25 % du régime (en volume

Plant wax biomarkers in human evolutionary studies

Abstract Plant wax biomarkers are an innovative proxy for reconstructing vegetation composition and structure, rainfall intensity, temperature, and other climatic and environmental dynamics. Traditionally used in earth sciences and climate studies from ?off-site? ocean and lake records, biomarker research is now incorporated in archeology and paleoanthropology to answer questions relating to past human-environment interactions and human evolution. Biomarker research is generating new and exciting information on the ecological context in which Homo and its closest relatives evolved, adapted, and invented stone tool technologies. In this review, we examine plant wax biomarkers and their use in reconstructing past plant landscapes and hydroclimates. We summarize the applications of plant wax molecular proxies in archeological research, assess challenges relating to taphonomy, consider the role of modern plant ecosystems in interpreting ancient habitats, and examine case studies conducted at key paleoanthropological locations in eastern and southern Africa and Europe.1 Introduction 2 Complementary addition to multi-proxy studies 3 Taphonomic normalization 4 Establishing the plant wax ecology of modern african soil 5 Plant waxes shed light on multiple aspects of human evolution 5.1 Orbital forcing and hominin ecology 5.2 Plant landscape variability 5.3 Hominin targeted ecotones 5.4 Activity areas in caves and rock shelters 6 Where do we go from here

Microhabitat variability in Human Evolution

Climate variability and hominin evolution are inextricably linked. Yet, hypotheses examining the impact of large-scale climate shifts on hominin landscape ecology are often constrained by proxy data coming from off-site lake and ocean cores and temporal offsets between paleoenvironmental and archaeological records. Additionally, landscape response data (most commonly, records of vegetation change), are often used as a climate proxy. This is problematic as it assumes that vegetation change signifies global or regional climate shifts without accounting for the known non-linear behavior of ecological systems and the often-significant spatial heterogeneity in habitat structure and response. The exploitation of diverse, rapidly changing habitats by Homo by at least two million years ago highlights that the ability to adapt to landscapes in flux had emerged by the time of our genus’ African origin. To understand ecosystem response to climate variability, and hominin adaptations to environmental complexity and ecological diversity, we need cross-disciplinary datasets in direct association with stratified archaeological and fossil assemblages at a variety of temporal and spatial scales. In this article, we propose a microhabitat variability framework for understanding Homo’s adaptability to fluctuating climates, environments, and resource bases. We argue that the exploitation of microhabitats, or unique ecologically and geographically defined areas within larger habitats and ecoregions, was a key skill that allowed Homo to adapt to multiple climates zones and ecoregions within and beyond Africa throughout the Pleistocene.Introduction Microhabitat variability - Identifying Microhabitat Variability Environmental and climate variability and human evolution Ecosystem resilience in face of climate change Microhabit at variability and human evolution - Microhabitat Variability at Oldupai Gorge: A Case Study Expanding the microhabitat variability framework Conclusio

Ancient great wall building materials reveal paleoenvironmental Changes in Northwestern China

Plant material used in the construction of segments and beacon towers of the ancient Great Wall in northwestern China contain untapped potential for revealing paleoenvironmental conditions. Here, we characterize the molecular preservation and stable carbon and nitrogen isotope compositions of common reeds (Phragmites) collected from Great Wall fascines dated to the Han Dynasty in today’s Gansu and Xinjiang provinces using a combination of chromatographic techniques and isotope analyses. Our data demonstrates that ancient reeds were harvested from local habitats that were more diverse than exist today. The isotope data also capture differential rates of environmental deterioration along the eastern margin of the Tarim Basin, leading to the intense evaporative stress on modern plants. This study demonstrates the wealth of environmental and climate information obtainable from site-specific organic building material of ancient walls, which have received considerably less attention than the iconic brick and stone masonry walls of the later Ming Dynasty.Introduction Results - Py-GC-MS Analysis - Lipid Concentration and Distribution - Bulk Carbon and Nitrogen Isotope Analysis Discussion - Differential Rates of Environmental Deterioration - Temperature and the Diversity of Ancient Phragmites Populations - Archaeological Significance of the Great Wall in Northwestern China Conclusions Methods - Site Locations and Sampling - Plant Biomolecular Composition -- Molecular Composition -- Plant Wax Lipids - Bulk Carbon and Nitrogen Isotope Analysis -- Carbon -- Nitroge

Evaluación experimental de la hidrodinámica y procesos de mezcla en la confluencia de los ríos Tercero y Saladillo

En este trabajo se presenta la caracterización experimental in situ de la hidrodinámica y patrones de mezcla de una confluencia natural de flujos de diferente densidad de dos ríos de mediana escala. Para ello se implementaron y optimizaron modernas técnicas experimentales de medición de velocidad de flujo (Perfiladores de corriente acústicos Doppler – ADCP), visualización del flujo, y medición de conductividad del agua. Con ADCP se determinaron la batimetría, y los parámetros hidráulicos globales mientras que con el uso de técnicas de visualización del flujo se pudo identificar el tamaño de la zona de estancamiento y las características de la capa de mezcla. Además, con GPS diferencial de alta precisión se relevó la pendiente de la superficie del agua. Finalmente, mediante la medición de la conductividad eléctrica y temperatura del agua de los flujos de aproximación y en la interfase de mezcla aguas abajo de la confluencia, se determinó la longitud requerida para la mezcla transversal completa de ambas masas de agua. Los resultados obtenidos en este trabajo permitieron evaluar el patrón hidrodinámico y de mezcla más conveniente para modelar los principales procesos presentes en confluencias fluviales como la estudiada que presenta naturaleza compleja. La presencia de flujos de diferente densidad genera una mayor complejidad en los patrones hidrodinámicos y de mezcla observados.Fil: Herrero, Horacio. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Estudios y Tecnología del Agua; Argentina.Fil: García, Carlos M. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Estudios y Tecnología del Agua; Argentina.Fil: Patalano, Antoine. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Estudios y Tecnología del Agua; Argentina.Fil: Szupiany, Ricardo. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas. Centro Internacional de Estudios de Grandes Ríos; Argentina.Ingeniería Civi

An innovative approach to designing digital health solutions addressing the unmet needs of obese patients in Europe

According to the World Health Organization (WHO), the worldwide obesity rate has tripled since 1975. In Europe, more than half of the population is overweight and obese. Around 2.8 million people die each year worldwide as a result of conditions linked to being overweight or obese. This study aimed to analyze the policies, approaches, and solutions that address the social and health unmet needs of obese patients, at different levels, in order to simulate the definition of an integrated approach, and to provide and share examples of innovative solutions supporting health promotion, disease prevention, and integration of services to improve the collaboration between the different health and care stakeholders involved across the country and in the lives of obese patients. A collaborative approach involving various levels of government and regional experts from different European countries was applied to identify, explore, and evaluate different aspects of the topic, from the innovation perspective and focusing on a European and a regional vision. Currently, people prefer more foods rich in fats, sugars, and salt/sodium than fruits, vegetables, and fiber. This behavior leads to a significant negative impact on their health-related quality of life. Changes in healthcare systems, healthy policy, and approaches to patient care and better implementation of the different prevention strategies between all the stakeholders are needed, taking advantage of the digital transformation of health and care. Such changes can support obese patients in their fight against an unhealthy lifestyle and at the same time reduce healthcare costs

Preservation of plant-wax biomarkers in deserts:implications for Quaternary environment and human evolutionary studies

Analysis of plant‐wax biomarkers from sedimentary sequences can enable past environmental and hydrological reconstruction and provide insights into past hominin adaptations. However, biomarker preservation in desert contexts has been considered unlikely given the sparse nature of the vegetation within the landscape. Here we evaluate the preservation of n‐alkanes and fatty acids collected from four depositional sequences associated with archaeological contexts in the Nefud Desert, Saudi Arabia, and the Thar Desert, India. Pleistocene and Holocene samples were selected to understand the effects of age on preservation. The results of molecular distribution patterns and indices, particularly the high carbon preference index and average chain length, show the preservation of plantwax biomarkers in both the Holocene and Pleistocene desert sequences, while δ13C values and organic content provide insights into the vegetation contributing to the plant‐wax organic pool. This study provides a baseline for understanding human–environment interactions and for reconstructing changes in arid land habitats of relevance to hominins during the Quaternary.peer-reviewe