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The Weak Hyperedge Tenacity of the Hypercycles
Get PDFGraphs play an important role in our daily life. For example, the urban transport network can be represented by a graph, as the intersections are the vertices and the streets are the edges of the graph. Suppose that some edges of the graph are removed, the question arises how damaged the graph is. There are some criteria for measuring the vulnerability of graph; the tenacity is the best criteria for measuring it. Since the hypergraph generalize the standard graph by defining any edge between multiple vertices instead of only two vertices, the above question is about the hypergraph. When a hyperedge is omitted from hypergraph, we have two kinds of deletion: strong deletion and weak deletion. Weak hyperedge deletion just deletes the connection between the vertices in the hyperedge and the vertices became in the hypergraph. In this paper, we obtain the tenacity of hypercycles by weak hyperedge deletion
Ionic Liquids in Biomass Processing
No full textThe ionic liquids have emerged as new solvents and catalysts for processing biomass to value added chemicals and fuels. This review will present the recent developments in applications of ionic liquids in lignocellulosic biomass pretreatments, depolymerization, biodiesel synthesis, dehydration of carbohydrates to renewable feedstock chemicals as well as further transformations of biomass derived feedstocks such as furfural, 5-hydroxymethylfurfural and levulinic acid to value added chemicals. In addition, the recycling of ionic liquids used in biomass processing is also discussed in the review
Solid acid catalyzed aldol dimerization of levulinic acid for the preparation of C10 renewable fuel and chemical feedstocks
No full textThe acid catalyzed condensation of levulinic acid was studied using a series of solid acid catalysts: Amberlyst-15, SiO2-SO3H, Dowex50WX8, Carbon-SO3H, TiO2-SO3H, Al2O3-SO3H, H3PW12O40, and Nb2O5.H2O under neat conditions at 110–130 °C. The major dimerization product was identified as tetrahydro-2-methyl-5,γ-dioxo-2-furanpentanoic acid. In addition, four minor products were identified as diastereomeric pairs of 3-(2-methyl-5-oxo-tetrahydrofuran-2-yl)-4-oxopentanoic acid and 3-acetyl-2-methyl-tetrahydro-5-oxo-2-furanpropanoic acid by spectroscopic and computational methods. A mechanism is proposed to explain the formation of five dimerization products where the major product is formed via the aldol condensation of C5 enol form of levulinic acid and four minor products are arising from the aldol condensations C3 enol form of levulinic acid. The highest total yield 56% was obtained with the use SiO2-SO3H as the solid acid catalyst and the reminder of the mass balance was unreacted levulinic acid. The SiO2-SO3H catalyst could be recycled four times with some loss in catalytic activity
Evaluation of phytotoxicity of three organic amendments to collard greens using the seed germination bioassay
No full textSmall-scale vegetable and fruit crop producers in the USA use locally available commercial organic fertilizers and soil amendments recycled from municipal and agricultural wastes. Organic soil amendments provide crops with their nutrient needs and maintain soil health by modifying its physical, chemical, and biological properties. However, organic soil amendments might add unwanted elements such as toxic heavy metals or salts, which might inhibit crop growth and reduce yield. Therefore, the objective of this study was to evaluate phytotoxicity of three commercial organic amendments, chicken manure, milorganite, and dairy manure, to collard greens using the seed germination bioassay and chemical analysis of the organic amendments. The seed germination bioassay was conducted by incubating collard greens seeds to germinate in 1:10 (w/v) organic amendment aqueous extracts. Results of this work identified phytotoxic effects of chicken manure and milorganite, but not dairy manure, to collard greens. Potentially phytotoxic chemicals such as copper, zinc, nickel, and salts were also higher in chicken manure and milorganite compared to dairy manure. In particular, nickel in chicken manure and milorganite aqueous extracts was 28-fold and 21-fold, respectively, higher than previously reported toxic levels to wheat seedlings. The results demonstrate the need for more research on phytotoxicity of commercial organic soil amendments to ensure their safe use in vegetable and fruit crop production systems
Potential impact of climate change on irrigation water requirements for some major crops in the northern high plains of Texas
No full textFuture irrigation water requirements (IWRs) for different crops will be affected by the variation of rainfall and evapotranspiration that are projected to be impacted by future climate change. Thus, there is a need to investigate the potential impact of climate change and increasing climate extremes on the sustainability of agricultural production systems. The main goal of this study is to analyze the potential impact of climate change on IWRs for four major crops (corn, cotton, sorghum and winter wheat) in the Northern High Plains of Texas (NHPT). Specific objectives are to (i) generate and analyze projected daily climate data based on different Global Climate Models (GCMs) and (ii) assess the potential impact of climate change on IWRs and other water balance components of four major crops. Daily gridded climate data from the National Center for Environmental Prediction (NCEP) Climate Forecast System Reanalysis (CFSR) for the 1981 to 2010 period were used to represent observed historical daily climate data. We applied the statistical downscaling model Long Ashton Research Station Weather Generator (LARS-WG) to generate projected daily climate data at each grid cell (approximately 38 × 38 km) within the study region. The climate data for three future periods, that is, the 2020s, 2050s, and 2090s, were generated using outputs from 15 GCMs under three emission scenarios (B1, A1B, and A2). The hydrologic parameters of the major soil types in the study region were derived from the Soil Survey Geographic Database (SSURGO). Irrigation water requirements and major water budget components for all grid cells were calculated using the Irrigation Management System (IManSys) model based on crop specific growth parameters, site-specific soil hydrological properties, irrigation system efficiency, and long-term daily climate data (current and future climate scenarios). Monthly temperature and reference evapotranspiration were projected to increase; however, annual precipitation was expected to decrease in the future projection periods. Thus, gross irrigation requirements (GIRs) of all four crops, with an irrigation system efficiency of 75%, were assumed to increase (2.08-3.77% in the 2020s, 6.23-9.25% in 2055s and 6.81-19.52% in 2090s), threatening the possibility of serious groundwater depletion and long-term sustainable agriculture in this region. Further work is needed to predict crop yield responses to potential climate change scenarios for these different future periods
Sperm cellular and nuclear dynamics associated with bull fertility
No full textThe objective of this study was to ascertain cellular characteristics and the dynamics of the sperm chromatin proteins protamine 1 (PRM1) and protamine 2 (PRM2) in the sperm of Holstein bulls having a different fertility status. Important sperm variables were analyzed using computer-assisted sperm analysis (CASA). Sperm membrane, acrosome status, DNA integrity were also assessed using propidium iodide (PI), fluorescein isothiocyanate conjugated to Arachis hypogaea (FITC-PNA), and acridine orange (AO) followed by flow cytometry. In addition, abundances of PRM1 and PRM2 were analyzed using flow cytometry experiments. Differences in sperm decondensation capacity were assessed in bulls of varying fertility using a decondensation assay. As determined using CASA, average pathway velocity, amplitude of lateral head displacement and straightness were different (P \u3c 0.05) for sperm from high and low fertility bulls. There, however, were no differences between the high and low fertility bulls for characteristics of sperm plasma membrane, acrosome, and DNA integrity (P \u3e 0.05). Relative abundances of PRM1 and PRM2 in sperm from the high and low fertility bulls were inversely related (P \u3c 0.0001). Percentages of decondensed sperm were different between high and low fertility bulls (P \u3c 0.0001) and total numbers of decondensed sperm were greater in low fertility bulls than high fertility bulls (R2 = 0.72). Results of the present study are significant because molecular and morphological phenotypes of sperm that were detected affect fertility in livestock species
REVIEW: Potential of water buffalo in world agriculture: Challenges and opportunities
No full textPurpose: The purpose of this review was to provide a summary of the current agriculture determinants of economically important traits, and solutions for challenges in water buffalo production to maximize benefits for both producers and consumers. Sources: A comprehensive literature search was conducted on the current state of knowledge of water buffalo published in high-quality peer-reviewed journals. The search revealed important progress in generation of knowledge about uses, economically important traits, challenges, and science-based solutions of water buffalo. Molecular determinants of key economically important traits such as longevity, disease resistance, milk production and quality, meat production and quality, growth and development, heat stress, and fertility are deciphered. Synthesis: Water buffalo are important sources of food and fiber for the ever-increasing global human population. Drought-adapted water buffalo provide meat, and highly nutritious milk used to make cream, butter, yogurt, and cheese. Despite valuable contributions to agriculture and human well-being, there are current and emerging challenges and opportunities. High resolution sequencing of breeds and comprehensive annotation of the genomes are not yet available. In addition, there is a lack of fundamental knowledge about economically important traits including longevity, disease resistance, milk production and quality, meat production and quality, growth and development, heat tolerance, and fertility. With the advances in both basic science and technology, the gaps in the knowledge in these areas can be tackled with innovative research and systems biology approaches. In addition, the power of comparative animal and functional genomics can be harnessed to fill in the gaps. The core elements of sustainable solutions include education, innovative, transformative and translational research, and technology transfer. Conclusions and Applications: Knowledge about the fundamental biology of water buffalo gives the power to improve sustainable, efficient, and profitable production. Although a considerable amount of information is available, providing new knowledge about the economically important traits will enable precision farming in water buffalo agriculture. New data and knowledge generated through the genome to phenome will uncover essential molecular, cellular, and physiological markers for marker-assisted selection and breeding to enhance the efficiency of reproduction and production as well as product quality. Future studies using systems physiology approaches will advance the science and technology for water buffalo. These new frontiers are important for empowering the next generation of animal scientists and the public as well as for food security on the global scale
Machine Learning Assisted Wireless Big Data Processing In The 5G ERA
No full textThe proliferation of smart mobile devices and applications requiring high data rates has resulted in phenomenal mobile data growth around the world, with no growth in the scarce spectral resources. The demand for these scarce spectral resources will increase with the introduction of fifth generation (5G) wireless communication systems. Considering the 5G use cases, ranging from the Broadband Access, Internet of Things (IoT), Public Safety and Autonomous Driving, leading to a multi-tiered heterogeneous wireless architecture, further strain on these limited resources is expected. 5G is being designed to operate across a vast range of frequency bands, spanning licensed, shared, and unlicensed spectrum. Therefore, an intelligent and efficient use of scarce spectrum is highly essential. This study examines performance gain from applying machine learning to smart radio terminals, resulting in better spectral efficiency. Specifically, the dissertation examines application of machine learning to spectrum awareness using Spectrum Data (Radio Frequency (RF) traces) to improve spectral efficiency. A machine learning based spectrum awareness model trained using historical spectrum data can learn and make accurate prediction of a complicated coexistence scenarios in heterogeneous networks, such as deciding if the spectrum is idle (available for use) or whether to coexist with spectrum occupant or seek for other spectrum if number of users will degrade performance or a licensed user is present. Traditional spectrum awareness method can only decide whether the spectrum is idle or busy, this will not ensure the spectral efficiency we seek in future wireless networks due to missed transmission opportunities. Future work will focus on application of novel machine learning models to address complexity challenges in future wireless communication resource allocation optimization such as vehicular communication, exploiting other wireless big data such as user mobility data and network management data
Local View Based Connectivity Search in Online Social Networks
No full textOne of the challenges in social media research is that, often times, researchers or third parties could not obtain the massive of data collected by a limited number of \u27big brothers\u27 (e.g., Facebook and Google). In this paper, we shed light on leveraging social network topological properties and local information to effectively conduct search in Online Social Networks (OSN). The problem we focus on is to discover the reachability of a group of target people in an OSN, particularly from the perspective of a third-party analyst who does not have full access to the OSN. We developed effective and efficient detection techniques which demand only a small number of queries to discover people\u27s connections (e.g. friendship) in the OSN. After conducting experiments on real-world data sets, we found that our proposed techniques perform as well as the centralized detection algorithm, which assumes the availability of the global information in the OSN