bluuebunny/crossref_metadata_2025 huggingface dataset:
SAGD Operation in Interbedded Sands With Application of Horizontal Multistage Fracturing; Reservoir Engineering Aspects
Authors: Saeedi Majid , Settari A. Tony
Published: September 2016

Steam assisted gravity drainage (SAGD) is a widely used thermal recovery method. During steam injection in interbedded sands, the portion of the deposits above the vertical permeability barriers is likely not recoverable with current practices. This paper examines the reservoir engineering aspects of using multistage fracturing in SAGD operations in interbedded sands such as IHS, where the vertical permeability barriers impede the gravity drainage process.

Assuming that the permeability barriers can be targeted and broken with vertical hydraulic fracturing treatments before steaming, it is very likely that the steam can pass through the shales, effectively heat the otherwise isolated oil, and eventually drain it. The flow mechanism and the recovery response of a fractured SAGD well are discussed and it is shown that the suggested process has a great potential to improve production rate and recovery factor. The desired fracture properties and expected production rates are obtained by using both analytical and numerical reservoir engineering techniques. Some quick assessment criteria are also introduced.

Analytical equations to estimate the SAGD peak rate were derived for various sand-shale sequences and fracture configurations. The analytical equations can be used for quick evaluation of the fracturing potential in such SAGD wells. A correction factor was suggested to compensate for simplifying assumptions.

Through numerical simulation, a matrix of sensitivity cases was developed with variation of key parameters such as fracture permeability, fracture half-length, fracture spacing and orientation. It was shown that fractures with short half-length but high conductivity are required for the process to work. Using the sensitivity results, an optimum range for key fracturing parameters was determined. Furthermore, a dimensionless fracture conductivity criterion was used as a general design criterion. The issues around fracturing design and sand-shale geomechanics are presented in a separate paper.

The multistage fracturing technique in horizontal wells was first used in tight and shale gas plays, and different variations of the field execution of this technique are now widely available. To our knowledge, this work is the first detailed examination of the potential of multistage fracturing for improving SAGD in interbedded pays. It is shown that, if this technique can be combined with in-situ steam operations, some of the problems with steaming interbedded pays can be addressed. In particular, it is shown that the recovery can be substantially improved to be comparable to clean sands. However, the use of multistage fracturing in SAGD process also introduces unique execution challenges that require thorough analysis and design, which were the focus of the companion paper (Saeedi and Settari, 2016).
Combined Technology of Weak Gel Flooding assisting Thermal Huff and Puff Enhances Oil Recovery for Offshore Heavy Oil Field
Authors: Pan Guangming , Chen Jianbo , Zhang Caiqi , Liu Dong , Wu Jintao , Li Hao , Fang Zhou , Qu Jifeng , Zhang Junting
Published: September 2016

South part of NN reservoir, locating at Bohai Bay of China, has geology characteristics of flat structure, complex oil-water contact system. The formation oil viscosity reaches as high as 413~741mPa•s. At initial production stage, daily oil of vertical well and horizontal well reached 21m3/d and 35m3/d, respectively. Due to complex oil-water relationship and high formation oil viscosity, oil production rate of whole reservoir decreased from 0.6% to 0.3% after one year.

Combinatorial development techniques including thermal huff-puff and weak gel flooding have been optimized for further enhancing oil recovery. Considering the platform space limit, thermal huff-puff uses multiple thermal fluid(nitrogen, dioxide, hot water) instead of conventional steam. Twelve new horizon wells have been carried out in the pure oil zone for thermal huff-puff pilot. Until now, there have been twelve wells which completing the first cycle huff-puff, and six wells have completed the second cycle. Meanwhile, in order to keep the formation pressure and reduce the channeling risk, selected three high water-cut production wells were changed into injection wells for weak gel flooding pilot.

After carried out combinatorial development techniques, the rate of oil production of whole reservoir has increased from 0.3% to 0.7%. Thermal huff-puff heated oil during the huff process then decreases the formation oil viscosity, and finally increasing the production ability of horizon wells in the puff process. Compared with natural energy production, peak oil production and periodic oil production of thermal production respectively increases to 3 times and 1.6 times in the first cycle. Weak gel flooding increases viscosity of the injected fluid and reduces the difference of water-oil mobility ratio, the average resistance coefficient of three injection wells reaches as high as 1.74. Around the three injection wells, there are nine wells increasing the oil production, and incremental oil production for single well has reached 0.45×104m3~2.12×104m3 in the past few years. Also, there is a positive synergistic effect between thermal huff-puff and weak gel flooding. The artesian flow days of one thermal well extends 76 days in the help of weak gel flooding.

Our experiences show that such combinatorial development techniques are effective for enhancing oil recovery of heavy oil fields and meet the demand of high speed development for offshore oil fields.
Numerical Modeling of Multiphase Flow Toward Fractured Horizontal Wells In Heterogeneous Nanoporous Formations
Authors: Holy R. W. , Ozkan E.
Published: September 2016

This paper presents an anomalous diffusion based approach for modeling two-phase oil/water flow in fractured nanoporous media, such as that encountered in unconventional oil and gas reservoirs. Production is assumed to be from a multiply fractured horizontal well and the focus of the discussions is 1D linear flow in the region between hydraulic fractures. To account for the complexity and heterogeneity of the fractured medium, anomalous diffusion is considered in the flow domain between hydraulic fractures. To do so, the conventional Darcy phase fluxes are replaced by more general fractional flux laws which incorporate the non-local and hereditary nature of flow by means of fractional space-time phase and capillary pressure gradients. A modified IMPES scheme is derived for linear oil/water flow under specified terminal pressure production, and the impact of sub- and super-diffusion on phase rates, as well as pressure and saturation distributions across the system is studied.
Análise da mudança da vegetação nativa ocasionada pela expansão agrícola no município de Uruçuí, Piauí
Authors: Queiroz Julianna Lima , Rocha Layla Martins de Casto , Reis Adriana Saraiva dos , Sampaio João Paulo Da Silva , Sousa Willamys Rangel Nunes de , Lopes Francisco Smiley Meneses Sousa
Published: September 2016

Atualmente, a agricultura moderna no Brasil, que antes era concentrada na região Centro-Sul, difundiu-se nos estados do Nordeste. O Piauí vivenciou uma rápida ocupação do Cerrado, devido a introdução de grandes projetos de agricultura e o município de Uruçuí se destaca na produção de grãos, principalmente a soja. O objetivo dessa pesquisa foi analisar a mudança da vegetação nativa ocasionada pela expansão agrícola do município de Uruçuí por meio do sensoriamento remoto. O processo foi dividido em fases, tais como: aquisição de dados, pré-processamento, extrapolação e classificação de imagens. Foram utilizadas imagens dos anos de 2003 do satélite Landsat 5 TM e de 2013 do Landsat 8 TM. As imagens desses dois anos foram georreferenciadas e fundidas através da técnica de mosaico com o programa QGIS. Por fim, foi produzido um mapa temático área degradada, para avaliar a evolução do processo de substituição da vegetação. Os dados obtidos nesse estudo indicaram que ocorreu a evolução das áreas de lavouras de grãos no município de Uruçuí. A análise das figuras revelou a substituição da vegetação nativa da região ocasionada principalmente pela crescente expansão agrícola. É de extrema importância o monitoramento dessas grandes áreas, para que seja possível quantificar o nível de exploração e reduzir os impactos ambientais.
A adubação orgânica no cultivo da melancieira cv.Crimson sweet
Authors: Gomes Dutra Katia Otilia , Cavalcante Salatiel Nunes , Vieira Ianne Gonçalves Silva , Costa Jussara Cristina Firmino da , Andrade Raimundo
Published: September 2016

Detentora de grande importância socioeconômica, a melancieira, pode ser cultivada, principalmente, por pequenos agricultores em função do fácil manejo e do custo de produção quando comparada a outras hortaliças. O objetivo desse trabalho foi avaliar o comportamento da cultura da melancieira em sistemas orgânicos sobre os componentes de produção e a caracterização química dos frutos. O experimento foi conduzido na Estação Experimental Agroecológica do CCHA, Campus IV da UEPB, em Catolé do Rocha. Foram avaliados os efeitos de 3 fontes de matéria orgânica e 5 dosagens de biofertilizante nos componentes de produção de melancieira. O delineamento experimental utilizado foi em blocos ao acaso, num esquema fatorial 5x3, com 4 repetições. A água para suprimento da irrigação teve como fonte um aqüífero, poço amazonas próximo ao local do experimento e o método de irrigação foi por gotejamento. As variáveis analisadas foram: Número de frutos por planta; Comprimento do fruto; Perímetro do fruto; Número de sementes por fruto; Sólidos Solúveis totais (ºBrix), (pH) dos frutos, Produção por planta e Produtividade. A adubação orgânica com húmus, esterco bovino, esterco caprino e biofertilizante influenciam positivamente os componentes de produção de melancia. O esterco caprino pode substituir o esterco bovino e o húmus na adubação orgânica da melancia. A produtividade registrada para as plantas adubadas organicamente independentemente da fonte é compatível ao representado em cultivo convencional.
Surfactant‐Modified Soil Amendments Reduce Nitrogen and Phosphorus Leaching in a Sand‐Based Rootzone
Authors: Shaddox Travis W. , Kruse Jason K. , Miller Grady L. , Nkedi‐Kizza Peter , Sartain Jerry B.
Published: September 2016

United States Golf Association putting greens are susceptible to nitrogen (N) and phosphorus (P) leaching. Inorganic soil amendments are used to increase moisture and nutrient retention and may influence N and P leaching. This study was conducted to determine whether N and P leaching could be reduced using soil amendments and surfactant‐modified soil amendments. Treatments included a control (sand), sand–peat, zeolite, calcined clay, hexadecyltrimethylammonium–zeolite, and hexadecyltrimethylammonium–calcined clay. Lysimeters were filled with a 30‐cm rootzone layer of sand–peat (85:15 by volume), below which a 5‐cm treatment layer of amendments was placed. A solution of NO3–N, NH4–N, and orthophosphate‐P (2300, 2480, and 4400 μg mL−1, respectively) was injected at the top of each lysimeter, and leachate was collected using an autocollector set to collect a 10‐mL sample every min until four pore volumes were collected. Uncoated amendments, sand, and peat had no influence on NO3–N retention, whereas hexadecyltrimethylammonium‐coated amendments reduced NO3–N leaching to below detectable limits. Both coated and uncoated amendments reduced NH4–N leaching, with zeolite reducing NH4–N leached to near zero regardless of hexadecyltrimethylammonium coating. Pure sand resulted in a 13% reduction of applied orthophosphate‐P leaching, whereas peat contributed to orthophosphate‐P leaching. Surfactant‐modified amendments reduced orthophosphate‐P leaching by as much as 97%. Surfactant‐modified soil amendments can reduce NO3–N, NH4–N, and orthophosphate‐P leaching and, thus, may be a viable option for removing leached N and P before they enter surface or ground waters.

Core Ideas

Soil amendments did not reduce NO3–N leaching.

Modified soil amendments reduced NO3–N, NH4–N, and orthophosphate‐P leaching.

Zeolite was most effective at reducing NH4–N leaching.
Enabling Science Support for Better Decision‐Making when Responding to Chemical Spills
Authors: Weidhaas Jennifer L. , Dietrich Andrea M. , DeYonker Nathan J. , Ryan Dupont R. , Foreman William T. , Gallagher Daniel , Gallagher Jennifer E.G. , Whelton Andrew J. , Alexander William A.
Published: September 2016

Chemical spills and accidents contaminate the environment and disrupt societies and economies around the globe. In the United States there were approximately 172,000 chemical spills that affected US waterbodies from 2004 to 2014. More than 8000 of these spills involved non–petroleum‐related chemicals. Traditional emergency responses or incident command structures (ICSs) that respond to chemical spills require coordinated efforts by predominantly government personnel from multiple disciplines, including disaster management, public health, and environmental protection. However, the requirements of emergency response teams for science support might not be met within the traditional ICS. We describe the US ICS as an example of emergency‐response approaches to chemical spills and provide examples in which external scientific support from research personnel benefitted the ICS emergency response, focusing primarily on nonpetroleum chemical spills. We then propose immediate, near‐term, and long‐term activities to support the response to chemical spills, focusing on nonpetroleum chemical spills. Further, we call for science support for spill prevention and near‐term spill‐incident response and identify longer‐term research needs. The development of a formal mechanism for external science support of ICS from governmental and nongovernmental scientists would benefit rapid responders, advance incident‐ and crisis‐response science, and aid society in coping with and recovering from chemical spills.
Physical Soil Structure Evaluation based on Hydraulic Energy Functions
Authors: Armindo Robson André , Wendroth Ole
Published: September 2016

Core Ideas

Five indices and two hydraulic energy cumulative functions are examined to evaluate SPQ.

With these indices and functions, it is possible to assess soil structure through spatial and temporal effects.

The volumetric water content at field capacity was calculated based on a flux drainage criterion.

The script for SWRC fitting parameters and all presented indices is provided.

Qualitative analyses of physical, chemical, or biological variables are difficult and often ambiguous. Soil physical quality (SPQ) indices are not an exception to this rule. There is no unique revealing parameter or index that enables evaluating soil structure. In high‐intensity biomass production systems, SPQ indices are useful tools for management decisions because they indicate the sustainability of soil organic matter dynamics, drainage, infiltration, heat transfer, and storage processes. This work examines five energy parameters and two hydraulic energy functions for evaluating physical quality in terrestrial vegetative ecosystems. These indices are based on numerical integration of the soil water retention curve (SWRC) and on soil water content at field capacity, and they manifest the absolute aeration energy, the absolute water retention energy, the relative aeration energy, the relative water retention energy, and the relative air‐water energy. This integration technique includes the use of all points of the SWRC. A script for fitting the parameters of the van Genuchten equation and for solving all the presented indices in this work was developed and made available. The energy indices and hydraulic functions were derived and validated for SWRCs, from several German, US, and Brazilian soils under different management, comparing them with other previously published SPQ indices. Our findings reveal that the energy indices and functions can be applied to assess the energy associated with the soil physical structure.
The Directional Components of Splash Erosion at Different Raindrop Kinetic Energy in the Chinese Mollisol Region
Authors: Hu Wei , Zheng Fenli , Bian Feng
Published: September 2016

Core Ideas

Directional components of splash erosion and effects of raindrop kinetic energy were investigated.

Lateral splash erosion played a significant role in supplying detached particles to adjacent areas.

We fit equations for total and net splash erosion to rainfall physical parameters.

We used cross‐validation to test the equations.

Splash erosion is an important process of hillslope erosion. However, there is little information available in the literature to show how rainfall physical parameters affect the directional components of splash erosion. Therefore, the objectives of this study were to investigate the effects of rainfall physical parameters (rainfall intensity [RI], raindrop kinetic energy [KE], and raindrop diameter) on the directional components (upslope, lateral, downslope) of splash erosion characteristics in the Chinese Mollisol region. A specially designed soil pan, which can measure the directional components of splash erosion, was subjected to designed rainfall intensities of 50 and 100 mm h−1 and varying raindrop KE. The results showed that the total splash erosion (downslope plus upslope plus lateral splash erosion), directional components of splash erosion, and net splash erosion (downslope minus upslope erosion) on hillslopes significantly increased as RI and raindrop KE increased (p < 0.05). Furthermore, splash erosion from downslope, lateral slope, and upslope contributed 32.2, 26.3, and 14.5%, respectively, of total splash erosion. Additionally, raindrop KE and raindrop median volume diameter (D50) were the key indicators affecting both total and net splash erosion. The equations between total and net splash erosion with both parameters of raindrop KE and raindrop D50 were fitted. The cross validation results showed that the two equations had acceptable accuracy. Therefore, preventing raindrop impact by using conservation tillage methods, such as retaining crop residue or mulch cover, can effectively reduce splash erosion in the Mollisol region of Northeast China.
Dr. David Kenneth Rycroft, 7 December 1924 - 8 August 1997
Authors: Kubik Gerhard
Published: September 2016

The shocking news reached me on a bright September 1997 morning, just as we were struggling to get our suitcases through the door of our hostel at Columbia College, Center for Black Music Research, Chicago where we had had a delightful two-month period of work. Our good friend Johann Buis had arrived to take us to Oâ€™Hare airport for the flight to Europe, with a letter in his hand. The promising letter came from GROVE, London. It was by Stanley Sadie, and dated 1 September 1997. My vision blurred when I read these sentences: â€œI expect you heard the sad news of David Rycroftâ€™s death. This is very sad, and will make it more difficult for us to have the ideal coverage of South Africa that we had been aiming at.â€
Xylophone music of Uganda: theembaire of Nakibembe, Busoga
Authors: Micklem James , Cooke Andrew , Stone Mark
Published: September 2016

The amadinda and akadinda xylophone music of Buganda1 2 have been well described in the past (Anderson 1968). Good players of these xylophones now seem to be extremely scarce, and they are rarely performed in Kampala. Both instruments, although brought from villages in Buganda, formed part of a great musical tradition associated with the Kabakaâ€™s palace. After 1966, when the palace was overrun by government forces and the kingdom abolished, the royal musicians were cut off from their traditional role.
Fieldwork in Lango, northern Uganda Feb-Mar 1997
Authors: Cooke Peter
Published: September 2016

Very little academic research has been carried out into the rich and varied musical traditions of the north of the country in contrast with those of the relatively well-explored areas of Bantu-speaking southern Uganda. Yet acquaintances among the Baganda for instance, have often expressed their admiration of the attractive harp and zither music of the Acholi in the north. Less well-known are the lamellaphone-playing traditions of the same general area - notably those of the Acholi, their southern neighbours the Lango people and the Teso people (to the east of Lango). In 1968 a brief fieldwork visit to eastern Acholi had made me aware of widespread and spirited use of the lukeme (the Acholi term for their box-resonated lamellaphone) in ensembles of a dozen or more young men or boys - playing on instruments in three different sizes. Unfortunately the continuing activities of rebel groups belonging to the so-called â€˜Lordâ€™s Resistance Armyâ€™ under their leader John Kony made it quite impracticable for me to visit any part of Acholi when in February 1997 I tried recently to follow up the initial research I made some 19 years earlier.
Some music traditions of Malawi
Authors: Strumpf Mitchell
Published: September 2016

Malawi, a country of great cultural diversity, shares many of its musical traditions with neighbouring cultures in other south-east African countries, namely Tanzania, Zambia, and Mozambique, as well as with culture groups further away, the Nguni (Zulu-Swazi) cultures of South Africa, for example. As part of the UNESCO CD series Musics and Musicians of the World, UNESCO (with AUVIDIS as co-publisher and distributor) made available Music traditions of Malawi (D 8265).
Koo Nimo: a contemporary Ghanaian musician
Authors: Kaye Andrew L.
Published: September 2016

Daniel Kwabena Amponsah, known professionally as Koo Nimo, was born on October 3, 1934 in Ofoase, a village near Kumasi, capital of the Ashanti Region of modem Ghana. His mother, Akua Forkuo, was a farmer, cloth trader, homemaker, and a chorister at the local Methodist church. His father, Kwame Amponsah, was a farmer, tailor, mason, and musical amateur who played the trumpet in the Ofoase brass band.
El FSLN, “el peor de los escenarios”. Debates de la militancia feminista en el contexto preelectoral nicaragüense (2004-2006)
Authors: Lacombe Delphine
Published: September 2016

Esta contribución analiza los debates de la militancia feminista nicaragüense, ocurridos durante el año 2006. Algunos meses antes de la elección de Daniel Ortega, fue conformada una nueva organización feminista: el Movimiento Autónomo de Mujeres. Sus integrantes decidieron aliarse con el partido Movimiento de Renovación Sandinista, compartiendo con éste el objetivo prioritario de evitar la toma del poder por el Frente Sandinista de Liberación Nacional, considerado como “el peor escenario”. Este trabajo explica estos procesos y propone analizar sus consecuencias en las otras agrupaciones feministas y los significados del referente revolucionario en las divergencias estratégicas de la militancia.
Adenda: Nosedonde y El casi ciego
Authors: Galeotti Anaité
Published: September 2016

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Patrones de desarrollo en la cerámica de Naachtún, Petén, Guatemala.
Authors: Patiño Alejandro
Published: September 2016

Se presenta en este artículo un análisis de las trayectorias de desarrollo de la cerámica en el sitio Naachtún entre el Preclásico Tardío (300 a.C.-150 d.C) y el Clásico Terminal (800 d.C.-900/1000 d.C). Se argumenta que la evolución de tratamientos de superficie y catálogos de formas debe entenderse dentro del contexto de prácticas en las que los habitantes de Naachtún emplearon la manufactura y el uso de parámetros particulares para establecer y mantener activamente vínculos de afiliación con regiones específicas del Área Maya. Se apunta que ciertos episodios de la secuencia de afiliación se caracterizaron por resaltar elementos comunes presentes a lo largo de las tierras bajas a la vez que se reduce la visibilidad de idiosincrasias locales, mientras que en otros casos se resaltan singularidades en características visibles y tangibles que evocan asociaciones con sitios y áreas particulares.
Association Between Long-term Exposure to Air Pollution and Biomarkers Related to Insulin Resistance, Subclinical Inflammation, and Adipokines
Authors: Wolf Kathrin , Popp Anita , Schneider Alexandra , Breitner Susanne , Hampel Regina , Rathmann Wolfgang , Herder Christian , Roden Michael , Koenig Wolfgang , Meisinger Christa , Peters Annette ,   for the KORA-Study Group
Published: September 2016

Insulin resistance (IR) is present long before the onset of type 2 diabetes and results not only from inherited and lifestyle factors but also likely from environmental conditions. We investigated the association between modeled long-term exposure to air pollution at residence and biomarkers related to IR, subclinical inflammation, and adipokines. Data were based on 2,944 participants of the KORA (Cooperative Health Research in the Region Augsburg) F4 study conducted in southern Germany (2006–2008). We analyzed associations between individual air pollution concentration estimated by land use regression and HOMA-IR, glucose, insulin, HbA1c, leptin, and high-sensitivity C-reactive protein levels from fasting samples using multivariable linear regression models. Effect estimates were calculated for the whole study population and subgroups of individuals who did not have diabetes, had prediabetes, or had diabetes. Among all participants, a 7.9 μg/m3 increment in particulate matter of <10 μm was associated with higher HOMA-IR (15.6% [95% CI 4.0; 28.6]) and insulin (14.5% [3.6; 26.5]). Nitrogen dioxide was associated with HOMA-IR, glucose, insulin, and leptin. Effect estimates for individuals with prediabetes were much larger and highly statistically significant, whereas individuals who did not have diabetes or had diabetes showed rather weak associations. No association was seen for HbA1c level. Our results suggested an association between long-term exposure to air pollution and IR in the general population that was attributable mainly to individuals with prediabetes.
The burgeoning interest in young onset dementia: redressing the balance or reinforcing ageism?
Authors: Tolhurst Edward
Published: September 2016

Critical evaluation is undertaken of social scientific conceptualisations of dementia in relation to ageing. In response to the societal tendency to associate dementia with old age, there is a growing body of literature that seeks to explicate the particular challenges faced by younger people with the condition. While recognition of the distinctive impacts presented by dementia at different ages is crucial, an age-related conceptual model that focuses on a lifecourse divide at age 65 is problematic: it promulgates a sense that younger people with dementia have ‘‘unique’’ experiences, while dementia for older people is typical. This also reflects a societal ageism, under which concerns are focused on those situated within ‘‘productive adulthood.’’ Moreover, a straightforward chronological marker cannot adequately represent a social world shaped by significant demographic changes. A more textured appreciation of ageing and dementia is required to help articulate how distinctive experiences emerge across the lifecourse.
Feasibility Assessment of Converting Sugar Mills to Bioenergy Production in Africa
Authors: Leal Manoel , Leite João , Chagas Mateus , Da Maia Rui , Cortez Luís
Published: September 2016

World sugar production has consistently overrun demand in the past five years. Moreover, in 2017 the European Sugar Regime will expire, ending the quota system and preferential sugar prices, largely affecting small producers, particularly in Africa. Diversification emerges as an option for sugar-oriented mills. Two evident alternatives are ethanol and electricity production that allow better use of molasses and cane fibers, respectively. Molasses is the cheapest feedstock for ethanol production, while the cane fibers—in the form of bagasse—are readily available at the mill. The transition from sugar to sugar, ethanol and electricity may require substantial investment capital, yet our results show that significant progress can start at relatively small cost. In this work, we use simulations to explore the impact of ethanol and electricity production in an existing sugar mill in Mozambique. In spite of the large amounts of energy obtained from ambitious scenarios, such as Ethanol-2 and Ethanol/EE, molasses-based ethanol (Ethanol-1 scenario) seems more attractive in economical and infrastructural terms. High opportunity costs for molasses, low oil prices and enabling institutional conditions, such as mandatory blending mandates, to promote bioenergy remain a challenge.
Modelling the Effect of Diet Composition on Enteric Methane Emissions across Sheep, Beef Cattle and Dairy Cows
Authors: Bell Matt , Eckard Richard , Moate Peter , Yan Tianhai
Published: September 2016

Enteric methane (CH 4 ) is a by-product from fermentation of feed consumed by ruminants, which represents a nutritional loss and is also considered a contributor to climate change. The aim of this research was to use individual animal data from 17 published experiments that included sheep ( n = 288), beef cattle ( n = 71) and dairy cows ( n = 284) to develop an empirical model to describe enteric CH 4 emissions from both cattle and sheep, and then evaluate the model alongside equations from the literature. Data were obtained from studies in the United Kingdom (UK) and Australia, which measured enteric CH 4 emissions from individual animals in calorimeters. Animals were either fed solely forage or a mixed ration of forage with a compound feed. The feed intake of sheep was restricted to a maintenance amount of 875 g of DM per day (maintenance level), whereas beef cattle and dairy cows were fed to meet their metabolizable energy (ME) requirement (i.e., production level). A linear mixed model approach was used to develop a multiple linear regression model to predict an individual animal’s CH 4 yield (g CH 4 /kg dry matter intake) from the composition of its diet. The diet components that had significant effects on CH 4 yield were digestible organic matter (DOMD), ether extract (EE) (both g/kg DM) and feeding level above maintenance intake: CH 4 (g/kg DM intake) = 0.046 (±0.001) × DOMD − 0.113 (±0.023) × EE − 2.47 (±0.29) × (feeding level − 1), with concordance correlation coefficient ( CCC ) = 0.655 and RMSPE = 14.0%. The predictive ability of the model developed was as reliable as other models assessed from the literature. These components can be used to predict effects of diet composition on enteric CH 4 yield from sheep, beef and dairy cattle from feed analysis information.
A Novel Concentrator Photovoltaic (CPV) System with the Improvement of Irradiance Uniformity and the Capturing of Diffuse Solar Radiation
Authors: Tien Nguyen , Shin Seoyong
Published: September 2016

This paper proposes a novel concentrator photovoltaic (CPV) system with improved irradiation uniformity and system efficiency. CPV technology is very promising its for highly efficient solar energy conversion. A conventional CPV system usually uses only one optical component, such as a refractive Fresnel lens or a reflective parabolic dish, to collect and concentrate solar radiation on the solar cell surface. Such a system creates strongly non-uniform irradiation distribution on the solar cell, which tends to cause hot spots, current mismatch, and degrades the overall efficiency of the system. Additionally, a high-concentration CPV system is unable to collect diffuse solar radiation. In this paper, we propose a novel CPV system with improved irradiation uniformity and collection of diffuse solar radiation. The proposed system uses a Fresnel lens as a primary optical element (POE) to concentrate and focus the sunlight and a plano-concave lens as a secondary optical element (SOE) to uniformly distribute the sunlight over the surface of multi-junction (MJ) solar cells. By using the SOE, the irradiance uniformity is significantly improved in the system. Additionally, the proposed system also captures diffuse solar radiation by using an additional low-cost solar cell surrounding MJ cells. In our system, incident direct solar radiation is captured by MJ solar cells, whereas incident diffuse solar radiation is captured by the low-cost solar cell. Simulation models were developed using a commercial optical simulation tool (LightTools™). The irradiance uniformity and efficiency of the proposed CPV system were analyzed, evaluated, and compared with those of conventional CPV systems. The analyzed and simulated results show that the CPV system significantly improves the irradiance uniformity as well as the system efficiency compared to the conventional CPV systems. Numerically, for our simulation models, the designed CPV with the SOE and low-cost cell provided an optical power ratio increase of about 17.12% compared to the conventional CPV without the low-cost cell, and about 10.26% compared to the conventional CPV without using both the SOE and additional low-cost cell.
Inhibition of Bacterial RNase P RNA by Phenothiazine Derivatives
Authors: Wu Shiying , Mao Guanzhong , Kirsebom Leif
Published: September 2016

There is a need to identify novel scaffolds and targets to develop new antibiotics. Methylene blue is a phenothiazine derivative, and it has been shown to possess anti-malarial and anti-trypanosomal activities. Here, we show that different phenothiazine derivatives and pyronine G inhibited the activities of three structurally different bacterial RNase P RNAs (RPRs), including that from Mycobacterium tuberculosis, with Ki values in the lower μM range. Interestingly, three antipsychotic phenothiazines (chlorpromazine, thioridazine, and trifluoperazine), which are known to have antibacterial activities, also inhibited the activity of bacterial RPRs, albeit with higher Ki values than methylene blue. Phenothiazines also affected lead(II)-induced cleavage of bacterial RPR and inhibited yeast tRNAPhe, indicating binding of these drugs to functionally important regions. Collectively, our findings provide the first experimental data showing that long, noncoding RNAs could be targeted by different phenothiazine derivatives.
Efficient Hydrogenolysis of Guaiacol over Highly Dispersed Ni/MCM-41 Catalyst Combined with HZSM-5
Authors: Qiu Songbai , Xu Ying , Weng Yujing , Ma Longlong , Wang Tiejun
Published: September 2016

A series of MCM-41 supported Ni catalysts with high metal dispersion was successfully synthesized by simple co-impregnation using proper ethylene glycol (EG). The acquired Ni-based catalysts performed the outstanding hydrogenolysis activity of guaiacol. The effects of the synthesis parameters including drying temperature, calcination temperature, and metal loading on the physical properties of NiO nanoparticles were investigated through the use of X-ray diffraction (XRD). The drying temperature was found to significantly influence the particle sizes of NiO supported on MCM-41, but the calcination temperature and metal loading had less influence. Interestingly, the small particle size (≤3.3 nm) and the high dispersion of NiO particles were also obtained for co-impregnation on the mixed support (MCM-41:HZSM-5 = 1:1), similar to that on the single MCM-41 support, leading to excellent hydrogenation activity at low temperature. The guaiacol conversion could reach 97.9% at 150 °C, and the catalytic activity was comparative with that of noble metal catalysts. The hydrodeoxygenation (HDO) performance was also promoted by the introduction of acidic HZSM-5 zeolite and an 84.1% yield of cyclohexane at 240 °C was achieved. These findings demonstrate potential applications for the future in promoting and improving industrial catalyst performance.
Building IoT Applications with Raspberry Pi and Low Power IQRF Communication Modules
Authors: Calvo Isidro , Gil-García José , Recio Igor , López Asier , Quesada Jerónimo
Published: September 2016

Typical Internet of Things (IoT) applications involve collecting information automatically from diverse geographically-distributed smart sensors and concentrating the information into more powerful computers. The Raspberry Pi platform has become a very interesting choice for IoT applications for several reasons: (1) good computing power/cost ratio; (2) high availability; it has become a de facto hardware standard; and (3) ease of use; it is based on operating systems with a big community of users. In IoT applications, data are frequently carried by means of wireless sensor networks in which energy consumption is a key issue. Energy consumption is especially relevant for smart sensors that are scattered over wide geographical areas and may need to work unattended on batteries for long intervals of time. In this scenario, it is convenient to ease the construction of IoT applications while keeping energy consumption to a minimum at the sensors. This work proposes a possible gateway implementation with specific technologies. It solves the following research question: how to build gateways for IoT applications with Raspberry Pi and low power IQRF communication modules. The following contributions are presented: (1) one architecture for IoT gateways that integrates data from sensor nodes into a higher level application based on low-cost/low-energy technologies; (2) bindings in Java and C that ease the construction of IoT applications; (3) an empirical model that describes the consumption of the communications at the nodes (smart sensors) and allows scaling their batteries; and (4) validation of the proposed energy model at the battery-operated nodes.
Heart Failure in Patients with Preserved Ejection Fraction: Questions Concerning Clinical Progression
Authors: Louridas George , Lourida Katerina
Published: September 2016

Over the last two decades, important advances have been made in explaining some pathophysiological aspects of heart failure with preserved ejection fraction (HFpEF) with repercussions for the successful clinical management of the syndrome. Despite these gains, our knowledge for the natural history of clinical progression from the pre-clinical diastolic dysfunction (PDD) until the final clinical stages is significantly limited. The subclinical progression of PDD to the clinical phenotype of HFpEF and the further clinical progression to some more complex clinical models with multi-organ involvement, similar to heart failure with reduced ejection fraction (HFrEF), continue to be poorly understood. Prospective studies are needed to elucidate the natural history of clinical progression in patients with HFpEF and to identify the exact left ventricular remodeling mechanism that underlies this progression.
Operation of Thin-Film Electrolyte Metal-Supported Solid Oxide Fuel Cells in Lightweight and Stationary Stacks: Material and Microstructural Aspects
Authors: Roehrens Daniel , Packbier Ute , Fang Qingping , Blum Ludger , Sebold Doris , Bram Martin , Menzler Norbert
Published: September 2016

In this study we report on the development and operational data of a metal-supported solid oxide fuel cell with a thin film electrolyte under varying conditions. The metal-ceramic structure was developed for a mobile auxiliary power unit and offers power densities of 1 W/cm2 at 800 °C, as well as robustness under mechanical, thermal and chemical stresses. A dense and thin yttria-doped zirconia layer was applied to a nanoporous nickel/zirconia anode using a scalable adapted gas-flow sputter process, which allowed the homogeneous coating of areas up to 100 cm2. The cell performance is presented for single cells and for stack operation, both in lightweight and stationary stack designs. The results from short-term operation indicate that this cell technology may be a very suitable alternative for mobile applications.
Microfluidic-Based Multi-Organ Platforms for Drug Discovery
Authors: Rezaei Kolahchi Ahmad , Khadem Mohtaram Nima , Pezeshgi Modarres Hassan , Mohammadi Mohammad , Geraili Armin , Jafari Parya , Akbari Mohsen , Sanati-Nezhad Amir
Published: September 2016

Development of predictive multi-organ models before implementing costly clinical trials is central for screening the toxicity, efficacy, and side effects of new therapeutic agents. Despite significant efforts that have been recently made to develop biomimetic in vitro tissue models, the clinical application of such platforms is still far from reality. Recent advances in physiologically-based pharmacokinetic and pharmacodynamic (PBPK-PD) modeling, micro- and nanotechnology, and in silico modeling have enabled single- and multi-organ platforms for investigation of new chemical agents and tissue-tissue interactions. This review provides an overview of the principles of designing microfluidic-based organ-on-chip models for drug testing and highlights current state-of-the-art in developing predictive multi-organ models for studying the cross-talk of interconnected organs. We further discuss the challenges associated with establishing a predictive body-on-chip (BOC) model such as the scaling, cell types, the common medium, and principles of the study design for characterizing the interaction of drugs with multiple targets.
The Effect of Ca2+ and Mg2+ on the Dispersion and Flocculation Behaviors of Muscovite Particles
Authors: Tang Jiayan , Zhang Yimin , Bao Shenxu
Published: September 2016

The dispersion and flocculation behavior of muscovite suspensions in the presence of Ca2+ and Mg2+ are relevant for industrial processing of pre-concentrated muscovite from stone coal, a primary source of vanadium. In this study, the dispersion and flocculation behavior were investigated by means of sedimentation, zeta potential, and ion absorption experiments, as well as the force between particles and ion speciation calculations. The results indicated that the dispersion and flocculation behavior of muscovite particles without excess ions were in qualitative agreement with the classical DLVO theory. The muscovite particles aggregated mainly due to basal surface-edge interactions in acidic suspensions but were dispersed in alkaline suspension by electrostatic repulsion of the total particle surface. In acidic suspensions, the ability of muscovite to form dispersions of muscovite was increased with the decrease in the electrostatic attraction between the basal surface and the edge caused by the compression of the electric double layers withCa2+ and Mg2+. In alkaline suspension, the main adsorption form of Ca2+ and Mg2+ on muscovite surface was the ion-hydroxy complexes. The flocculation behavior of muscovite was affected by the static bridge effect of the ion-hydroxy complexes.
Chemical Composition, Antibacterial Properties and Mechanism of Action of Essential Oil from Clove Buds against Staphylococcus aureus
Authors: Xu Jian-Guo , Liu Ting , Hu Qing-Ping , Cao Xin-Ming
Published: September 2016

The essential oil of clove has a wide range of pharmacological and biological activities and is widely used in the medicine, fragrance and flavoring industries. In this work, 22 components of the essential oil obtained from clove buds were identified. Eugenol was the major component (76.23%). The essential oil exhibited strong antibacterial activity against Staphylococcus aureus ATCC 25923 with a minimum inhibitory concentration (MIC) of 0.625 mg/mL, and the antibacterial effects depended on its concentration and action time. Kill-time assays also confirmed the essential oil had a significant effect on the growth rate of surviving S. aureus. We hypothesized that the essential oil may interact with the cell wall and membrane first. On the one hand it destroys cell wall and membranes, next causing the losses of vital intracellular materials, which finally result in the bacterial death. Besides, essential oil penetrates to the cytoplasmic membrane or enters inside the cell after destruction of cell structure, and then inhibits the normal synthesis of DNA and proteins that are required for bacterial growth. These results suggested that the effects of the clove essential oil on the growth inhibition of S. aureus may be at the molecular level rather than only physical damage.
(+)-Podocarpic Acid as Chiral Template in the Synthesis of Aphidicolane, Stemodane and Stemarane Diterpenoids †
Authors: La Bella Angela , Leonelli Francesca , Migneco Luisa , Marini Bettolo Rinaldo
Published: September 2016

In this review the synthetic work in the field of aphidicolane, stemodane and stemarane diterpenoids, in which readily available (+)-podocarpic acid (4) was used as chiral template for the construction of their polycyclic structures, is described as it developed along the years. In the frame of this work (+)-podocarpic acid (4) was a very useful tool in a model study leading to the syntheses of tetracyclic ketones 7 and 8, models of key intermediates 5a and 6 in the syntheses of (+)-aphidicolin (1) and (+)-stemodin (2a), respectively. (+)-Podocarpic acid (4) was also converted into (+)-2-deoxystemodinone (2d), allowing confirmation of the stemodane diterpenoids absolute configuration, into (+)-aphidicol-15-ene (36) and into Stemodia chilensis tetracyclic diterpenoid (+)-19-acetoxystemodan-12-ol (2f), allowing confirmation of its structure. (+)-Podocarpic acid (4) was then extensively used in the work which led to the synthesis of (+)-stemar-13-ene (57) and (+)-18-deoxystemarin (3b). Finally, (+)-4 was converted into (+)-2-deoxyoryzalexin S (66), which made it possible to demonstrate that the structure of (+)-66 could not be attributed to a Chilean Calceolaria isolated diterpenoid to which this structure had been assigned.
Synthesis and Anti-HIV-1 Activity Evaluation for Novel 3a,6a-Dihydro-1H-pyrrolo[3,4-c]pyrazole-4,6-dione Derivatives
Authors: Liu Guan-Nan , Luo Rong-Hua , Zhou Yu , Zhang Xing-Jie , Li Jian , Yang Liu-Meng , Zheng Yong-Tang , Liu Hong
Published: September 2016

The search for new molecular constructs that resemble the critical two-metal binding pharmacophore and the halo-substituted phenyl functionality required for HIV-1 integrase (IN) inhibition represents a vibrant area of research within drug discovery. As reported herein, we have modified our recently disclosed 1-[2-(4-fluorophenyl)ethyl]-pyrrole-2,5-dione scaffolds to design 35 novel compounds with improved biological activities against HIV-1. These new compounds show single-digit micromolar antiviral potencies against HIV-1 and low toxicity. Among of them, compound 9g and 15i had potent anti-HIV-1 activities (EC50 < 5 μM) and excellent therapeutic index (TI, CC50/EC50 > 100). These two compounds have potential as lead compounds for further optimization into clinical anti-HIV-1 agents.
Synthesis and Cytotoxic Activity on Human Cancer Cells of Novel Isoquinolinequinone–Amino Acid Derivatives
Authors: Valderrama Jaime , Delgado Virginia , Sepúlveda Sandra , Benites Julio , Theoduloz Cristina , Buc Calderon Pedro , Muccioli Giulio
Published: September 2016

A variety of aminoisoquinoline-5,8-quinones bearing α-amino acids moieties were synthesized from 3-methyl-4-methoxycarbonylisoquinoline-5,8-quinone and diverse l- and d-α-amino acid methyl esters. The members of the series were evaluated for their cytotoxic activity against normal and cancer cell lines by using the (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT) assay. From the current investigation, structure–activity relationships demonstrate that the location and structure of the amino acid fragment plays a significant role in the cytotoxic effects. Moderate to high cytotoxic activity was observed and four members, derived from l-alanine, l-leucine, l-phenylalanine, and d-phenylalanine, were selected as promising compounds by their IC50 ranging from 0.5 to 6.25 μM and also by their good selectivity indexes (≥2.24).
Preparation, Characterization and Manipulation of Conjugates between Gold Nanoparticles and DNA
Authors: Eidelshtein Gennady , Fattal Moran , Avishai Gavriel , Kempinski Benjamin , Giannini Clelia , Kotlyar Alexander
Published: September 2016

Here we described the preparation and characterization by atomic force microscopy of dumbbell-shaped conjugates between 450 bp double-stranded DNA polymer, poly(dG)-poly(dC), and 5 nm gold nanoparticles (GNPs). We have demonstrated that the size of the nanoparticles in the conjugates can be increased in a controlled fashion. Application of the conjugates for measuring the electrical conductivity of DNA is discussed.