scholarly journals Interpretation of pressure interference tests for wells connected by a large hydraulic fracture

Author(s):  
Freddy Humberto Escobar ◽  
Erik Felipe Prada ◽  
Daniel Suescún-Díaz

AbstractShale formations are being exploited in several places around the world. Thus, an adequate characterization of such formations is recommended. In this work, two interpretation methodologies—TDS technique and conventional analysis—are implemented for determining the fracture permeability, from interference tests, between two wells connected by a large hydraulic fracture. Therefore, equations have been developed for both interpretation techniques and tested with synthetic examples. The estimated fracture permeabilities closely match the values initially used for the simulation of the tests.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nathalie Raharimalala ◽  
Stephane Rombauts ◽  
Andrew McCarthy ◽  
Andréa Garavito ◽  
Simon Orozco-Arias ◽  
...  

AbstractCaffeine is the most consumed alkaloid stimulant in the world. It is synthesized through the activity of three known N-methyltransferase proteins. Here we are reporting on the 422-Mb chromosome-level assembly of the Coffea humblotiana genome, a wild and endangered, naturally caffeine-free, species from the Comoro archipelago. We predicted 32,874 genes and anchored 88.7% of the sequence onto the 11 chromosomes. Comparative analyses with the African Robusta coffee genome (C. canephora) revealed an extensive genome conservation, despite an estimated 11 million years of divergence and a broad diversity of genome sizes within the Coffea genus. In this genome, the absence of caffeine is likely due to the absence of the caffeine synthase gene which converts theobromine into caffeine through an illegitimate recombination mechanism. These findings pave the way for further characterization of caffeine-free species in the Coffea genus and will guide research towards naturally-decaffeinated coffee drinks for consumers.


Water ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 459
Author(s):  
Ignacio Cazcarro ◽  
Albert E. Steenge

This article originates from the theoretical and empirical characterization of factors in the World Trade Model (WTM). It first illustrates the usefulness of this type of model for water research to address policy questions related to virtual water trade, water constraints and water scarcity. It also illustrates the importance of certain key decisions regarding the heterogeneity of water and its relation to the technologies being employed and the prices obtained. With regard to WTM, the global economic input–output model in which multiple technologies can produce a “homogeneous output”, it was recently shown that two different mechanisms should be distinguished by which multiple technologies can arise, i.e., from “technology-specific” or from “shared” factors, which implies a mechanism-specific set of prices, quantities and rents. We discuss and extend these characterizations, notably in relation to the real-world characterization of water as a factor (for which we use the terms technology specific, fully shared and “mixed”). We propose that the presence of these separate mechanisms results in the models being sensitive to relatively small variations in specific numerical values. To address this sensitivity, we suggest a specific role for specific (sub)models or key choices to counter unrealistic model outcomes. To support our proposal we present a selection of simulations for aggregated world regions, and show how key results concerning quantities, prices and rents can be subject to considerable change depending on the precise definitions of resource endowments and the technology-specificity of the factors. For instance, depending on the adopted water heterogeneity level, outcomes can vary from relatively low-cost solutions to higher cost ones and can even reach infeasibility. In the main model discussed here (WTM) factor prices are exogenous, which also contributes to the overall numerical sensitivity of the model. All this affects to a large extent our interpretation of the water challenges, which preferably need to be assessed in integrated frameworks, to account for the main socioeconomic variables, technologies and resources.


1997 ◽  
Vol 1 (1) ◽  
pp. 52-65
Author(s):  
Hye-Joon Yoon

Area studies, as a newly fashionable field of academic research, needs to recognize its less likely precedents if it is going to secure for itself a fresh start. The question of “desire” is relevant here because it indicates the less value-free aspects in its genealogy. As shown in Emma Bovary's embellished representation of Paris at her provincial home, an understanding of an area often reflects the particular needs and desires of the one who understands that area. Such restricted and restricting views of an area repeats itself outside the world of literary fictions, as is shown by the example of Guizot's picture of Europe in which his own country is given a privileged place as the very center of Western civilization itself. An instructive case showing the thin line between the projected desire of one who strives to know a geographical area and the scientific purity of the labor itself is further offered by Napoleon Bonaparte's heavy reliance on Orientalist scholarship in his invasion of Egypt. Moving further east from Egypt to China, we witness the denigrating remarks on China made by the great German thinkers of the past century, Hegel and Weber. Although their characterization of Chinese culture could find echoes in unbiased empirical research, they reveal all the same the trace of Europeans' desire to affirm their superiority over the supposedly inferior and false civilization of the East. Similarly, the Americans who divided the Korean peninsular at the 38th Parallel, with unquestioning confidence in their knowledge of the area and in the justice of their action, rightfully deserve their place in the tradition of Western area studies of serving the needs to dominate, control and exploit an objectified overseas territory. He assumed that words had kept their meaning, that desires still pointed in a single direction, and that ideas retained their logic; and he ignored the fact that the world of speech and desires has known invasions, struggles, plundering, disguises, ploys. From these elements, however, genealogy retrieves an indispensable restraint: it must record the singularity of events outside of any monotonous finality; it must seek them in the most unpromising places, in what we tend to feel is without history—in sentiments, love, conscience, instincts; it must be sensitive to their recurrence, not in order to trace the gradual curve of their evolution, but to isolate the different scenes where they engaged in different roles. — Michel Foucault, “Nietzsche, Genealogy, History” (Foucault 139–40).


2021 ◽  
Author(s):  
Seyhan Emre Gorucu ◽  
Vijay Shrivastava ◽  
Long X. Nghiem

Abstract An existing equation-of-state compositional simulator is extended to include proppant transport. The simulator determines the final location of the proppant after fracture closure, which allows the computation of the permeability along the hydraulic fracture. The simulation then continues until the end of the production. During hydraulic fracturing, proppant is injected in the reservoir along with water and additives like polymers. Hydraulic fracture gets created due to change in stress caused by the high injection pressure. Once the fracture opens, the bulk slurry moves along the hydraulic fracture. Proppant moves at a different speed than the bulk slurry and sinks down by gravity. While the proppant flows along the fracture, some of the slurry leaks off into the matrix. As the fracture closes after injection stops, the proppant becomes immobile. The immobilized proppant prevents the fracture from closing and thus keeps the permeability of the fracture high. All the above phenomena are modelled effectively in this new implementation. Coupled geomechanics simulation is used to model opening and closure of the fracture following geomechanics criteria. Proppant retardation, gravitational settling and fluid leak-off are modeled with the appropriate equations. The propped fracture permeability is a function of the concentration of immobilized proppant. The developed proppant simulation feature is computationally stable and efficient. The time step size during the settling adapts to the settling velocity of the proppants. It is found that the final location of the proppants is highly dependent on its volumetric concentration and slurry viscosity due to retardation and settling effects. As the location and the concentration of the proppants determine the final fracture permeability, the additional feature is expected to correctly identify the stimulated region. In this paper, the theory and the model formulation are presented along with a few key examples. The simulation can be used to design and optimize the amount of proppant and additives, injection timing, pressure, and well parameters required for successful hydraulic fracturing.


2020 ◽  
Vol 40 (6) ◽  
Author(s):  
Luciano Nobuhiro Aoyagi ◽  
Yukie Muraki ◽  
Naoki Yamanaka

Abstract Phakopsora pachyrhizi is an obligatory biotrophic fungus that causes Asian soybean rust (ASR) disease. ASR control primarily involves chemical control and the use of resistant soybean cultivars carrying an Rpp (resistance to P. pachyrhizi) gene. This study aimed to characterize the ASR resistance of three soybean Asian landraces. By screening the world core collection (WC) of soybean, which consists of 80 varieties, three landraces were identified in Southeast Asia as resistant to ASR. Genetic mapping using the F2 population derived from a cross with an ASR-susceptible variety, BRS 184, indicated that KS 1034 (WC2) has ASR resistance conferred by a single dominant resistance gene, mapped on chromosome 18, in the same region where Rpp1 was mapped previously. The BRS 184 × WC61 (COL/THAI/1986/THAI-80) F2 population, on the other hand, showed an ASR resistance locus mapped by quantitative trait locus analysis on chromosome 6, in the region where the resistance conferred by PI 416764 Rpp3 resides, with a logarithm of the odds score peak at the same position as the marker, Satt079, while the BRS 184 × WC51 (HM 39) population showed the resistance to ASR allocated between Satt079 and Sat_263 markers, also in the region where Rpp3 was mapped previously. Both WC51 and WC61 have the same infection profile as FT-2 and PI 462312 when tested against the same ASR isolate panel. These three WCs can be used in MAS programs for introgression of Rpp1 and Rpp3 and the development of ASR-resistant cultivars in the breeding program.


Author(s):  
Марина Михайловна Молчанова ◽  
Патимат Абдулаевна Лекова

Исследуется кризис вербальности контента в интернет-дискурсе, его активная визуализация, связанная с новыми открытиями в области компьютерных технологий. Цель работы - дать полиаспектную характеристику этому явлению и обозначить перспективы его влияния на речемыслительную деятельность подрастающего поколения, составляющего большую часть пользователей социальных сетей. Актуальность данной проблематики обусловлена обеспокоенностью филологической общественностью тем, что мир становится все менее лингвистическим. Новизна заключается в том, что впервые интернет-дискурс рассматривается в контексте кризиса вербальности контента. При таких темпах визуализации медиатекстов вполне вероятно обострение кризиса вербальности, последствия которого могут негативно сказаться на мыслетворческой деятельности у подрастающего поколения, которая возможна только при высокой языковой компетенции. The paper examines the crisis of content verbality in the Internet discourse, its active visualization associated with new discoveries in the field of computer technology. The aim of the work is to give a multi-aspect characterization of this phenomenon and outline the prospects of its influence on the speech-thinking activity of the younger generation, which makes up the majority of users of social networks. The relevance of this issue is due to the concern of the philological community that the world is becoming less and less linguistic. The novelty lies in the fact that for the first time Internet discourse is considered in the context of the crisis of content verbality. At such a rate of visualization of media texts, it is likely that the crisis of verbality will aggravate, the consequences of which can negatively affect the thinking activity of the younger generation, which is possible only with high linguistic competence.


Biology ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 105
Author(s):  
Olga M. Zając ◽  
Stefan Tyski ◽  
Agnieszka E. Laudy

An increase of nosocomial infections caused by Stenotrophomonas maltophilia strains has recently been observed all over the world. The isolation of these bacteria from the blood is of particular concern. In this study we performed the phenotypic and genotypic characterization of 94 S. maltophilia isolates, including isolates from patients hospitalized in a tertiary Warsaw hospital (n = 79) and from outpatients (n = 15). All isolates were found to be susceptible to trimethoprim-sulfamethoxazole and minocycline, while 44/94 isolates demonstrated a reduction in susceptibility to levofloxacin. A large genetic variation was observed among the isolates tested by pulsed-field gel electrophoresis. A clonal relationship with 100% similarity was observed between isolates within two sub-pulsotypes: the first included nine bloodstream isolates and the second involved six. Multilocus sequence typing showed two new sequence types (ST498 and ST499) deposited in public databases for molecular typing. Moreover, the presence of genes encoding ten different efflux pumps from the resistance-nodulation-division family and the ATP-binding cassette family was shown in the majority of the 94 isolates. The obtained knowledge about the prevalence of efflux pump genes in clinical S. maltophilia strains makes it possible to predict the scale of the risk of resistance emergence in strains as a result of gene overexpression.


PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e10503
Author(s):  
Jessica Wilkie ◽  
Timothy C. Cameron ◽  
Travis Beddoe

Fasciola hepatica is the causative agent of fasciolosis, an important disease of humans and livestock around the world. There is an urgent requirement for novel treatments for F. hepatica due to increasing reports of drug resistance appearing around the world. The outer body covering of F. hepatica is referred to as the tegument membrane which is of crucial importance for the modulation of the host response and parasite survival; therefore, tegument proteins may represent novel drug or vaccine targets. Previous studies have identified a profilin-like protein in the tegument of F. hepatica. Profilin is a regulatory component of the actin cytoskeleton in all eukaryotic cells, and in some protozoan parasites, profilin has been shown to drive a potent IL-12 response. This study characterized the identified profilin form F. hepatica (termed FhProfilin) for the first time. Recombinant expression of FhProfilin resulted in a protein approximately 14 kDa in size which was determined to be dimeric like other profilins isolated from a range of eukaryotic organisms. FhProfilin was shown to bind poly-L-proline (pLp) and sequester actin monomers which is characteristic of the profilin family; however, there was no binding of FhProfilin to phosphatidylinositol lipids. Despite FhProfilin being a component of the tegument, it was shown not to generate an immune response in experimentally infected sheep or cattle.


2012 ◽  
pp. 47-50
Author(s):  
Katalin Kalmár

Tourism is one of the biggest and mostly increasing branch all over the world. Since it is getting more and more significant in Hungary as well in this article I analyze the turnover of Hungarian tourism on the basis of guest nights spent on commercial lodgings. I examine its changes in time and its territorial spreading. Finally I explore the health touristic volume, because it is one of the most important touristic product of Hungary and the North Plain Region and the infrastructure based upon preserves unique opportunities both for health and wellness tourism.


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