bluuebunny/crossref_metadata_2025_split huggingface dataset:
Estimation of the optimal direction of the horizontal borehole relative to the minimum and maximum formation stress
Authors: Bosikov I I , Egorova E V , Karpikov A V 
Published: May 2022

Abstract
The article discusses the analysis and assessment of the optimal direction of the horizontal wellbore and its spatial location relative to the minimum and maximum reservoir stresses play a significant role in the design of an operation to create multiple hydraulic fractures. Theoretically, two cases are possible: the horizontal wellbore is located strictly in the direction of maximum horizontal stress; the horizontal wellbore is located strictly in the direction of the minimum horizontal stress. As a conclusion based on the hydraulic fracturing design, the well productivity factor was calculated and compared for longitudinal and transverse fractures; longitudinal fractures have a clear advantage. According to the presented calculation, the hydraulic fracturing method will have advantages in a horizontal well in a highly permeable reservoir. The hydraulic fracturing method will increase the vertical permeability. According to the presented calculation, the hydraulic fracturing method will have advantages in a horizontal well in a highly permeable reservoir. The hydraulic fracturing method will increase the vertical permeability and unite the disparate parts of the reservoir. The hydraulic fracturing method will increase the vertical permeability and unite the disparate parts of the reservoir, which will make it possible to more efficiently develop the reserves of the Neocomian deposits in the field.
Investigation of the influence of the drive shaft speed on the characteristics of a submersible pump when pumping out a gas-liquid mixture
Authors: Odintsov A A , Musinskii A N , Ostrovskii V G 
Published: May 2022

Abstract
The article presents the results of small size ESP (electrical submersible pump) tests at a speed of 6000-8500 rpm in the presence of free gas at the inlet to the device. The submersible centrifugal pump is quite sensitive to the presence of free gas in the pumped gas-liquid mixture. Depending on the amount of free gas, the actual characteristics of the pump are deformed, and at a certain gas content, the pump stops supplying the gas-liquid mixture. Stable operation of the ESP is carried out with a free gas content at the pump inlet ranging from 5% to 25%, depending on the pump size. There are several ways to deal with gas in wells operated by ESP: from running the pump into the zone where the intake pressure ensures optimal pump flow and stable operation to the use of separating and dispersing devices at the intake. Results represent pump flow characteristics along with different inlet free gas contents.
Analysis and forecasting of the success of hydraulic fracturing treatment in the selection of candidate wells
Authors: Anisimov V V , Mukhametshin V Sh , Valeev A I 
Published: May 2022

Abstract
At present, a huge part of oil and gas reserves are hard-to-recover, that is, they are located in deposits being classified as low-permeability reservoirs. A detailed analysis of the success of previously conducted hydraulic fracturing treatment of reservoirs in the wells of the explored production facility, as well as the methodology approbation for the assessment and selection of design candidate wells for further HFT in this field are considered in the paper.
Telemetry system based on fiber-optic gyroscopes
Authors: Melekhin A A , Riabokon E P , Krivoshchekov S N 
Published: May 2022

Abstract
The article presents a telemetry system for monitoring the bit trajectory during well drilling. Fiber-optic closed-loop gyroscopes are the main sensitive element in the telemetry system. The gyroscopes allow determining the azimuth and zenith angles of the well with a high accuracy exceeding most magnetometers. There is no need to use the expensive non-magnetic steels in the body of the telemetry system and non-magnetic drill pipes in the drill string. Fiber-optic closed-loop gyroscopes allow using the telemetry system when drilling near the casing of adjacent wells and magnetized rocks. An inertial navigation system is installed in the developed telemetry system as a measuring unit containing three angular velocity sensors and three accelerometers mounted rigidly. The sequence and results of simulation of a hydraulic link for data transmission from the bottom of the well to the top are described. Pilot tests of the telemetry system were carried out at well No. 450 of the Tatsuksinskoye field. The obtained values of the spatial intensity of the borehole curvature in depth are close in values to the directional survey data for the borehole. The trajectory obtained during the lift is close to the trajectory gathered from directional survey data.
Influence of oil structures on the component composition of free gases of potash reservoirs at the BPPU-4 mine field of PJSC “Uralkali”
Authors: Papulov A S , Andreyko S S , Ivanov O V 
Published: May 2022

Abstract
The influence of oil structures on the content of heavy hydrocarbon gases in the component composition of free gases in the rocks of the overlying silvinite formations is considered. There is an assumption about the influence of reef formations on the overlying sedimentary deposits and the development of sub-vertical cracks, through which heavy hydrocarbon gases can penetrate into the overlying potash layers. The aim of the study is to study the relationship between the nature of the distribution of heavy hydrocarbon gases and geological disturbances and the subsequent prediction of the gas-dynamic situation during the development of potash reservoirs. The method consists of drilling holes into the roof of the mine, sealing the hole with a sealer, and then taking gas from the sealed part to the sampler and analyzing it on a gas chromatograph. The highest values of heavy hydrocarbon gases were determined for the Bc, AБ and KpII formations at the BPPU-4 mine field of PJSC Uralkali.
Impact of hydraulic fracturing on the creation of highly permeable channels within the Earth’s interior
Authors: Khalikova K M , Almukhametova E M , Gutorov A Y 
Published: May 2022

Abstract
in modern times hydrocarbon production in fields with hard-to-recover reserves is actively being implemented. This trend is caused by the depletion of conventional reserves, which increases every year of operation. In Russia, most of the hard-to-recover reserves belong to deposits with low-permeability channels and deteriorated reservoir properties. The cost-effective utilization of such subsoil resources is only possible using special technologies that can increase well productivity. One of the most commonly used technologies is hydraulic fracturing (HFT). This study analyzed the impact of HFT on the creation of highly permeable channels as a stimulation method. The methodology for the selection of well candidates for HFT was identified, its effectiveness and practical significance were evaluated.
Improvement of operational efficiency of high water-cut oil wells
Authors: Raupov I R , Milic J 
Published: May 2022

Abstract
This paper describes a new algorithm for selecting candidate wells for water shut-off works. A new comprehensive methodology for the selection of candidate wells for water shut-off technology is proposed, consisting of 4 stages, where wells with excessive water cut are identified. The reasons for the water cut are determined, and the effectiveness of water shut-off technology on a potential candidate well is substantiated and predicted. The proposed method has been tested by the example of two wells in terrigenous reservoirs of a gas-oil field.
One-pot hydrothermal synthesis of Co–Ni hexacyanoferrate nanocuboids on Ni-foam as efficient catalysts for oxygen evolution and urea oxidation reactions
Authors: Reddy Bommireddy Purusottam , Suh Youngsuk , Park Si-Hyun 
Published: May 2022

Abstract
Recently, considerable research has been conducted on Prussian blue analogues (PBAs), a type of metal-organic framework (MOF) material, as novel electrocatalysts for oxygen evolution reactions (OERs) and urea oxidation reactions (UORs). In the present work, considering Co–Ni hexacyanoferrate (CoxNi1−xHCF) as a PBA, CoxNi1−xHCF nanocuboids with different Co and Ni compositions were synthesized on Ni foam (NF) by hydrothermal synthesis. Further, their application toward OER and UOR catalytic activity was studied. The synthesized CoxNi1−xHCF:NF composites with high catalytic activity and conductivity exhibited superior catalytic performance for the OERs and UORs. The CoxNi1−xHCF:NF composite electrodes exhibited a lower overpotential (η) of 334 mV with a lower Tafel slope of 72 mV dec−1 for the OER catalytic activity and a lower potential of 1.38 V with a lower Tafel slope of 50 mV dec−1 for the UOR catalytic activity. It was observed that low charge transfer resistance, high electrochemically active surface area, and availability of Co3+ ions are major factors contributing to the OER activity. The presence of oxidative Ni2+ species contributed significantly to the UOR activity. Overall, the present study elucidates the binder-free CoxNi1−xHCF:NF electrodes as stable and high-performance OER and UOR catalysts and provides pathways for designing advanced PBA catalysts.
Accurate parametrization revealing an extremely low disorder in polymer field-effect transistors
Authors: Romanjek Krunoslav , Charbonneau Micaël , Kim Chang-Hyun 
Published: May 2022

Abstract
In this paper, a robust self-consistent parameter extraction method is applied to high-performance p-type printed polymer field-effect transistors. Simultaneous extraction of contact resistance and intrinsic channel mobility with their full gate-voltage dependence is achieved through an analytically reinforced transmission-line method. The proposed method yields a minimum width-normalized contact resistance of 12 kΩ cm and a maximum hole mobility of 1.9 cm2 V−1 s−1. Moreover, the gate-voltage-dependent mobility is interpreted in the framework of trap-and-release transport through double-exponential density of states, unveiling a disorder energy near the transport orbital as low as 29 meV.
Evaluation of Mycobacterium Avium Complex Pulmonary Disease Treatment Completion and Adherence to ATS/IDSA Guidelines
Authors: Ku Jennifer H , Henkle Emily , Carlson Kathleen F , Marino Miguel , Brode Sarah K , Marras Theodore K , Winthrop Kevin L 
Published: May 2022

Abstract

Background
Nontuberculous mycobacteria are environmental organisms that cause infections leading to chronic, debilitating pulmonary disease, among which Mycobacterium avium complex (MAC) is the most common species.

Methods
We described patterns of macrolide-based multidrug antibiotic therapies for MAC pulmonary disease (MAC-PD) in US Medicare beneficiaries with bronchiectasis between January 2006 and December 2014. MAC therapy was defined as a multidrug regimen containing a macrolide plus ≥1 other drug targeting MAC-PD (rifamycin, ethambutol, fluoroquinolone, or amikacin) prescribed concomitantly for &gt;28 days.

Results
We identified 9189 new MAC therapy users, with a mean age (standard deviation) of 74 (6 years) at the start of therapy; 75% female and 87% non-Hispanic white. A guideline-based regimen (a macrolide, ethambutol, and rifamycin, with or without amikacin) was prescribed for 51% of new MAC therapy users at treatment start, of whom 41% were continuing guideline-based therapy at 6 months, and only 18% at 12 months. Of all new MAC therapy users, by 18 months only 11% were still receiving MAC treatment, 55% had discontinued therapy, and 34% were censored owing to death or the end of the study period.

Conclusions
Overall, nearly half of new MAC therapy users were prescribed a non–guideline-recommended macrolide-based therapy, including regimens commonly associated with promoting macrolide resistance. Treatment discontinuation was common, and once discontinued, only a few beneficiaries resumed therapy at a later time. Our study adds important data to the current literature on treatment patterns for MAC-PD among older US populations. Future research should examine treatment patterns using more contemporary data sources.
Pharmacological cardioversion of supraventricular tachycardia in pregnancy during continuous electrophysiological foetal monitoring: a case report
Authors: Francinetti Audrey , Vullings Rik , Dewals Wendy , Jochems Lisbeth 
Published: May 2022

Abstract

Background
Maternal tachycardia is the most frequently occurring cardiac complication during pregnancy. Often administration of drugs is required as a treatment. The drug of choice is intravenously administered adenosine because it is considered safe, though there are limited studies regarding safety for the foetus with the use of adenosine.

Case summary
We report a conversion of maternal atrio-ventricular (AV) nodal reentry tachycardia during pregnancy with the use of intravenous adenosine whilst continuous electrophysiological foetal monitoring. Four seconds after the maternal conversion, the foetal tracing suggests the presence of a ventricular extrasystole or a transient AV block.

Discussion
This case report illustrates that the administration of adenosine intravenously during pregnancy could have an effect on the foetal conduction system. Therefore, further investigation to assess the electrophysiological effect of adenosine on the foetal electrocardiogram seems required.
Modeling Advance Oak Reproduction at Landscape Scale: The Relative Importance of Abiotic and Biotic Factors
Authors: Rittenhouse Joshua W , Leites Laura P 
Published: May 2022

Abstract
Establishing advance oak reproduction in the understory of mature oak forests before an overstory removal is critical to regenerate mixed-oak forests (Quercus spp.). Many studies have been conducted at the stand scale; however, studies at landscape scale can be particularly useful to guide silvicultural management investments. We developed a model of advance reproduction abundance at landscape scale using inventory, climate, topography, and soils data from ninety-seven mixed-oak forests located in Pennsylvania, USA. A negative binomial model was used to predict the abundance of oak seedlings between 15.2 and 91.4 cm in height and with a root collar diameter of 0.64 to 1.9 cm (established oak seedlings). This model had a Nagelkerke’s pseudo R2 of 58%. Deviance partitioning methods indicate that climate and overstory influence explain similar proportions of total deviance, but climate contributes a higher proportion of nonoverlapping information (22% versus 18%). Overstory basal area of two common oak species were positively associated with seedling abundance, whereas biotic stressors were negatively correlated. Biotic stressors showed considerable overlap with information provided by climate and overstory influences. The results of this study provide a reference to guide silvicultural management at a landscape scale.
Best Management Practices, Estimated Erosion, Residual Woody Debris, and Ground Cover Characteristics Following Biomass and Conventional Clearcut Harvests in Virginia’s Mountains
Authors: Garren Austin M , Bolding M Chad , Barrett Scott M , Aust W Michael , Coates T Adam 
Published: May 2022

Abstract
Water quality best management practices (BMPs) developed for conventional forest harvests may be adequate for biomass harvests, yet quantitative data is lacking. This study compared estimated erosion, operational feature areas, BMP implementation rates, ground cover characteristics, and downed woody debris quantities following biomass and conventional harvests in the mountains of Virginia. Haul roads on biomass harvests had significantly higher estimated erosion rates (P = 0.064) and masses (P = 0.045) than conventional harvests, but conventional harvests had higher erosion contributions from skid trails (P = 0.089) and averaged more estimated erosion mass overall, despite being significantly smaller in size (P = 0.054). There was significantly less area in heavy slash (P = 0.076) and lower estimated mass of residual downed woody debris (P = 0.001) on biomass sites than conventional sites (10.98 and 27.95 tons/ac, respectively). Site-wide BMP implementation scores (P = 0.041), streamside management zones (SMZs) (P = 0.024), and skidding (P = 0.063) were significantly higher on biomass sites than conventional sites. BMP implementation scores were significant predictors of estimated erosion rates (P &lt; 0.001, R2 = 59%), indicating that adequate levels of existing water quality BMPs are effective for erosion control on both conventional and biomass harvests.
An Inverse Growth Curve Representation of the Clutter-Jones Stand Survival Model
Authors: Wang Mingliang , Montes Cristian R , Bullock Bronson P , Zhao Dehai 
Published: May 2022

Abstract
The Clutter-Jones (CJ) stand survival model has been widely used for the projection of the reduction in trees per unit area in a forest stand over time. To better understand this well-recognized model, we introduced a varying-parameter formulation as an alternative to its original difference equation form, where plot-specific effects are presented explicitly. This new parameterization turns out to be a type of Richards (generalized logistic) equation with its independent variable age log-transformed, which might be termed “log-Richards” (LR) and falls into the category of the generalized algebraic difference approach (GADA) models. Under the LR GADA representation, a half-reduction age, at which half of the trees in a stand die, may be examined to improve stand survival simulation. The new reformulation provides an inverse growth curve modeling viewpoint of stand survival over time. It may motivate one to derive new survival models directly from existing growth equations that allow for generating inverse growth curves, complementary to the commonly used differential equation method in developing stand mortality models.
Study Implications: The Clutter-Jones stand survival model plays an important role in southern pine plantation management as a component of whole-stand modeling systems. This study introduces a varying-parameter formulation as an alternative to its original difference equation form, providing an inverse growth curve modeling viewpoint of stand survival over time.
Genome sequences of 24 Aspergillus niger sensu stricto strains to study strain diversity, heterokaryon compatibility, and sexual reproduction
Authors: Seekles Sjoerd J , Punt Maarten , Savelkoel Niki , Houbraken Jos , Wösten Han A B , Ohm Robin A , Ram Arthur F J 
Published: May 2022

Abstract
Mating-type distribution within a phylogenetic tree, heterokaryon compatibility, and subsequent diploid formation were studied in 24 Aspergillus niger sensu stricto strains. The genomes of the 24 strains were sequenced and analyzed revealing an average of 6.1 ± 2.0 variants/kb between Aspergillus niger sensu stricto strains. The genome sequences were used together with available genome data to generate a phylogenetic tree revealing 3 distinct clades within Aspergillus niger sensu stricto. The phylogenetic tree revealed that both MAT1-1 and MAT1-2 mating types were present in each of the 3 clades. The phylogenetic differences were used to select for strains to analyze heterokaryon compatibility. Conidial color markers (fwnA and brnA) and auxotrophic markers (pyrG and nicB) were introduced via CRISPR/Cas9-based genome editing in a selection of strains. Twenty-three parasexual crosses using 11 different strains were performed. Only a single parasexual cross between genetically highly similar strains resulted in a successful formation of heterokaryotic mycelium and subsequent diploid formation, indicating widespread heterokaryon incompatibility as well as multiple active heterokaryon incompatibility systems between Aspergillus niger sensu stricto strains. The 2 vegetatively compatible strains were of 2 different mating types and a stable diploid was isolated from this heterokaryon. Sclerotium formation was induced on agar media containing Triton X-100; however, the sclerotia remained sterile and no ascospores were observed. Nevertheless, this is the first report of a diploid Aspergillus niger sensu stricto strain with 2 different mating types, which offers the unique possibility to screen for conditions that might lead to ascospore formation in A. niger.
Histone variant H2A.Z promotes meiotic chromosome axis organization in Saccharomyces cerevisiae
Authors: Chigweshe Lorencia , MacQueen Amy J , Holmes Scott G 
Published: May 2022

Abstract
Progression through meiosis is associated with significant reorganization of chromosome structure, regulated in part by changes in histones and chromatin. Prior studies observed defects in meiotic progression in yeast strains lacking the linker histone H1 or variant histone H2A.Z. To further define the contributions of these chromatin factors, we have conducted genetic and cytological analysis of cells undergoing meiosis in the absence of H1 and H2A.Z. We find that a spore viability defect observed in strains lacking H2A.Z can be partially suppressed if cells also lack histone H1, while the combined loss of both H1 and H2A.Z is associated with elevated gene conversion events. Cytological analysis of Red1 and Rec8 staining patterns indicates that a subset of cells lacking H2A.Z fail to assemble a proper chromosome axis, and the staining pattern of the synaptonemal complex protein Zip1 in htz1Δ/htz1Δ cells mimics that of cells deficient for Rec8-dependent meiotic cohesion. Our results suggest a role for H2A.Z in the establishment or maintenance of the meiotic chromosome axis, possibly by promoting the efficient chromosome cohesion.
Fine-tuning acetyl-CoA carboxylase 1 activity through localization: functional genomics reveals a role for the lysine acetyltransferase NuA4 and sphingolipid metabolism in regulating Acc1 activity and localization
Authors: Pham Trang , Walden Elizabeth , Huard Sylvain , Pezacki John , Fullerton Morgan D , Baetz Kristin 
Published: May 2022

Abstract
Acetyl-CoA Carboxylase 1 catalyzes the conversion of acetyl-CoA to malonyl-CoA, the committed step of de novo fatty acid synthesis. As a master regulator of lipid synthesis, acetyl-CoA carboxylase 1 has been proposed to be a therapeutic target for numerous metabolic diseases. We have shown that acetyl-CoA carboxylase 1 activity is reduced in the absence of the lysine acetyltransferase NuA4 in Saccharomyces cerevisiae. This change in acetyl-CoA carboxylase 1 activity is correlated with a change in localization. In wild-type cells, acetyl-CoA carboxylase 1 is localized throughout the cytoplasm in small punctate and rod-like structures. However, in NuA4 mutants, acetyl-CoA carboxylase 1 localization becomes diffuse. To uncover mechanisms regulating acetyl-CoA carboxylase 1 localization, we performed a microscopy screen to identify other deletion mutants that impact acetyl-CoA carboxylase 1 localization and then measured acetyl-CoA carboxylase 1 activity in these mutants through chemical genetics and biochemical assays. Three phenotypes were identified. Mutants with hyper-active acetyl-CoA carboxylase 1 form 1 or 2 rod-like structures centrally within the cytoplasm, mutants with mid-low acetyl-CoA carboxylase 1 activity displayed diffuse acetyl-CoA carboxylase 1, while the mutants with the lowest acetyl-CoA carboxylase 1 activity (hypomorphs) formed thick rod-like acetyl-CoA carboxylase 1 structures at the periphery of the cell. All the acetyl-CoA carboxylase 1 hypomorphic mutants were implicated in sphingolipid metabolism or very long-chain fatty acid elongation and in common, their deletion causes an accumulation of palmitoyl-CoA. Through exogenous lipid treatments, enzyme inhibitors, and genetics, we determined that increasing palmitoyl-CoA levels inhibits acetyl-CoA carboxylase 1 activity and remodels acetyl-CoA carboxylase 1 localization. Together this study suggests yeast cells have developed a dynamic feed-back mechanism in which downstream products of acetyl-CoA carboxylase 1 can fine-tune the rate of fatty acid synthesis.