bluuebunny/crossref_metadata_2025_split huggingface dataset:
Geochemistry of High-Molecular Weight Dimethylalkanes
Authors: Kashirtsev V.A. , Dzyuba O.S. , Nikitenko B.L. , Kostyreva E.A. , Ivanova I.K. , Shevchenko N.P. 
Published: August 2021

Abstract
—The homologous series of high-molecular weight dimethylalkanes (HMWDMAs) with either odd- or even-numbered carbon chains in the range from C19–20 to C30–31 have been identified in organic matter from recent and partially lithified deposits of Siberia and the Russian Platform by chromatography–mass spectrometry. The first homologous series is represented by even-numbered 3,4-HMWDMAs followed by the alternation of odd-numbered 3,5-HMWDMAs, even-numbered 3,6-HMWDMAs, and odd-numbered 3,7-HMWDMAs. The most abundant are 3,7-dimethylalkanes. The microbial origin of high-molecular weight dimethylalkanes is the most likely explanation for their presence in the fossil organic matter. The precursors of HMWDMAs might have been tetra- and diether lipids of archaea and bacteria. It is assumed that HMWDMAs and other immature hydrocarbons from great depths (SV-27 and SG-6 superdeep boreholes) result from the decomposition of asphaltenes, which occluded the related compounds inside their structure during the early stages of generation and carried them unchanged throughout the “oil window”.
The Vendian–Cambrian Cyclometric Stratigraphic Scale for the Southern and Central Siberian Platform
Authors: Mel’nikov N.V. 
Published: August 2021

Abstract
—The general Vendian stratigraphic scale of Siberia, with the uncertain age of the Vendian base ranging from 600 to 630– 640 Ma in most of recent publications, remains worse constrained than the Cambrian scale, in which the boundaries of epochs and stages have been well defined. However, the imperfect classical stratigraphic division has been compensated by data on the cyclicity of the Vendian–Cambrian sedimentary section. The Vendian stratigraphy of the Siberian Platform and the related deposition history with cycles of sedimentation and gaps, as well as the hierarchy of sedimentation processes, can be inferred from the succession of alternating clastic, carbonate, and salt units. The cyclicity of geologic processes and their recurrence are attributed to periodic oscillatory motions of the crust. The ranks of these motions correlate with the cyclicity of sedimentary strata, including regocyclites, nexocyclites, and halcyclites separated by gaps. Each Vendian long-period oscillatory motion begins with a regocyclite and ends with a regional-scale gap. The Cambrian section includes one pre-Mayan regional gap at the end of the early Cambrian long-period cycle. Cambrian regocyclites are composed of carbonate subformations and formations in the lower part and alternating salt and carbonate beds in the upper part.
Fluid Geodynamics of Deeply Buried Zones of Oil and Gas Accumulation in Sedimentary Basins
Authors: Abukova L.A. , Volozh Yu.A 
Published: August 2021

Abstract
—We substantiate certain ideas concerning the key role of fluid-geodynamic processes in the evolvement of hydrocarbon accumulations at great depths, in the Earth’s crust. The presented geodynamic model of oil and gas accumulation is based on updated ideas of the structure of the Earth’s tectosphere, which includes plate, preplate, and folded complexes, and the model makes clearer the spatial scale of the organic matter transformation into hydrocarbons of the oil series. In the bottom layers of the Earth’s crust, we predict the existence of a special stagnation type of water-drive systems with the following distinguishing features: (a) different scales of manifestation, from local to regional; (b) a limited nature of processes of water exchange with the external environment; (c) absence of persistent drainage horizons (beds and interbeds); (d) alignment of hydrodynamic potentials in terms of depths and laterals; and (e) increasing importance of lithohydrochemical and organic-chemistry factors in the development of the void space of the fluid host medium. In their inner space, systems with difficult water exchange can exercise control over the evolvement and preservation of autoclave hydrocarbon systems for a long time, the key feature of the autoclave systems being spatial coincidence (localization) of the processes of oil and gas generation and accumulation. We assume that, in the settings of all-round compression, hydrodynamic instability, and no drainage, occurrence of productive zones is controlled by foci of low pore (reservoir) pressures rather than by local hypsometric highs. We present results of prediction of the development of water-drive stagnation systems occurring in the subsalt deposits of the Caspian depression within the unpenetrated areas of the subsalt profile. For the sedimentary cover at large (and ultralarge) depths, a prediction of reservoir pressures was made, which can be regarded as a necessary component in any prediction of oil and gas potential, since it makes it possible to contour some new (previously unknown) industrially significant zones of hydrocarbon accumulation.
Getting Your Perforations in a Line Can Mean More-Productive Fracturing
Authors: Rassenfoss Stephen 
Published: August 2021

Want more production from a shale well? Consider lining up the perforations.
A handful of speakers at the recent SPE Hydraulic Fracturing Technology Conference talked about improved fracturing results with oriented perforating—shooting the holes at the same place in the casing, often the top.
This breaks from designs that arranged the holes in a helical pattern with each charge angled 60° from the previous one.
“We did see indications we are getting better production from oriented perforating,” said Blake Horton, senior completions engineer for Ovintiv (SPE 204177).
Production gains were also reported by ConocoPhillips which compared production from similar wells with and without oriented perforating. The analysis was designed to filter out differences in the geology, drilling, and completions.
It concluded the value of the added production far exceeded the $20,000-per-well cost of installing the assembly, including a weight bar to tilt the perforating guns into position.
“That’s less than the undiscounted value of 400 barrels of oil. An internal study indicated that ConocoPhillips improved estimated ultimate recovery (EUR) by a minimum of 5% when using high-side-oriented perforating,” said Dave Cramer, senior engineering fellow at ConocoPhillips and an early advocate for the method.
“For an initial choked flow rate of 1,000 B/D, the payout on investment is 10 days or less,” he said.
Ovintiv declined to provide a number, but Horton said ConocoPhillips’ estimate is within Ovintiv’s range based on similar comparisons of wells with and without oriented perforating.
That number is at the low end of the estimates offered in discussions about oriented perforating performance at the conference. Higher estimates are questioned by those who doubt the test results can be sustained when the method is scaled up. What was certain is the number of users is rising and includes names such as Shell and Chevron.
“We found that oriented perforating definitely helps to treat all the clusters,” said Jon Snyder, a staff completion engineer for ConocoPhillips who presented the paper, adding, “by oriented perforating we mean that when we are perforating, we aim for the high side of the wellbore” (SPE 204203).
When Horton polled the audience at a recent talk, more than half of the respondents said they were using gun systems designed to orient the perforating charges at a target angle.
“A year from now, few people will not be doing oriented perforating; the advantages of it are clear,” Cramer said. He has been promoting the idea within the company for years with mixed acceptance.
Technology Focus: Decarbonization (July 2021)
Authors: Jenvey Nigel 
Published: August 2021

Have you noticed the change in the oil and gas industry over the past year with its engagement in carbon management, decarbonization, and net-zero-emissions targets?
Policy support and technology advances in alternative energies have delivered massive cost reduction in renewables more quickly, and to a greater degree, than expected. Over the past few years, more of the world’s capital has been spent on electricity than oil and gas sup-ply, and more than half of all new energy-generation capacity is now renewable.
Some elements of society, therefore, have suggested that this is the beginning of the end for the fossil-fuel sector and call for investors to turn away from oil and gas and “leave it in the ground.”
In more than a century of almost continuous change, however, the oil and gas industry has a long track record of innovative thinking, creative solutions, and different business models. SPE papers and events that covered decarbonization during the past year show that a wide variety of solutions already exist that avoid, reduce, replace, offset, or sequester greenhouse gas (GHG) emissions. It is clear, therefore, that decarbonization technologies will now be as important as 4D seismic, horizontal wells, and hydraulic fracturing. That is why we now bring you this inaugural Technology Focus feature dedicated to decarbonization.
The experience and capability of the entire JPT community in decarbonization is critical. Please enjoy the following summary of three selected papers on the role of natural gas in fuel-switching; carbon capture, use, and storage (CCUS); and hydrogen technologies that deliver the dual challenge of providing more energy with less GHG emission.
There are many ways to engage in the SPE decarbonization efforts in the remainder of 2021. Regional events have addressed CCUS, hydrogen, geothermal, and methane. There is also the new SPE Gaia sustainability program to enable and empower all members who wish to engage in the alignment of the future of energy with sustainable development. The Gaia program has an on-demand library of materials, including an existing series on methane, and upcoming similar events on other energy transition, natural capital and regeneration, and social responsibility priorities. Get involved through your SPE section or chapter or contact your regional Gaia liaison to find out what Gaia programming you can support or lead at www.spe.org/en/gaia.
An Experimental Study of Steam-Solvent Coinjection for Bitumen Recovery Using a Large-Scale Physical Model
Authors: Sheng Kai , Okuno Ryosuke , Al-Gawfi Abdullah , Nakutnyy Petro , Imran Muhammad , Nakagawa Kazunori 
Published: August 2021

Summary
In this paper, we present a solvent-assisted steam-assisted gravity drainage (SA-SAGD) experiment with multicomponent solvent (i.e., condensate) using a large physical model. The sandpack for the experiment had a porosity of 0.33 and a permeability of 5.6 darcies in the cylindrical pressure vessel that was 1.22 m in length and 0.425 m in internal diameter. The sandpack was initially saturated with 93% Athabasca bitumen and 7% deionized water. The main objective of this research was to study the in-situ thermal/compositional flow and produced bitumen properties in SA-SAGD with condensate.
After the preheating of the sandpack for 24 hours, SA-SAGD with 2.8-mol% condensate was performed at 50 cm3/min (cold-water equivalent) at 3500 kPa for 3 days. The experimental data of production, injection, and temperature distribution were recorded. Also, 10 samples of produced oil were taken and analyzed for density and asphaltene content. The sandpack was excavated after the experiment to analyze the asphaltene content in the remaining oil at different locations. A numerical simulation model was calibrated based on the data of material balance and temperature distribution, and it was validated with properties of the produced and excavated samples. The simulation model used fluid models based on experimental data of viscosities, densities, and bubblepoints for four condensate/bitumen mixtures.
Results showed that SA-SAGD was efficient in bitumen recovery with a cumulative steam-to-oil ratio (SOR) that was two to three times smaller than that in SAGD using the same physical model. Detailed analysis of the calibrated simulation model indicated that SA-SAGD enabled the steam chamber to expand more efficiently with a smaller amount of water throughput than SAGD. Volatile solvent components tended to remain in the chamber, and the condensed solvent components acted as a miscible carrier for bitumen components. The analysis further showed that the more efficient oil recovery in SA-SAGD occurred with predominantly cocurrent flow of oil and water near the chamber edge. SA-SAGD recovered a larger amount of asphaltene components (i.e., less in-situ upgrading) than SAGD likely because of its lower chamber temperature, shorter production period, and enhanced local displacement efficiency.
Deciphering The Molecular Pathogenesis Behind Neurological Manifestations of SARS-CoV-2 And Drug Repurposing, A Systems Biology Approach
Authors: mozafar maryam , Mirmotalebisohi Seyed Amir , Sameni Marzieh , Dehghan Zeinab , Khazaei-Poul Yalda , Sepehrizadeh Zargham , Faramarzi Mohammad Ali , Shahverdi Ahmad Reza , zali hakimeh 
Published: August 2021

Abstract
Introduction: As the COVID-19 pandemic spreads worldwide, reports about the neurological complications of SARS-CoV-2 are excessively increasing. However, there is still insufficient high-throughput data on neuronal cells infected with SARS-CoV-2 to help predict its neural pathogenesis. HCoV-OC43 is another member of the beta coronavirus family that has confirmed neuro-invasive effects and has available neural omics data. This study predicts the critical genes, biological processes, and pathways mediating in SARS-CoV-2 neurological manifestations using a systems biology approach.Method: We retrieved raw data related to SARS-CoV-2 and HCoV-OC43 infections from gene expression omnibus datasets (GSE147507 and GSE13879 respectively). We constructed gene regulatory networks for both infections, detected significant regulatory motifs by FANMOD software, and created their subnetworks. We also constructed PPI networks and identified the MCODE clusters. In the intersection of merged subnetworks of two viruses, the most critical genes were verified in GRN & PPI networks. We drug-repurposed for the selected target genes and performed the functional enrichment analysis using DAVID and String databases.Results: Some of the top KEGG pathway results included NF-kappa B, Toll-like receptor, NOD-like receptor, MAPK, and Neurotrophin signaling pathways. The most essential identified genes included IL6, TNF, HOXA5, POU2F2, ITGB3, STAT1, YY1, E2F6, ESR1, FOXO3, FOXO1, MEF2A, ATF3, ATF4, DDIT3, TCF4, BCL2L2, and BMP4. These genes were also involved in mechanisms of other viral infections of the nervous system. This study repurposes nine medicines with effects on COVID-19 neurological complications. Some of the repurposed drugs were previously registered in clinical trials for COVID-19 treatment.Conclusion: We recommended some identified crucial genes and medications to investigate further their potential role in treating COVID-19 neurological complications.
Geospatial Analysis of Land Use/Land Cover Dynamics on Lake Abaya-Chamo Wetland in Southern Rift-Valley of Ethiopia
Authors: Zekarias Tariku , Govindu Vanum , Kebede Yechale , Gelaw Abren 
Published: August 2021

Abstract
Wetlands worldwide and in Ethiopia have long been subject to severe degradation due to anthropogenic factors. This study was aimed at analyzing the impact of land use/cover dynamics on Lake Abaya-Chamo wetland in 1990–2019. Data were acquired via Landsat TM of 1990, ETM + of 2000, and OLI of 2010 and 2019 images plus using interview. Unsupervised and supervised classifications (via ERDAS14 and ArcGIS10.5) were applied to detect land use/cover classes. Normalized difference vegetation index, normalized difference water index, change matrix model and Kappa coefficients were used for analysis of the land use/cover dynamics in the lake-wetland. It was found that forest; water, shrub land, agricultural land, settlement and swamp area were the main land use/cover classes. While ‘settlement’ and ‘water body’ of the lake-wetland increased at progressively increasing magnitudes of changes in three periods within 1990–2019, ‘shrub land’ and ‘swamp’ declined at progressively increasing magnitudes of loss in the same periods. The NDWI result revealed that ‘swamp’ area shrank by 48.9% (2,991 ha) due to siltation-led expansion of the lake-water in three decades. Siltation, rapid population growth-led expansion of settlement and irrigation-based farming were the main drivers of the land use/cover dynamics and degradation of the lake-wetland. Thus, consistent mapping and integrated actions should be taken to curb the threats on the sustainability of the lake-wetland in Southern Ethiopia.
Weakening affinity of SUS304 asperities to die surface with TiN coating for preventing delayed cracks in deep-drawn cups
Authors: Tan Chin Joo , Phoo Yoong Hau 
Published: August 2021

Abstract
SUS304 stainless steel has strong affinity to carbon tool steel surfaces. Therefore, the flow of material in the flange portion during the deep drawing process is retarded, leading to increase in amount of wall thicknening along the cup edge and rising risk for delayed cracks. In this paper, TiN coating is applied to the drawing die surface to weaken the affinity. Under elevated blank holding forces (BHF), the experimental results showed that the crack-free BHF range for the TiN coated and the uncoated dies are 5~10 kN and 12 kN, respectively. The entire BHF range for successful drawn cups formed with the coated die are crack-free. The crack-free BHF magnitude is successfully lowered and the range is enlarged with the coating. Crack-free cups having large elongated height and low amount of wall thickening along the cup edge are formed. The weak affinity is evidenced by the low estimated coefficient of friction (COF) obtained from a FE simulation model based on the Coulomb’s law of friction. In contrast, the estimated COF of the uncoated die is high even at the low BHF due to the strong affinity. Therefore, delayed cracks are observed under BHF range of 7~11 kN. At BHF of 12 kN, wear fragments are formed in the boundary layer as a result of the continuous polishing of the SUS304 asperities by the uncoated die asperities. The COF is sharpyly decreased due to the smooth relative movement of contacting surfaces facilitated by the particles and the formation of cracks is prevented. However, the segments tend to penetrate into the SUS304 surface under excessive BHF of 13kN and above. The relative motions of the segments are prohibited, resulting in the reformation of the cracks.
Analytical Solution of 1D Advection-Dispersion Equation In Finite Groundwater Reservoir With Spatially Dependent Dispersivity And Two Inputs Sources With Source-Sink Term Impact
Authors: TJOCK-MBAGA Thomas , Abiama Patrice Ele , Ema'a Jean Marie Ema'a , Ben-Bolie Germain Hubert 
Published: August 2021

Abstract
This study derives an analytical solution of a one-dimensional (1D) advection-dispersion equation (ADE) for solute transport with two contaminant sources that takes into account the source term. For a heterogeneous medium, groundwater velocity is considered as a linear function while the dispersion as a nth-power of linear function of space and analytical solutions are obtained for and . The solution in a heterogeneous finite domain with unsteady coefficients is obtained using the Generalized Integral Transform Technique (GITT) with a new regular Sturm-Liouville Problem (SLP). The solutions are validated with the numerical solutions obtained using MATLAB pedpe solver and the existing solution from the proposed solutions. We exanimated the influence of the source term, the heterogeneity parameters and the unsteady coefficient on the solute concentration distribution. The results show that the source term produces a solute build-up while the heterogeneity level decreases the concentration level in the medium. As an illustration, model predictions are used to estimate the time histories of the radiological doses of uranium at diﬀerent distances from the sources boundary in order to understand the potential radiological impact on the general public.
MiR-219-5p is Involved In The Proliferation, Migration And Invasion of Oral Cancer Through SOX5 Regulation
Authors: Mao Rui , Zhou Ting , He Ying , Dong Xiao-Han , Xiyang Yan-Bin , Chen Bo , Ton Jun 
Published: August 2021

Abstract
Purpose Oral cancer has the characteristics of rapid progression, wide invasion and poor prognosis, which induces higher mortality in the patients. At present, there are about 300 thousand new cases of oral cell carcinoma worldwide. Particularly, the incidence rate of oral cancer in China is relatively high. Therefore, it urgently needs to understand the pathogenesis of oral cancer and molecular mechanisms underlying. Abnormal regulation of miR-219-5p is present in various types of cancer. However, the relationship between miR-219-5p and its targets in oral cancer has not been well evaluated. Methods Western blotting and Quantitative RT-PCR were used to detect the e CCK8 assay,Conlony formation assay and Transwell assays .The interaction between SOX5 and miR-219-5p and oral cancer was confirmed using dual-luciferase reporter assays.Result This study aims to investigate the possible roles of miR-219-5p and its potential target gene, SOX5, in the progress of oral cancer. Our data showed that the high miR-219-5p and low SOX5 expression levels were associated with improved survival rates in patients. miR-219-5p level was negatively correlated with the expression of SOX5. Genetic analysis and luciferase assay revealed that the miR-291-5p regulated SOX5 expression by targeting the 3'-UTR region of SOX5 mRNA. Functionally, we confirmed that miR-219-5p mimics inhibited SOX5 expression and suppressed the proliferation, colony formation ability, invasion and migration of oral cancer cells, SCC4 and SCC9. In contrast, inhibition of miR-219-5p increased SOX5 levels and promoted the vitality and mobility of oral cancer cells. Furthermore, special siRNA targeting SOX5 partially neutralized the effects of miR-219-5p inhibitor. Conclusions This study demonstrates that miR-219-5p may inhibit the proliferation, migration and invasion of oral cancer by targeting the expression of SOX5, which provided novel candidates for clinic prognosis and/or therapy.