bluuebunny/crossref_metadata_2025 huggingface dataset:
Photocatalytic Degradation of Fluoroquinolone Antibiotics in Solution
Authors: Machín Abniel , Márquez Francisco , Fontánez Kenneth , Duconge José , Cotto María , Morant Carmen , Petrescu Florian Ion Tiberiu
Published: January 2022

The photocatalytic degradation of two quinolone-type antibiotics (ciprofloxacin and levofloxacin) in aqueous solution was studied, using catalysts based on ZnO nanoparticles, which were synthesized by a thermal procedure. The efficiency of ZnO was subsequently optimized by incorporating different co-catalysts of gC3N4, reduced graphene oxide and nanoparticles of gold. The catalysts were fully characterized by electron microscopy (TEM and SEM), XPS, XRD, Raman, and BET surface area. The most efficient catalyst was 10%Au@ZnONPs-3%rGO-3%gC3N4, allowing to obtain degradations of both pollutants above 96%. This catalyst has the largest specific area, and its activity has been related to a synergistic effect, involving factors as relevant as the surface of the material and the ability to absorb radiation in the visible region, mainly produced by the incorporation of rGO and gC3N4 to the semiconductor. The use of different scavengers during the catalytic process, was used to establish the possible photodegradation mechanism of both antibiotics.
Preparation and Characterization of Multi-doped Porous Carbon Nanofibers from Carbonization in Different Atmospheres and Their Oxygen Electrocatalytic Properties Research
Authors: Wang Tao , Ola Oluwafunmilola , Niu Qijian , Lu Yuhao , Dapaah Malcom Frimpong , Cheng Liang , Wang Nannan , Zhu Yanqiu
Published: January 2022

Recently, electrocatalysts for oxygen reduction reactions (ORRs) as well as oxygen evolution reactions (OERs) hinged on electrospun nanofiber composites have attracted wide research attention. Transition metal elements and heteroatomic doping are important methods used to enhance their catalytic performances. Lately, the construction of electrocatalysts based on metal-organic framework (MOF) electrospun nanofibers has become a research hotspot. In this work, bimetallic NixCoy-ZIF nanocrystals were synthesized in an aqueous solution, followed by NixCoy-ZIF/PAN electrospun nanofiber precursors, which were prepared by a simple electrospinning method. Bimetal (Ni-Co) porous carbon nanofiber catalysts doped with nitrogen, oxygen, and sulfur elements were obtained at high-temperature carbonization treatment in different atmospheres (Ar, Air, and H2S), respectively. The morphological properties, structures, and composition were characterized by SEM, TEM, SAED, XRD, and XPS. Also, the specific surface area of materials and their pore size distribution was characterized by BET. Linear sweep voltammetry curves investigated catalyst performances towards oxygen reduction and evolution reactions. Importantly, Ni1Co2-ZIFs/PAN-Ar yielded the best ORR activity, whereas Ni1Co1-ZIFs/PAN-Air exhibited the best OER performance. This work provides significant guidance for the preparation and characterization of multi-doped porous carbon nanofibers carbonized in different atmospheres.
Pengaruh Konseling Online Menggunakan Teknik Desensitisasi Sistematis Terhadap Kecemasan Siswa Pada Saat Presentasi di SMPN 232 Jakarta
Authors: Mamesah Michiko , Nur Utami Neni
Published: January 2022

Penelitian ini bertujuan untuk mengetahui pengaruh teknik Desensitisasi Sistematis untuk mengurangi tingkat kecemasan siswa pada saat presentasi di SMPN 232 Jakarta. Penelitian ini menggunakan metode penelitian subjek tunggal dengan desain A-B. Subjek dalam penelitian ini adalah seorang siswa perempuan kelas VIII SMPN 232 Jakarta yang memiliki tingkat kecemasan tinggi pada saat presentasi berdasarkan hasil pengukuran kecemasan instrumen state and trait anxiety (STAI). Data yang diperoleh selama penelitian kemudian dianalisis dengan cara analisis dalam kondisi pada kondisi baseline (A) dan kondisi intervensi (B) serta dilakukan analisis antar kondisi baseline (A) dengan kondisi intervensi (B). Skor pada kondisi baseline cenderung stabil dan skor pada kondisi intervensi cenderung menurun. Skor kecemasan sebelum dilakukan intervensi adalah 121 (berada pada kategori tinggi) kemudian menurun menjadi 64 (berada pada kategori rendah) setelah diberikan intervensi. Hasil persentase overlap pada penelitian ini memperlihatkan bahwa teknik Desensitisasi Sistematis berpengaruh pada menurunnya tingkat kecemasan siswa pada saat presentasi.
Gambaran Self-Care Guru Bimbingan dan Konseling di SMA Negeri Se-DKI Jakarta
Authors: Eka Wahyuni  , Rani Desinta
Published: January 2022

Penelitian ini bertujuan untuk mendapatkan gambaran self-care guru Bimbingan dan Konseling di SMA Negeri se-DKI Jakarta. Sampel penelitian ini berjumlah 195 guru BK dengan menggunakan teknik convenience sampling. Metode yang digunakan adalah pendekatan kuantitatif dengan metode survey. Pengumpulan data dilakukan secara online dengan menggunakan instrumen Professional Self-Care Scale.  Hasil penelitian menunjukan pada umumnya self-care guru BK di SMA Negeri se-DKI Jakarta berada pada kategori tinggi dengan rerata sebesar 123.14. Sebanyak 184 guru BK (94.36%) memiliki self-care tinggi, terdapat 11 guru BK (5.64%)  memiliki self-care sedang, dan tidak ada satupun guru BK yang memiliki self-care rendah. Pengembangan profesional mendapat rerata paling tinggi sebesar 6.20, sedangkan keseimbangan harian mendapat rerata terendah dengan skor 5.10. Strategi kognitif mendapati rerata sebesar 6.10, dukungan profesional mendapat rerata sebesar 5.90, dan keseimbangan hidup mendapat rerata sebesar 5.80.  Hasil ini menunjukan bahwa guru BK mampu mencari peluang untuk pertumbuhan profesional dan keterlibatan dalam kegiatan profesional yang menyenangkan, dapat memantau stres serta reaksi di tempat kerja, mampu menumbuhkan hubungan saling mendukung dengan rekan kerja, mampu membina hubungan dan kegiatan di luar pekerjaan, namun mereka masih membutuhkan pengembangan tentang mengelola tuntutan pekerjaan serta mengelola kegiatan sehari-hari.
CARACTERIZACIÓN DE LOS MECANISMOS DE FINANCIACIÓN PARA LAS MEDIANAS EMPRESAS DEL SECTOR AGROINDUSTRIAL COLOMBIANO
Authors:   Universidad Nacional de Colombia, ZARATE JAVIER , SUAREZ NELCY
Published: January 2022

Companies to stay and even more to grow in the market need sources of financing. This article characterizes various financing mecha- nisms, both internal and external, differen- tiating the cost, the access requirements and the profile of the company to be financed, for each mechanism. The emphasis of the article is the medium-sized companies of the Colombian agricultural industry, due to its great social relevance in relation to food security, and its economic importance as seen from the contribution of the sector in GDP, exports and employment. The purpose of this article is to generate knowledge of the different financing alternatives for medium-sized entrepreneurs in the Colombian agricultural industry.
a Schema Extraction of Document-Oriented Database for Data Warehouse
Authors: Istiqamah A. Nurul , Wiharja Kemas Rahmat Saleh
Published: January 2022

The data warehouse is a very famous solution for analyzing business data from heterogeneous sources. Unfortunately, a data warehouse only can analyze structured data. Whereas, nowadays, thanks to the popularity of social media and the ease of creating data on the web, we are experiencing a flood of unstructured data. Therefore, we need an approach that can "structure" the unstructured data into structured data that can be processed by the data warehouse. To do this, we propose a schema extraction approach using Google Cloud Platform that will create a schema from unstructured data. Based on our experiment, our approach successfully produces a schema from unstructured data. To the best of our knowledge, we are the first in using Google Cloud Platform for extracting a schema. We also prove that our approach helps the database developer to understand the unstructured data better.
A intuição em ciências e matemática: uma abordagem educacional
Authors: Teófilo de Sousa Renata
Published: January 2022

A obra Intuition in Science and Mathematics: an Educational Approach, de Efrain Fischbein traz, primordialmente, uma proposta por um viés teórico que abrange o domínio da intuição. Assim, o autor busca identificar e organizar resultados experimentais relacionados à intuição, bem como revelar suas implicações no âmbito educacional da ideia, desenvolvido para a ciência e difundido em uma ampla variedade de contextos de pesquisa e educação matemática.
Hydraulic Fracture Treatment and Landing Zone Interval Optimization: An Eagle Ford Case Study
Authors: Al Mulhim Abdulrahim K. , Miskimins Jennifer L. , Tura Ali
Published: January 2022

This paper focuses on optimizing future well landing zones and their corresponding hydraulic fracture treatments in the Eagle Ford shale play. The optimum landing zone and stimulation treatment were determined by analyzing multiple landing zone options, including the lower Austin Chalk, Eagle Ford, and Pepper Shale, with several hydraulic fracturing treatment possibilities. Fracturing fluids and their volume, proppant size, and cluster spacing were investigated to determine the optimum hydraulic fracturing treatment for the subject geologic area. Ranges of 75,000 to 300,000 gallons of pure gel, pure slickwater, and hybrid fracturing fluids along with 20/40, 30/50, 40/70, and 100 mesh proppant were tested. Cluster spacing of twenty feet to eighty feet were also sensitized in this study.

A fully three-dimensional hydraulic fracture modeling software was used to develop a geological and geomechanical model of the studied area. The generated model was calibrated with available field data to ensure that the model reflects the area's geological and geomechanical characteristics. The developed model was used to create fracture results for each sensitized parameter. Production analysis was performed for all fracture models to determine the optimum landing zone and fracturing treatment implications.

The study shows that the Eagle Ford had better production than the lower Austin Chalk in the subject area. The Pepper Shale had the highest potential hydrocarbon production, around 326 Mbbl cumulative, when fractured with a pure gel treatment. The analyses showed that a hybrid treatment with 70% gel and 30% slickwater yielded the optimum production due to the treatment economics even though the highest production was obtained using the pure gel. Treating the formation with larger proppant provided better production than smaller proppant due to conductivity concerns associated with damaging mechanisms in the studied area. Since increasing the volume above 175,000 gallons caused a negligible increase in the production, 175,000 gallons of fracturing fluid per stage appeared to be the optimum fracturing fluid volume. Thirty-foot cluster spacing was the optimum spacing in the study area. Overall, the study suggests that oil production can be improved in the Eagle Ford study area through a detailed workflow development and optimization process.

The hydraulic fracture treatment and landing zone optimization workflow ensures optimum hydrocarbon extraction from the study area. The developed workflow can be applied to new unconventional plays instead of using trial and error methods.
Casing Deformation Mitigation Achieved Through Ball Activated Sliding Fracturing Sleeves – An Alternative to Plug and Perf Fracturing Operations
Authors: Gandomkar Arjang , Katz David , Gomez Ricardo , Gundersen Anders , Khan Parvez
Published: January 2022

Casing Deformation has plagued numerous unconventional basins globally, in particular with plug-and-perforation (also known as plug-and-perf) operations. This infamous issue can greatly influence 20-30% of field productivity of horizontal wells in shale and tight oil fields (Jacobs, 2020). When a wellbore lies in a target zone and intersects many natural fractures, these fractures are perturbed by hydraulic stimulation. Therefore, rock or bedding slippage may occur, resulting in casing deformation. This phenomenon is escalated by active tectonics, high anisotropic in-situ stresses, and poor cement design.

This paper evaluates the mechanisms of casing deformation. It reviews how these conditions can be evaluated in the target zone. The mitigation procedures to reduce casing deformation through either well planning or completions design are discussed. Finally, an alternative completion method to plug-and-perf allowing limited entry completion technique in restricted casing with a field case study will be discussed.
Revision of Pressure Transient Analysis in Mature Condensate-Rich Tight Gas Fields in Sultanate of Oman
Authors: Hegazy Ahmed Elsayed , Rashdi Mohammed
Published: January 2022

Pressure transient analysis (PTA) has been used as one of the important reservoir surveillance tools for tight condensate-rich gas fields in Sultanate of Oman. The main objectives of PTA in those fields were to define the dynamic permeability of such tight formations, to define actual total Skin factors for such heavily fractured wells, and to assess impairment due to condensate banking around wellbores. After long production, more objectives became also necessary like assessing impairment due to poor clean-up of fractures placed in depleted layers, assessing newly proposed Massive fracturing strategy, assessing well-design and fracture strategies of newly drilled Horizontal wells, targeting the un-depleted tight layers, and impairment due to halite scaling. Therefore, the main objective of this paper is to address all the above complications to improve well and reservoir modeling for better development planning.

In order to realize most of the above objectives, about 21 PTA acquisitions have been done in one of the mature gas fields in Oman, developed by more than 200 fractured wells, and on production for 25 years. In this study, an extensive PTA revision was done to address main issues of this field. Most of the actual fracture dynamic parameters (i.e. frac half-length, frac width, frac conductivity, etc.) have been estimated and compared with designed parameters. In addition, overall wells fracturing responses have been defined, categorized into strong and weak frac performances, proposing suitable interpretation and modeling workflow for each case.

In this study, more reasonable permeability values have been estimated for individual layers, improving the dynamic modeling significantly. In addition, it is found that late hook-up of fractured wells leads to very poor fractures clean out in pressure-depleted layers, causing the weak frac performance. In addition, the actual frac parameters (i.e. frac-half-length) found to be much lower than designed/expected before implementation. This helped to improve well and fracturing design and implementation for next vertical and horizontal wells, improving their performances. All the observed PTA responses (fracturing, condensate-banking, Halite-scaling, wells interference) have been matched and proved using sophisticated single and sector numerical simulation models, which have been incorporated into full-field models, causing significant improvements in field production forecasts and field development planning (FDP).
Fracture Geometry Calibration Using Multiple Surveillance Techniques
Authors: Jaboob Musallam , Al Shueili Ahmed , Al Salmi Hussien , Al Hajri Salim , Merletti German , Kayumov Rifat , dwi Kurniadi Stevanus , Sebastian Trejo Ricardo
Published: January 2022

An accurate Mechanical Earth Model (MEM) is of vital importance in tight gas reservoirs where hydraulic fracturing is the only way to produce hydrocarbons economically. The Barik tight gas reservoir is the main target in Khazzan and Ghazeer Fields at the Sultanate of Oman (Rylance et al., 2011). This reservoir consists of multiple low-permeability sandstone layers interbedded with marine shales. A good understanding of the fracture propagation in such a reservoir has a major effect on completion and fracturing design. The MEM derived from sonic logs and calibrated with core data needs to be further validated by independent measurements of the fracturing geometry.

Multiple surveillance techniques have been implemented in the Barik reservoir to validate the MEM and to match observations from hydraulic fracturing operations. These techniques include closure interpretation using a wireline deployed formation testing assembly, the use of mini-frac injection tests with deployed bottomhole pressure gauges, execution of post injection time-lapse temperature logging, the injection of radioactive tracers, associated production logging, subsequent pressure transient analysis and other techniques.

A cross-disciplinary team worked with multiple sources of data to calibrate the MEM with the purpose of delivering a high-confidence prediction of the created fracture geometry, which honors all available surveillance data. In turn, this validation approach provided a solid basis for optimization of the completion and fracturing design, in order to optimally exploit this challenging reservoir and maximize the economic returns being delivered. For example, combination of stress testing with radioactive tracers provided confidence in stress barriers in this multilayered reservoir. Pressure transient analysis allowed to calibrate mechanical model to match fracturing half-length that is contributing to production.

This paper provides extensive surveillance examples and workflows for data analysis. Surveillance of this degree in the same well is uncommon because of the associated time and cost. However, it provides unique value for understanding the target reservoir. This paper demonstrates the Value Of Information (VOI) that can be associated with such surveillance and provides a concrete and practical example that can be used for the justification of future surveillance programs associated with the hydraulic fracturing operations.
Surfactant and Friction Reducer Interaction in High Salinity Slickwater Fracturing
Authors: Kotb Abdelrahman , Almubarak Tariq , Nasr-El-Din Hisham A.
Published: January 2022

Slickwater fracturing has been phenomenally successful in unconventional shale formations due to their unique geomechanical properties. Nevertheless, these treatments consume large volumes of water. On average, hydraulic fracturing treatments use up to 13,000,000 gallons of water in unconventional wells. In an effort to reduce the use of freshwater, research has focused on developing friction reducers (FR) that can be used in high salinity brines such as seawater and produced water. However, commonly used friction reducers precipitate in high salinity brine, lose their friction reduction properties, and cause severe formation damage to the proppant pack. Consequently, this work proposes the use of common surfactants to aid the FR system and achieve salt tolerance at water salinity up to 230,000 ppm. This paper will (a) evaluate five surfactants for use in high salinity FR systems, (b) evaluate the rheological properties of these systems, and (c) evaluate the damage generated from using these systems.

Four types of tests were conducted to analyze the performance of the new FR at high salinity brine. These are (a) rheology, (b) static proppant settling, (c) breakability, and (d) coreflood tests. Surfactants with ethylene oxide chain lengths ranging from 6 to 12 were incorporated in the tests. Rheology tests were done at temperatures up to 150°F to evaluate the FR at shear rates between 40-1000 s-1. Proppant settling tests were performed to investigate the proppant carrying capacity of the new FR system. Breakability and coreflood tests were conducted to study the potential damage caused by the proposed systems.

Rheology tests showed that using surfactants with high ethylene oxide chain length (>8) improved the performance of the FR at water salinity up to 230,000 ppm. Anionic surfactants performed better than cationic surfactants in improving FR performance. The ammonium persulfate was used as a breaker and showed effectiveness with the proposed formula. Finally, the retained permeability after 12 hours of injecting the FR was over 95%. This shows that after using this system, the productivity of the formation is minimally affected by the new FR system.

This research provides the first guide on studying the impact of using different ethylene oxide chain lengths of surfactants in developing new FR systems that can perform well in a high salinity environment. Given the economic and environmental benefits of reusing produced water, this new system can save costs that were previously spent on water treatments.
The Impact of Extended-Time Proppant Conductivity Impairment on the Ultimate Recovery from Unconventional Horizontal Well Completions
Authors: Pearson C. Mark , Fowler Garrett
Published: January 2022

The stimulation design of hydraulically fractured wells has always pitted the engineer's capability to maximize the fracture extent (or fracture half-length within the formation) versus the conductivity of the fracture pack generated by the deposited proppant material. In essence, the area of productive reservoir rock contacted by the hydraulic fracture treatment needs to be appropriately engineered to remain connected to the wellbore over the life of the well to maximize reservoir recovery.

The completion design of multi-stage hydraulically fractured horizontal wells has been driven by their application to unconventional oil and gas reservoirs. This has primarily occurred in North America where most of the wells drilled and completed were operated by small, private, or upstream-only independent public companies. Metrics used to evaluate performance and completion design changes were short-term in nature and typically focused on parameters such as peak-month production, 90- or 180-day cumulative production; or at longest, the first year or two of cumulative production. Capital efficiency, and capital return or well payout were drivers of value creation in an environment where the well inventory was viewed as extensive if not unlimited and the quick recycling of invested capital created the illusion of value creation.

Short-term performance metrics give credence to fracture designs that value most the early-time production that is dominated by rate acceleration. The work presented in this paper shows a comparison of fracture designs in deep unconventional formations looking to minimize cost by pumping all sand proppants versus a focus on ultimate recovery from the reservoir with designs that are more applicable to the stress regime. The work shows the importance of maintaining the wellbore connectivity to the reservoir by designing fracture treatments using proppant conductivity decline data measured over an extended-time period of months or years to maximize ultimate recovery from the reservoir. This approach will be critical to those E&P companies who view their well inventory or resource base as finite and consequently place a priority on maximizing recovery from the reservoir.
The Use of Hydraulic Completion Snubbing Units HCU in Long Laterals in U.S. Shale Plays
Authors: Frantz Joseph H. , Tourigny Matthew L.
Published: January 2022

Coiled tubing units (CTU) have been used to drill-out frac plugs in shorter horizontal shale wells for the last decade, but coil has mechanical limitations. The new innovative technology of Hydraulic Completion Snubbing Units (HCU) is gaining popularity across North and South America to drill-out frac plugs in long lateral, high-pressure, and multi-well pads. The HCU is designed for drill-outs and interventions where coil may not be the best option. This paper will summarize the recent evolution of the HCU system. Case histories will be provided from the Appalachian and Permian shale plays.

The latest HCU consists of a stand-alone unit that mounts on the wellhead after completion. The primary components include the jack assembly, a gin pole, traveling/stationary slips, a redundant series of primary/secondary blowout preventers, a rotary table, power tongs, and an equalize/bleed off loop. Tubing up to 5 ½" is used to carry a downhole motor, dual back pressure values, and the drill bit. Slickwater is used for the drilling fluid to carry out parts from the frac plugs while the tubing is rotated via the jack rotary table. Torque and drag modeling are performed to guide downhole expectations that allow most wells to be drilled in one trip and with one bit without short trips back to the heel or bottom- hole vibration assembly tools. Finally, a remote telemetry data acquisition system has been added that summarizes the drilling data and key performance indicators.

In 2016, a North American operator drilled and completed the first super lateral in the Appalachian Basin, setting the completed lateral record at over 18,500 ft. Since then, many operators have been routinely drilling laterals between 12,000 ft and 16,000 ft. HCU technology has been used in the longest laterals in onshore North America, including the lower 48 U.S records for completed lateral length (LL) at 20,800 ft and the total measured depth (MD) record at 30,677 ft. The average lateral contains between 60 to 90 plugs and can be drilled out in 3.5 to 4.5 days. The record number of plugs drilled out by an HCU is 144 and took 5.2 days. High-pressure wells are also routinely encountered where pressures range from 3000 to 8000 psi during operations. Operators are achieving faster drilling times per plug, less chemical usage, faster moves between wells, and running tubing immediately after the drill-out, thus eliminating the need for a service rig.

Operator's desire to reach total depth with the least risk and as cost-efficiently as possible resulted in the HCU gaining market acceptance. This paper will showcase the novel evolution of the HCU system that has enabled it to be a safe and effective option for interventions outside of just frac plug drill-outs such as fishing for stuck/parted coil or wireline and installing production tubing/artificial lift systems.
New insights on the theoretical study of hydrolysis mechanism of carbon disulfide (CS2) at low temperature: A density functional theory study
Authors: Wang Yue , Zhang Guijian , Shi Xin , Deng Ming , Tang Lihong , Ning Zhiyuan
Published: January 2022

Density functional theory (DFT) is used to investigate the two-step hydrolysis mechanism of CS2. By optimizing the structure of reactants, intermediates, transition states, and products, the conclusion shows that the first step of CS2 (CS2 reacts with H2O first to form COS intermediate); The second step (COS intermediate reacts with H2O to form H2S and CO2). Therefore, hydrogen migration is crucial to the mechanism of CS2 hydrolysis. In the first step of the reaction, the rate-determining step in both the single C=S path and the double C=S path has a higher barrier of 199.9 kJ/mol, but the 127.9 kJ/mol barrier in the double C=S path has a lower barrier of 142.8 kJ/mol in the single C=S path. So the double C=S path is better. Similarly, the order of the barriers for the three paths in the second reaction is C=S path < C=S path and C=O path < C=O path. So the C=S path is better. Also, to further explore the reaction of CS2 hydrolysis, the natural bond orbital (NBO) analysis of the transition states was carried out. Besides, to further explain which reaction path is better, the hydrolysis kinetics of CS2 was analyzed. It was found that the hydrolysis of CS2 was an exothermic reaction, and the increase in temperature was unfavorable to the reaction. During the hydrolysis of CS2, the six reaction paths are parallel and competitive. The results will provide a new way to study the catalytic hydrolysis of CS2.
Temporal Difference-based Graph Transformer Networks for Air Quality PM2.5 Prediction: A Case Study in China
Authors: Zhang Zhen , Zhang Shiqing , Zhao Xiaoming , Chen Linjian , Yao Jun
Published: January 2022

The acceleration of industrialization and urbanization has recently brought about serious air pollution problems, which threaten human health and lives, the environmental safety, and sustainable social development. Air quality prediction is an effective approach for providing early warning of air pollution and supporting cleaner industrial production. However, existing approaches have suffered from a weak ability to capture long-term dependencies and complex relationships from time series PM2.5 data. To address this problem, this paper proposes a new deep learning model called temporal difference-based graph transformer networks (TDGTN) to learn long-term temporal dependencies and complex relationships from time series PM2.5 data for air quality PM2.5 prediction. The proposed TDGTN comprises of encoder and decoder layers associated with the developed graph attention mechanism. In particular, considering the similarity of different time moments and the importance of temporal difference between two adjacent moments for air quality prediction, we first construct graph-structured data from original time series PM2.5 data at different moments without explicit graph structure. Then, based on the constructed graph, we improve the self-attention mechanism with the temporal difference information, and develop a new graph attention mechanism. Finally, the developed graph attention mechanism is embedded into the encoder and decoder layers of the proposed TDGTN to learn long-term temporal dependencies and complex relationships from a graph prospective on air quality PM2.5 prediction tasks. To verify the effectiveness of the proposed method, we conduct air quality prediction experiments on two real-world datasets in China, such as Beijing PM2.5 dataset ranging from 01/01/2010 to 12/31/2014 and Taizhou PM2.5 dataset ranging from 01/01/2017 to 12/31/2019. Compared with other air quality forecasting methods, such as autoregressive moving average (ARMA), support vector regression (SVR), convolutional neural network (CNN), long short-term memory (LSTM), the original Transformer, our experiment results indicate that the proposed method achieves more accurate results on both short-term (1 hour) and long-term (6, 12, 24, 48 hours) air quality prediction tasks.
Combined Effect of Telomere Length and Mitochondrial DNA Copy Number As a Potential Biomarker Indicating PE Risk: a Case-Control Study in a Chinese Population
Authors: Zhang Ruyi , Du Jiangbo , Xiao Zhendong , Jiang Yuan , Weng Qiao , Jin Liang
Published: January 2022

Purpose To explore changes of Telomere length (TL) and mitochondrial copy number (mtDNA-CN) in preeclampsia (PE) and to evaluatethe combined effect of maternal TL and mtDNA-CN on PE risk.Methods A case-control study of 471 subjects (130 PE cases and 341 age frequency matched controls) was conducted in Nanjing Drum Tower Hospital, Jiangsu Province of China. Relative telomere length (RTL) and mtDNA-CN were measured using quantitative polymerase chain reaction (qPCR) and PE risk was calculated between groups by logistic regression analyses.Results PE patients displayed longer RTL (0.48 versus 0.30) and higher mtDNA-CN (3.02 versus 2.00) in maternal bloodas well as longer cord blood RTL(0.61 versus 0.35) but lower mtDNA-CN (1.69 versus 5.49) in cord blood (all p<0.001). Exercise during pregnancy exerted an obvious effect of prolonging maternal telomere length. Multiparous, women with folic acid intake during early pregnancy and those delivered vaginally showed longer telomere length while those factors imposed no or opposite effect on RTL in PE cases. Furthermore, RTL and mtDNA-CN were positively correlated in controls (in maternal blood r=0.18, p<0.01; in cord blood r=0.19, p<0.001), but this correlation was disrupted in PE cases, no matter in maternal blood or in cord blood. Longer maternal RTL and higher mtDNA-CN were associated with higher risk of PE, and the ROC curve of RTL and mtDNA-CN in predicting PE risk presented an AUC of 0.755(95%CI: 0.698-0.812).Conclusions Interaction of TL and mtDNA-CN may play an important role in pathogenesis of PE and it could be a potential biomarker indicating PE risk.
Comparative Proteome Analysis of the Penultimate Internodes of Barley Genotypes Differing in Stem Reserve Remobilization Under Drought Stress
Authors: Hajibarat Zohreh , Saidi Abbas , Shahbazi Maryam , Zeinalabedini Mehrshad , Gorji Ahmad Mosuapour , Mirzaei Mehdi , Salekdeh Ghasem Hosseini , Ghaffari Mohammad Reza
Published: January 2022

Barley yield relies more on stem reserves under stress conditions at the grain filling stage. At terminal drought stresses, the remobilization of reserved assimilates from stem to seed contributes a major role in yield. To understand the molecular mechanism of stem reserve utilization during drought stress, a comparative proteome and physiological analyses were performed on the penultimate internodes of three genotypes of barley Yousef (tolerant), Morocco (susceptible), and PBYT17 (semi-tolerant) under drought stress at 21 and 28 days after anthesis (DAA). Under water stress and well-watered conditions Yousef showed significantly higher RWC, grain yield, and stem reserve remobilization capacity than susceptible and semi-tolerant genotypes. The proteome analysis led to the identification of 1580 differentially abundant proteins (DAPs), of which 759 and 821 proteins were differentially expressed at 21 and 28 DAA, respectively. Tolerant genotype in response to drought stress increased the abundance of several plant cell wall polysaccharide degradation proteins and protein kinases associated with posttranslational-associated, which might accelerate remobilization process for seed biomass formation compared to susceptible one under drought stress. However, the susceptible genotype increased the abundance of proteins involved in RNA metabolism and transcriptional changes to save energy sources for the growth and survival during drought stress. These findings suggest that barley might response to water stress by efficiently remobilize assimilates from stem to grain through specific remobilization processes.
Object Relocation Visual Tracking Based On Histogram Filter And Siamese Network
Authors: Zhang Jianlong , Li Qiao , Wang Bin , Chen Chen , Wang Tianhong , Zhou Yang , Li Ji
Published: January 2022

Siamese network based trackers formulate the visual tracking mission as an image matching process by regression and classification branches, which simplifies the network structure and improves tracking accuracy. However, there remain many problems as described below. 1) The lightweight neural networks decreases feature representation ability. The tracker is easy to fail under the disturbing distractors (e.g., deformation and similar objects) or large changes in viewing angle. 2) The tracker cannot adapt to variations of the object. 3) The tracker cannot reposition the object that has failed to track. To address these issues, we first propose a novel match filter arbiter based on the Euclidean distance histogram between the centers of multiple candidate objects to automatically determine whether the tracker fails. Secondly, Hopcroft-Karp algorithm is introduced to select the winners from the dynamic template set through the backtracking process, and object relocation is achieved by comparing the Gradient Magnitude Similarity Deviation between the template and the winners. The experiments show that our method obtains better performance on several tracking benchmarks, i.e., OTB100, VOT2018, GOT-10k and LaSOT, compared with state-of-the-art methods.
Probiotics Composition Harbors Against Osteoarthritis and Inflammation through GABA in Mice
Authors: Amin Uzma , Jiang Rong , Raza Shahid Masood , Liang Li , Feng Naibo , Yang Yuyou , Guo Fengjin
Published: January 2022

Background: Osteoarthritis (OA) is an age-related disease with multifactorial etiology and its prevalence growing globally. The role of Gut microbiota is inevitable concerning musculoskeletal disease and health. A method of controlling inflammation and cartilage destruction through changes in gut microbiota is proposed. Previously reported data lack the specific approach to microbial clusters and biomarkers in understanding the interactions between host and microbiome.Method: We adopted a novel approach to elaborate the positive influence of S. thermophilus and L. pentosus to treat Anterior cruciate ligament transection (ACLT) induced OA in vivo. For in vitro analysis Human Chondrocyte Cell Line (C28/I2) was used to analyze chondrogenic effect of microbes and GABA. Tukey’s multiple-comparisons test or Two-stage linear step-up procedure of Benjamini, Krieger, and Yekutieli test were used to statistically analyze the data.Results: The gut microbiota-joint axis promoted chondrogenesis and inhibited catabolism. Selected bacteria produced GABA as postbiotic. This study is the first to represent the chondrogenic and protective effects of γ-aminobutyric acid (GABA) on human chondrocytes and cartilage tissue in mice. Oral administration of it down-regulated cartilage degradation in OA-induced mice and decreased inflammation.Conclusion: We speculated the positive results from GABA and probiotics producing GABA against OA. GABA may have functional roles in chondrocyte maturation /differentiation. This data provides a foundation for further studies to elucidate the role of GABA producing microbes and GABA in the regulation of cartilaginous cell proliferation. These findings open future horizons to understand the gut-joint axis and for the treatment of OA. Thus probiotic / GABA therapy could act as a nutraceutical modulator for OA.
Transparent Montmorillonite/cellulose Nanofibril Nanocomposite Films: the Influence of Exfoliation Degree and Interfacial Interaction
Authors: Sun Chuan , Li Guanhui , Wang Jingyu , Fang Zhiqiang , Qin Famei , Chen Kaihuang , Zhou Jie , Qiu Xueqing
Published: January 2022

To obtain high performance of nanocomposite films made of cellulose nanofibrils (CNFs) and montmorillonites (MMTs), highly ordered nanostructures and abundant interfacial interactions are of extreme importance, especially for CNF film with high MMT content. Here, we tend to unveil the influence of exfoliation degree of MMTs and their interfacial interactions with CNFs on the properties of ensuing nanocomposite films. Monolayer MMTs prefer to form highly ordered nanostructure during water evaporation induced self-assembly. The obtained nanocomposite film with 30 wt% monolayer MMTs exhibits a tensile strength of 132 MPa, a total light transmittance of 90.2% (550nm), and water vapor transmission rate (WVTR) of 41.5 g•mm/m2•day, better than the film made of original bulk MMTs and CNFs (30 MPa strength, 60% transparency, and 78.7 g•mm/m2•day WVTR). Moreover, the physical properties (153 MPa strength and 20.9 g•mm/m2•day WVTR) of nanocomposite film can be further enhanced by constructing ionic interactions between the monolayer MMT and CNF using 0.5 wt% cationic polyethylenimine (PEI). However, as the amount of PEI continues to increase, its performance will be deteriorated dramatically because of the disordered orientation of monolayer MMTs. This work could provide an insight into the fabrication of high performance MMT/CNF nanocomposite film for advanced applications.
Environmental Stability and Long-term Variability of Harpacticoid Copepod Assemblages
Authors: Azovsky A I , Chertoprud Elena S , Garlitska Lesya
Published: January 2022

Harpacticoid copepods of the Chernaya Bay (White Sea) intertidal zone were collected in 45 surveys carried out from spring to autumn over a 25-year period (1996-2020) at three sites that differed in sediment properties. There were no significant long-term trends or seasonal cycles in total abundance. Regarding the species composition, the differences between sites were the most important source of variability over the whole period while the fine-scale (within-habitat) variability was low. Epibenthic species prevailed in fine silty sand, both burrowing and epibenthic species prevailed in medium sand, and interstitial and burrowing species prevailed in coarse sand. A comparison of the data on harpacticoid assemblages from a number of geographically remote loci corroborated the generality of this pattern. In the temporal dimension, the structure of each community was stable until the early 2000s, when the proportion of epibenthic, burrowing and interstitial species changed following changes in sediment properties (increasing siltation at sandy sites and decreasing siltation at the silty site). At each site, there was an increasing long-term trend in diversity (both in total richness and in expected species number). This increase was particularly apparent at sandy sites because of the appearance of epibenthic species. We suggest that sediment composition is the key factor determining the composition of harpacticoid assemblages in space and time. The “ecomorphological profile”, i.e., the proportion of species with different lifestyle and morphological traits, is a useful and informative indicator for describing and typifying these assemblages.
Biosynthesis Zinc Oxide Nanoparticles Using Senna Occidentalis Leaf Extract and Evaluation of their Cytotoxic Effect on SW480 Colon Cancer Cell Line
Authors: chaudhary Nidhi , Singh Manish Pratap , Sirohi Preeti , Afzal Shadma , Singh Nand K.
Published: January 2022

ObjectiveIn the present study, we green synthesized ZnO NPs (zinc oxide nanoparticles) from Senna occidentalis leaf extract which were subsequently assessed for their cytotoxic and antioxidant activity on colon cancer SW480 cell line.Results Zinc oxide nanoparticles were characterized by using UV-Vis spectroscopy, X-ray diffractometer (XRD), Particle size analyzer (PSA), Fourier transform infrared spectroscopy (FTIR), Field emission scanning electron microscopy (FE-SEM), Energy-dispersive X-ray (EDS) and atomic force microscope (AFM) analysis. The PSA, XRD and AFM showed 20-50 nm size and nearly cuboidal and irregular shaped of the ZnO NPs. The synthesized ZnO nanoparticles were evaluated for their anticancer activity on human colon cancer cell line (SW480) by using MTT and neutral red uptake assay. The SW480 colon cancer cells were treated with various concentrations of ZnO NPs in the range of 20–100 µg/ml for 2 hrs. The result showed that ZnO NPs could reduce cell viability of SW480 cells up to 50% at the concentration of 100 µg/ml and induce membrane leakage in a concentration dependent manner.ConclusionThe anticancer activity of zinc oxide nanoparticles has showed that these can be used as effective anti-cancer agent against colon cancer cell lines (SW480).
Anomalous Arctic Sea Ice Melting Linked to Recent Warming Amplification
Authors: Yadav Juhi , Kumar Avinash , Mohan Rahul , Ravichandran Muthulagu
Published: January 2022

This study investigates the mechanism of seasonal sea ice variation and recent warming amplification. Seasonal temperature changes in the vertical structure reveal that the autumn and winter seasons are warming more than summer. The thermodynamic processes of sea-ice-air interactions via the heat flux component have been studied. The summer Arctic Sea ice has receded by half (∼52%), producing excessive heat. This sea ice loss plays a significant role in determining the heat exchange between the ocean and atmosphere in the following season. During a warm season, the ocean heats up due to incident solar radiation. As a result, delayed ice growth and atmospheric warming occur. Sea ice and heat flux feedbacks explain a large part of Arctic atmospheric warming. These abrupt changes are closely coupled to accelerated Arctic Sea ice loss and atmospheric warming, which are still uncertain.
Doppler Mitral Inflow Variables Time Course After Treadmill Stress Echo with and Without Ischemic Response
Authors: LULIĆ FABIJAN , VIRAG ZDRAVKO
Published: January 2022

This study evaluated Doppler mitral inflow variables changes from rest to post-exercise among 104 subjects with and without echocardiographic evidence of ischemic response (IR) to exercise (63.9 ± 11 years, 54% male, 32% with IR) who underwent a clinically indicated treadmill stress echo (TSE) test. The time from exercise cessation to imaging (TIME) was recorded. The changes (after TSE minus baseline values) in the peak E-wave velocity (∆E) [34.2 vs. 24.2, p = 0.024] and E-wave deceleration rate (∆DR) [348.0 vs. 225.7, p = 0.010] were bigger in ischemic than in nonischemic subjects, while the changes in the peak A-wave velocity (∆A) did not differ [7.9 vs. 15.0, p = 0.082]. The correlations between Doppler variables and IR, TIME, and TIME*IR interaction were analyzed. We observed a significant interaction between TIME and IR regarding ∆E and ∆DR. The differences in the regression line slopes of time courses for ∆E and ∆DR based on IR were significant: ∆E (–0.09 vs. –8.17, p = 0.037) and ∆DR (11.23 vs. –82.60, p = 0.022). Main findings: 1. Time courses after exercise of ∆E and ∆DR in subjects with and without IR were different. 2. ∆E and ∆DR did not differ between subjects with and without IR at exercise cessation (TIME = 0). 3. The simple main effect of ischemia on ∆E and ∆DR was significant at TIME of ≥3 min. Divergent time courses of ∆E and ∆DR after exercise might be promising for detecting diastolic dysfunction caused by ischemia.
Evaluation of Central Corneal Epithelial Thickness With Anterior Segment OCT in Patients With Type 2 Diabetes Mellitus
Authors: yusufoglu elif , kobat sabiha güngör , keser sinem
Published: January 2022

Aim: The aim of this study was to evaluate the central corneal thickness (CCT) and central corneal epithelial thickness (CCET) in patients with Type 2 diabetes mellitus (DM), and the effect of the duration of diabetes, the degree of diabetic retinopathy (DR), and HbA1c level. Method: CCT and CCET values ​​of 72 patients diagnosed with type 2 DM and 72 healthy individuals were measured by anterior segment optical coherence tomography (AS-OCT). The eye tear function was evaluated with the Tear Break-up Time test (TBUT) and the Schirmer test. From the results of fundus examination, the diabetic patients were grouped as those without DR, with non-proliferative DR, and with proliferative DR. The disease duration and the HbA1c levels were recorded. Results: In the diabetic patients, the mean CCT was determined to be thicker (p=0.025), the CCET was thinner (p=0.003), and the TBUT and Schirmer values were lower (p<0.001, p<0.001, respectively). The duration of diabetes and the HbA1c level were not found to have any statistically significant effect on these parameters (p>0.05). The presence of retinopathy had no significant effect on CCT, TBUT and Schirmer values. The CCET was determined to be thinner in patients with retinopathy (p<0.001). Conclusion: As the corneal epithelial thickness is reduced in patients with advanced diabetic retinopathy, corneal epithelial pathologies can be seen more often. Therefore, early and effective treatment can be started taking into consideration the complications which may develop associated with the corneal epithelium following surgical procedures, especially those applied to the cornea.
Two Notes on the Theoretical Physics of ATP Synthase
Authors: Chaturvedi Archit
Published: January 2022

ATP Synthase is an essential molecule in cell and molecular biology. It is responsible for the production of ATP during cellular respiration, a molecule that provides the energy required to drive a number of cellular processes. In this paper, I explore the rotational physics of ATP Synthase’s rotor, a part of the protein that spins during the production of ATP. Firstly, I discuss some elementary rotational kinematics of the rotor. I then derive two alternate formulations for the total linear acceleration of the rotor. Finally, I derive formulas for the moment of inertia, angular momentum, net torque, and kinetic energy of the rotor. Through this, I hope to provide a theoretical and mathematical insight into the mechanics of ATP Synthase during the production of ATP.