bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of poly (ethylene-butene) and nano-aluminium oxide blend on the viscosity of Nigerian crude oil
Authors: Odutola Toyin Olabisi , Idemili Chinenye Anita 
Published: April 2020

AbstractWax deposition in production tubing and pipelines is very critical in Nigeria petroleum industry. It can lead to a reduction in production, shut-in of wells, choking of flow lines, failure of downhole equipment, increased power requirement and loss in revenue. In the bid to address this issue, a Niger Delta crude oil sample was characterized in this study to know its wax deposition tendency and other chemical properties. The effect of temperature on the viscosity of the crude oil sample was studied, and the degree of viscosity reduction (DVR) of the crude oil sample in the presence of poly (ethylene-butene) (PEB) and nano-aluminium oxide (Al2O3) blend at different temperatures was evaluated. 100 ppm of nano-Al2O3blend with 1000 ppm, 2000 ppm and 5000 ppm of PEB, respectively, was added to the crude oil sample at different temperatures, and the degree of viscosity reduction (DVR) in each blend at 10 °C, 15 °C, 20 °C, 30 °C and 35 °C was evaluated. The blend with 2000 ppm of PEB with 100 ppm nano-Al2O3is the best for offshore application as it gave the highest DVR of 77.9% and 73.7% at 10 °C and 15 °C, respectively, while the other blends gave a DVR of about 70% at 10 °C and 15 °C. As the crude sample temperature approached the wax appearance temperature of 29 °C, the DVR of PEB/Al2O3blend drastically reduced. PEB/Al2O3blend inhibited wax precipitation, and at low temperatures, a significant reduction in the viscosity of the crude oil sample was observed, which makes it a good recommendation for offshore application.
Preparation and Certification of a New Salvianolic Acid A Reference Material for Food and Drug Research
Authors: Yang Dezhi , Su Bin , Bi Yancai , Zhang Li , Zhang Baoxi , Song Junke , Lu Yang , Du Guanhua 
Published: April 2020

Abstract
Salvianolic acid A (Sal A), a water-soluble ingredient in Danshen, has various biological activities. Sal A and its impurities have similar physical and chemical properties, as well as strong reducibility; therefore, they are difficult to prepare and purify. In this study, high-purity Sal A was obtained by purification of sephadex chromatography and preparative chromatography. Furthermore, HPLC–DAD tandem ECD and HPLC–DAD tandem MS methods were used for non-volatile organic impurity analysis, ICP-MS method was used for non-volatile inorganic impurities and mass balance method and quantitative nuclear magnetic resonance were employed to certify the product. The structures of Sal A and its relative impurities were validated by nuclear magnetic resonance spectroscopy and mass spectrometry, and their contents were quantified as well. Following the principles of ISO Guides 34:2009 and 35:2005, a Sal A reference material was certified, covering homogeneity studies, stability studies, characterization, and uncertainty estimations.

Graphic Abstract
The effect of ethanol evaporation on the properties of inkjet produced liposomes
Authors: Bnyan Ruba , Cesarini Laura , Khan Iftikhar , Roberts Matt , Ehtezazi Touraj 
Published: April 2020

Abstract
Background
Inkjet method has been used to produce nano-sized liposomes with a uniform size distribution. However, following the production of liposomes by inkjet method, the solvent residue in the product could have a significant effect on the properties of the final liposomes.

Objective
This research paper aimed to find a suitable method to remove ethanol content and to study its effect on the properties of the final liposomal suspension.

Method
Egg phosphatidylcholine and lidocaine were dissolved in ethanol; and inkjet method at 80 kHz was applied to produce uniform droplets, which were deposited in an aqueous solution to form liposomes. Dry nitrogen gas flow, air-drying, and rotary evaporator were tested to remove the ethanol content. Liposome properties such as size, polydispersity index (PDI), and charge were screened before and after ethanol evaporation.

Results
Only rotary evaporator (at constant speed and room temperature for 2 h) removed all of the ethanol content, with a final drug entrapment efficiency (EE) of 29.44 ± 6.77%. This was higher than a conventional method. Furthermore, removing ethanol led to liposome size reduction from approximately 200 nm to less than 100 nm in most samples. Additionally, this increased the liposomal net charge, which contributed to maintain the uniform and narrow size distribution of liposomes.

Conclusion
Nano-sized liposomes were produced with a narrow PDI and higher EE compared to a conventional method by using an inkjet method. Moreover, rotary evaporator for 2 h reduced effectively the ethanol content, while maintaining the narrow size distribution.
Spintronics in Two-Dimensional Materials
Authors: Liu Yanping , Zeng Cheng , Zhong Jiahong , Ding Junnan , Wang Zhiming M. , Liu Zongwen 
Published: April 2020

AbstractSpintronics, exploiting the spin degree of electrons as the information vector, is an attractive field for implementing the beyond Complemetary metal-oxide-semiconductor (CMOS) devices. Recently, two-dimensional (2D) materials have been drawing tremendous attention in spintronics owing to their distinctive spin-dependent properties, such as the ultra-long spin relaxation time of graphene and the spin–valley locking of transition metal dichalcogenides. Moreover, the related heterostructures provide an unprecedented probability of combining the different characteristics via proximity effect, which could remedy the limitation of individual 2D materials. Hence, the proximity engineering has been growing extremely fast and has made significant achievements in the spin injection and manipulation. Nevertheless, there are still challenges toward practical application; for example, the mechanism of spin relaxation in 2D materials is unclear, and the high-efficiency spin gating is not yet achieved. In this review, we focus on 2D materials and related heterostructures to systematically summarize the progress of the spin injection, transport, manipulation, and application for information storage and processing. We also highlight the current challenges and future perspectives on the studies of spintronic devices based on 2D materials.
Identifying the Representational Structure of Affect Using fMRI
Authors: Mattek Alison M. , Burr Daisy A. , Shin Jin , Whicker Cady L. , Kim M. Justin 
Published: April 2020

AbstractThe events we experience day to day can be described in terms of their affective quality: some are rewarding, others are upsetting, and still others are inconsequential. These natural distinctions reflect an underlying representational structure used to classify affective quality. In affective psychology, many experiments model this representational structure with two dimensions, using either the dimensions of valence and arousal, or alternatively, the dimensions of positivity and negativity. Using fMRI, we show that it is optimal to use all four dimensions to examine the data. Our findings include (1) a gradient representation of valence that is anatomically organized along the fusiform gyrus and (2) distinct sub-regions within bilateral amygdala that track arousal versus negativity. Importantly, these results would have remained concealed had either of the commonly used 2-dimensional approaches been adopted a priori, demonstrating the utility of our approach.
Trends in Smart Manufacturing: Role of Humans and Industrial Robots in Smart Factories
Authors: Evjemo Linn D. , Gjerstad Tone , Grøtli Esten I. , Sziebig Gabor 
Published: April 2020

Abstract
Purpose of Review
This paper provides an overview of the role of humans and robots in smart factories, their connection to Industry 4.0, and which progress they make when it comes to related technologies.

Recent Findings
The current study shows that a decade was not enough to provide a reference implementation or application of Industry 4.0, like smart factories. In 2011, Industry 4.0 was mentioned for the first time in the scientific community. Industry 4.0 arrived with many new enabling technologies and buzzwords, e.g., Internet of Things (IoT), Cyber-Physical Systems (CPS), and Digital Twins (DT).

Summary
This paper first defines smart factories and smart manufacturing in relation to the role of humans and robots. Followed by an overview of selected technologies in smart factories. Concluded by future prospects and its’ relation to smart manufacturing.
Ionospheric Effects During the Total Solar Eclipse Over Southeast Asia‐Pacific on 9 March 2016: Part 1. Vertical Movement of Plasma Layer and Reduction in Electron Plasma Density
Authors: Dear Varuliantor , Husin Asnawi , Anggarani Sefria , Harjosuwito Jiyo , Pradipta Rezy 
Published: April 2020

AbstractWe report our investigation of ionospheric effects that occurred during a total solar eclipse over the Southeast Asia‐Pacific region on 9 March 2016. In particular, here we examine rapid uplift of the ionospheric F‐layer during the eclipse, and reductions of ionospheric plasma density in areas around the eclipse totality. This study used data from ionosondes at Biak and Guam, as well as data from a bistatic HF radio link (∼1300 km apart, cutting across the eclipse totality trajectory) between Biak and Manado. Gridded total electron content (TEC) data from the Madrigal Database were also used for a cross‐comparison. The ionosonde measurements indicate an upward vertical drift velocity in the range of 21−40 m/s in the ionospheric F‐region during the eclipse. Over Biak, foF2 decreased from 10 MHz to 6 MHz (a 40% reduction) during the eclipse. Meanwhile, foF2 over Guam during the eclipse was suppressed for a few hours; lower than the 7‐day average normal level by 3 MHz. The Madrigal GPS TEC data corroborate these ionosonde measurements. Finally, data from the Biak‐Manado HF radio link indicate that the D‐region ionosphere had diminished substantially during the eclipse.
Exploring Thermospheric Variations Triggered by Severe Geomagnetic Storm on 26 August 2018 Using GRACE Follow‐On Data
Authors: Krauss S. , Behzadpour S. , Temmer M. , Lhotka C. 
Published: April 2020

AbstractWith the successful launch of the satellite mission Gravity Recovery and Climate Experiment (GRACE) Follow‐On in May 2018 the opportunity arises to resume the analysis of accelerometer data regarding space weather induced perturbations of the Earth's thermosphere. On 21 August 2018 a complex interplanetary coronal mass ejections occurred on the Sun, which subsequently triggered an unexpected large geomagnetic storm on 26 August. We present a detailed analysis of the interplanetary coronal mass ejection eruption and explore the occurred perturbation of the neutral mass density in the upper Earth's atmosphere. Due to the heating and the subsequent expansion of the thermosphere also the drag force acting on the spacecraft is enhanced. This leads to an additional storm‐induced orbit decay, which we calculate by means of variations in the semimajor axis. The evaluation is based on the utilization of accelerometer measurements from GRACE Follow‐On. For the reduction of disturbing nongravitational forces we implemented a physical shadow function, which incorporates the Earth's oblateness and the atmospheric refraction and extinction. Additionally, the estimation of Earth's reradiation is now based on hourly measurements by the Clouds and the Earth's Radiant Energy System. The resulting atmospheric densities and orbit decays are compared with predictions from our preliminary thermospheric forecasting tool, which is based on the study by Krauss et al. (2018, https://doi.org/10.1029/2018JA025778). The evaluation shows that the maximum estimated orbit decay triggered by the geomagnetic storm on 26 August is in the order of approximately 8.2 m and thus in good accordance with the forecasted value (9.5 m)—predicted with a lead time of about 60 min.
Experimental Investigation of the Streamer Zone of Long‐Spark Positive Leader Using High‐Speed Photography and Microwave Probing
Authors: Bogatov N. A. , Kostinskiy A. Yu , Syssoev V. S. , Andreev M. G. , Bulatov M. U. , Sukharevsky D. I. , Mareev E. A. , Rakov V. A. 
Published: April 2020

AbstractThe streamer zone of positive leader during the breakthrough phase of long sparks was experimentally investigated with two methods. One of the methods is the analysis of streamer‐zone images obtained with a high‐speed framing camera with image enhancement. This method allowed us to estimate the spatial distribution of streamer density and low‐frequency conductivity in the streamer zone. The other method is the microwave probing, which we applied for the first time to long sparks. The attenuation of microwave beam in the streamer zone in our experiments is proportional to the total number of free electrons inside the microwave beam. Experimental data on the microwave attenuation combined with the streamer density found using the first method allowed us to estimate the total number of free electrons in one streamer. The following parameters were obtained. The streamer density in the center of the streamer zone is (0.6–1) · 105 m−3, and the total number of streamers in the streamer zone is 4 · 105–106. The average total number of free electrons in one streamer is about 3 · 1010. Low‐frequency conductivity on the axis of streamer zone was estimated to be typically 2 · 10−5 S/m, which is similar to that estimated for corona sheath in lightning. Both methods are based on the assumption of constancy of electric field and similarity of all streamers inside the streamer zone. The overall results of this study are generally consistent with this assumption.
Repeated Subsurface Thermal Profiling to Reveal Temporal Variability in Deep Groundwater Flow Conditions
Authors: Bense V. F. , Kurylyk B. L. , de Bruin J. G. H. , Visser P. 
Published: April 2020

AbstractReliably quantifying groundwater fluxes to and from confined aquifers in sedimentary basins is increasingly recognized as a critical challenge that impedes sustainable groundwater management. One approach to quantify such fluxes is through the analysis of deep (e.g., >50 m) borehole thermal profiles penetrating through aquifer‐aquitard systems. Recently developed methods to interpret such data exploit the relationship between vertical groundwater flow and the downward propagation of surface temperature disturbances resulting from climate warming. In this note, we advance beyond prior studies that assumed steady‐state groundwater flow by demonstrating how hydrogeological regime shifts on decadal time scales can be quantitatively inferred from temperature‐depth profiles (TDPs). We use a set of repeated temperature‐depth profiles from one site in an unconsolidated sedimentary aquifer system, recorded in 1980 and 2016/2018 to tentatively infer a minimum of a threefold increase in groundwater downwelling to deeper aquifers (i.e., from 100 to 350 mm/year). The enhanced flux likely results from intensified, deep groundwater abstraction in the vicinity since the mid‐1980s. We reach this conclusion through analyzing the occurrence and downward propagation of the minimum temperature in the profiles as well as the temporal trend in deeper groundwater temperatures. We conclude that repeated temperature‐depth profiles can be suitable to archive hydrogeological changes. Our results provide the impetus for more systematic collection of present‐day TDPs to provide a historical benchmark from which to assess future groundwater flow alterations, especially in areas that lack traditional aquifer monitoring via hydraulic head measurements.
Compiling Magnetosheath Statistical Data Sets Under Specific Solar Wind Conditions: Lessons Learnt From the Dayside Kinetic Southward IMF GEM Challenge
Authors: Dimmock A. P. , Hietala H. , Zou Y. 
Published: April 2020

AbstractThe Geospace Environmental Modelling (GEM) community offers a framework for collaborations between modelers, observers, and theoreticians in the form of regular challenges. In many cases, these challenges involve model‐data comparisons to provide wider context to observations or validate model results. To perform meaningful comparisons, a statistical approach is often adopted, which requires the extraction of a large number of measurements from a specific region. However, in complex regions such as the magnetosheath, compiling these data can be difficult. Here, we provide the statistical context of compiling statistical data for the southward IMF GEM challenge initiated by the “Dayside Kinetic Processes in Global Solar Wind‐Magnetosphere Interaction” focus group. It is shown that matching very specific upstream conditions can severely impact the statistical data if limits are imposed on several solar wind parameters. We suggest that future studies that wish to compare simulations and/or single events to statistical data should carefully consider at an early stage the availability of data in context with the upstream criteria. We also demonstrate the importance of how specific IMF conditions are defined, the chosen spacecraft, the region of interest, and how regions are identified automatically. The lessons learnt in this study are of wide context to many future studies as well as GEM challenges. The results also highlight the issue where a global statistical perspective has to be balanced with its relevance to more‐extreme, less‐frequent individual events, which is typically the case in the field of space weather.
Revising the Ozone Depletion Potentials Metric for Short‐Lived Chemicals Such as CF3I and CH3I
Authors: Zhang Jun , Wuebbles Donald J. , Kinnison Douglas E. , Saiz‐Lopez Alfonso 
Published: April 2020

AbstractOzone depletion potentials (ODPs) are an important metric in national and international policy for evaluating the relative importance of different gases to affecting stratospheric ozone. In evaluating the ODPs of iodotrifluoromethane (CF3I) and methyl iodide (CH3I) using the recently updated understanding of atmospheric iodine chemistry, only minor ozone loss would be expected to occur in the stratosphere from the very short‐lived (~6 days) CF3I, with slightly larger destruction of stratospheric ozone from CH3I (~12 days). In addition, most of the ozone destruction would likely occur in the lower troposphere over continental surfaces, reducing anthropogenic ozone pollution. The traditional ODP concept uses total column ozone change, but this is not an accurate representation of potential future use of very short‐lived substances (VSLSs) on the abundance of stratospheric ozone. A new metric, Stratospheric ODP (or SODP), is defined that only accounts for stratospheric ozone loss, providing a useful additional tool for policy considerations of VSLSs on stratospheric ozone.
Associations between different dimensions of prenatal distress, neonatal hippocampal connectivity, and infant memory
Authors: Scheinost Dustin , Spann Marisa N. , McDonough Laraine , Peterson Bradley S. , Monk Catherine 
Published: April 2020

AbstractPrenatal maternal distress—an umbrella concept encompassing multiple negative psychological states including stress, anxiety, and depression—is a substantial prenatal exposure. Consistent across preclinical and human studies, the hippocampus displays alterations due to prenatal distress. Nevertheless, most prenatal distress studies do not focus on multiple dimensions of, have not examined hippocampal functional connectivity in association with, and do not consider observer-based functional outcomes related to distress. We investigated the effects of different dimensions of prenatal distress in pregnant adolescents, a population at high risk for distress, in association with neonatal hippocampal connectivity and infant memory. In pregnant adolescents (n = 42), we collected four measures of distress (perceived stress, depression, pregnancy-specific distress, and 24-h ambulatory salivary cortisol) during the 2nd and 3rd trimesters. Resting-state imaging data were acquired in their infants at 40–44 weeks post-menstrual age. Functional connectivity was measured from hippocampal seeds. Memory abilities were obtained at 4 months using the mobile conjugate reinforcement task. Shared across different dimensions of maternal distress, increased 3rd trimester maternal distress associated with weaker hippocampal–cingulate cortex connectivity and stronger hippocampal–temporal lobe connectivity. Perceived stress inversely correlated while hippocampal–cingulate cortex connectivity positively correlated with infant memory. Increased cortisol—collected during the 2nd, but not the 3rd, trimester—associated with weaker hippocampal–cingulate cortex connectivity and stronger hippocampal–temporal lobe connectivity. Different dimensions of prenatal maternal distress likely contribute shared and unique effects to shaping infant brain and behavior.
A key ‘foxy’ aroma gene is regulated by homology-induced promoter indels in the iconic juice grape ‘Concord’
Authors: Yang Yingzhen , Cuenca José , Wang Nian , Liang Zhenchang , Sun Honghe , Gutierrez Benjamin , Xi Xiaojun , Arro Jie , Wang Yi , Fan Peige , Londo Jason , Cousins Peter , Li Shaohua , Fei Zhangjun , Zhong Gan-Yuan 
Published: April 2020

Abstract‘Concord’, the most well-known juice grape with a parentage of the North American grape speciesVitis labruscaL., possesses a special ‘foxy’ aroma predominantly resulted from the accumulation of methyl anthranilate (MA) in berries. This aroma, however, is often perceived as an undesirable attribute by wine consumers and rarely noticeable in the common table and wine grape speciesV. vinifera. Here we discovered homology-induced promoter indels as a major genetic mechanism for species-specific regulation of a key ‘foxy’ aroma gene, anthraniloyl-CoA:methanol acyltransferase (AMAT), that is responsible for MA biosynthesis. We found the absence of a 426-bp and/or a 42-bp sequence inAMATpromoters highly associated with high levels ofAMATexpression and MA accumulation in ‘Concord’ and otherV. labrusca-derived grapes. These promoter variants, all with direct and inverted repeats, were further confirmed in more than 1,300Vitisgermplasm. Moreover, functional impact of these indels was validated in transgenicArabidopsis. Superimposed on the promoter regulation, large structural changes including exonic insertion of a retrotransposon were present at theAMATlocus in someV. viniferagrapes. Elucidation of theAMATgenetic regulation advances our understanding of the ‘foxy’ aroma trait and makes it genetically trackable and amenable in grapevine breeding.
One‐third optical frequency divider for dual‐wavelength optical signals based on an optoelectronic oscillator
Authors: Liu Hongfei , Zhu Nan , Liu Shifeng , Zhu Dan , Pan Shilong 
Published: April 2020

An optical frequency divider for dual‐wavelength optical signals based on an optoelectronic oscillator (OEO) is proposed and experimentally demonstrated. The Mach–Zehnder modulator in the OEO is biased at the minimum transmission point, the OEO‐based frequency divided signal originates from system noise. When the oscillation phase and amplitude conditions met, it gets stabilised at an oscillation frequency which is one‐third of the frequency interval of the injected dual‐wavelength optical signal. A proof‐of‐concept experiment is verified. With the frequency interval of the dual‐wavelength optical signal ranging from 101.4 to 120.6 GHz, the RF signals ranging from 33.8 to 40.2 GHz are successfully generated. The power ripple is lower than 2.92 dB and the rejection ratio of the harmonic components is larger than 39 dB for all the conditions. The phase noise values of the generated RF signals are kept to be around −105 dBc/Hz@10 kHz.