bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modified Archie’s parameters for estimating water saturation for carbonate reservoir in north of Iraq
Authors: Jumaah Hayder A. 
Published: August 2021

AbstractArchie’s parameters, cementation factor (m), saturation exponent (n) and tortuosity factor (a), are general factor that have effects on water saturation magnitude, due to their sensitivity to pores distribution, lithofacies properties and wettability, particularly in carbonate reservoirs. Water saturation magnitude has a direct effect in estimating initial oil-in-place values, and inaccuracy in its values will lead to huge impact errors in initial oil-in-place values, so it would affect the economics of field management and development plans. In this paper, the main objective was to investigate the impact of using conventional and modified Archie’s parameters in the determination of water saturation from well log interpretation for Tertiary reservoir in Khabaz oil field, a heterogenous carbonite reservoir in the north of Iraq which was affected by different digenesis processes that impacted the reservoir quality. Tertiary reservoir of Khabaz field consists of five geological units (A, B, C, D and E), and the selected well penetrated the top of the reservoir at 2200.5 m RTKB and passed through five geological units and reached total depth at 2348 m RTKB. The geothermal gradient of the field was 1.12 ℉ per 100 ft, and formation water resistivity (Rw) was about 0.029 Ω m. Water saturation was at first estimated from resistivity logs by Archie model with conventional known values of parameters (a,mandn) (1, 2 and 2), respectively, and then Archie’s parameters were modified and determined by graphical technique of Pickett plot for each geological unit to estimate water saturation. Finally, the results show the water saturation value was more sensitive for Archie’s parameter in low-porosity and high-clay-volume zone, but less sensitive in clean high-porosity zone, and water saturation values determined by modified Archie model were less about 18.5% at mean than their value by using conventional Archie’s parameters.
Consciousness: Just Another Technique?
Authors: Barthelmeß Ulrike , Furbach Ulrich 
Published: August 2021

AbstractThis note is intended as a contribution to the discussion whether artificial systems can have consciousness. Based on the notion of Tononi’s Information Integration Theory we will argue, that AI systems that have to reason with large knowledge bases need such techniques in order to handle them efficiently. We furthermore discuss mind-wandering and creativity on this basis.
Tumor suppressive effect of scavenger receptor class A member 5 overexpression in colorectal cancer by regulating PI3K/AKT/mTOR pathway
Authors: Li Yi , Peng Feng , Tan Xiangyun , Wang Jin , Xu Yeqing 
Published: August 2021

Abstract
Background
Colorectal cancer (CRC) exhibits high risks of morbidity and mortality.

Objective
To investigate the effect of scavenger receptor class A member 5 (SCRAR5) on CRC and its mechanism on modulation of cancer development.

Methods
The SCRAR5 expression in four kinds of CRC cell lines (SW620, SW480, HT29, and HCT116) was measured by quantitative PCR and western blotting, respectively. The effects of SCRAR5 abnormal expression on cell proliferation, apoptosis, and migration were analyzed by CCK-8 assay, EdU assay, colony-forming assay, flow cytometry assay, Transwell assay and wound healing assay, respectively. Meanwhile, the involvements of PI3K/AKT/mTOR pathway with the role of SCRAR5 were investigated by western blotting. Afterwards, the in vivo effects of SCRAR5 abnormal expression on CRC xenograft mice were finally investigated by evaluating tumor volume, apoptosis and Ki67 expression.

Results
SCRAR5 was lowly expressed in CRC cell lines, especially SW480 cells. Up-regulation of SCRAR5 significantly promoted cell apoptosis, reduced cell proliferation and migration in SW480 cells. Notably, SCRAR5 overexpression obviously inhibited the phosphorylation levels of PI3K, AKT, and mTOR. Reversely, SCRAR5 silence exhibited promoting effects on HT29 cells. Consistently, in vivo experiments also revealed that SCRAR5 overexpression remarkably suppressed tumor volume and Ki67 expression, as well as promoted cell apoptosis.

Conclusions
Overall, up-regulating of SCRAR5 obviously inhibited CRC tumor growth in vitro and in vivo, which might be related to PI3K/AKT/mTOR pathway.
The potential of full-electric aircraft for civil transportation: from the Breguet range equation to operational aspects
Authors: Staack Ingo , Sobron Alejandro , Krus Petter 
Published: August 2021

AbstractThe decades-old idea of electric-powered commercial flight has re-emerged alongside high expectations for greener CO2 emission-free air transportation. But to what extent can electric aircraft reduce the energy and environmental footprint of aviation? What should such aircraft look like, and how does their operation compare to conventional jet aircraft? What technologies are needed and which of them are already in place? This paper goes back to the basics of flight physics and critically analyzes some of the unresolved challenges that lay ahead. Current commercial operations are examined and the short-term effects of any electrification of short-range flights are quantified. Fundamental system components and basic design and operating concepts are analysed to highlight unavoidable constraints that often seem to be misunderstood or overlooked. These limitations are illustrated with a conceptual study of a full-electric FAR/CS-23 commuter aircraft and realistic estimations of its performance. It becomes clear that electric propulsion alone will not fully meet society’s expectations, even if key enabling technologies continue to develop as forecast. Nevertheless, this paper suggests that electrification may instead become one piece of a propulsion-technology mix that would more effectively address our short- and long-term emission goals.
Review of flight simulation fidelity requirements to help reduce ‘rotorcraft loss of control in-flight’ accident rates
Authors: White Mark D. , Padfield Gareth D. , Lu Linghai , Advani Sunjoo , Potter Mario 
Published: August 2021

AbstractThis paper examines the fidelity requirements for flight simulators to improve training and address the problems associated with rotorcraft loss of control in-flight (LOC-I). To set the context, trends in rotorcraft accident statistics are presented. The data show that, despite recent safety initiatives, LOC-I rotorcraft accidents have been identified as a significant and growing contribution to accident rates. In the late 1990s, the fixed-wing commercial aircraft community faced a similar situation relating to upset prevention and recovery, and through a coordinated international effort, developed a focussed training programme to reduce accident rates. Lessons learned from the fixed-wing programme are presented to highlight how improved rotorcraft modelling and simulation tools are required to reduce rotorcraft accidents through higher quality, simulator-based training programmes. Relevant flight simulator certification standards are reviewed, with an emphasis on flight-model fidelity and vestibular motion cueing requirements. The findings from rotorcraft modelling and motion cueing research, that highlight relevant fidelity issues, are presented to identify areas for further activities to enhance the fidelity of simulators standards for use in LOC-I prevention training.
Echo chamber detection and analysis
Authors: Villa Giacomo , Pasi Gabriella , Viviani Marco 
Published: August 2021

AbstractSocial media allow to fulfill perceived social needs such as connecting with friends or other individuals with similar interests into virtual communities; they have also become essential as news sources, microblogging platforms, in particular, in a variety of contexts including that of health. However, due to the homophily property and selective exposure to information, social media have the tendency to create distinct groups of individuals whose ideas are highly polarized around certain topics. In these groups, a.k.a. echo chambers, people only "hear their own voice,” and divergent visions are no longer taken into account. This article focuses on the study of the echo chamber phenomenon in the context of the COVID-19 pandemic, by considering both the relationships connecting individuals and semantic aspects related to the content they share over Twitter. To this aim, we propose an approach based on the application of a community detection strategy to distinct topology- and content-aware representations of the COVID-19 conversation graph. Then, we assess and analyze the controversy and homogeneity among the different polarized groups obtained. The evaluations of the approach are carried out on a dataset of tweets related to COVID-19 collected between January and March 2020.
Swelling-Based Chemical Sensing With Unmodified Optical Fibers
Authors: Jderu Alin , Dorobantu Dorel , Ziegler Dominik , Enachescu Marius 
Published: August 2021

AbstractWe use distributed fiber optic strain sensing to examine swelling of the fiber’s polymer coating. The distributed sensing technique that uses unmodified low-cost telecom fibers opens a new dimension of applications that include leak detection, monitoring of water quality, and waste systems. On a short-range length scale, the technology enables “lab-on-a-fiber” applications for food processing, medicine, and biosensing for instance. The chemical sensing is realized with unmodified low-cost telecom optical fibers, namely, by using swelling in the coating material of the fiber to detect specific chemicals. Although generic and able to work in various areas such as environmental monitoring, food analysis, agriculture or security, the proposed chemical sensors can be targeted for water quality monitoring, or medical diagnostics where they present the most groundbreaking nature. Moreover, the technique is without restrictions applicable to longer range installations.
Pediatric Medical Traumatic Stress (PMTS) following Surgery in Childhood and Adolescence: a Systematic Review
Authors: Stanzel Anna , Sierau Susan 
Published: August 2021

AbstractThe purpose of the present review was to systematically review, synthesize and quantify prevalence rates of subclinical and clinical psychological symptoms in children and adolescents who have undergone surgery. Systematic literature searches were conducted twofold in April 8, 2020 and March 7, 2021 in PsycInfo and PubMed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Manuscripts were screened against eligibility criteria and were included if they investigated psychological symptoms in children or adolescents (age between 1 to 21 years at the time of study) who were hospitalized for pediatric surgery. Means and standard deviations weighted by sample size were calculated. Eleven articles met inclusion criteria. The review revealed that a small but substantial number of children and adolescents are at an elevated risk for postoperative psychological symptoms and disorders. Up to 13% had symptoms consistent with a diagnosis of a posttraumatic stress disorder, 6% to 8% exhibited elevated symptoms of depression or anxiety, and about 25% showed internalizing and externalizing symptoms. This review provides preliminary evidence that children and adolescents experience significant psychological distress and posttraumatic stress symptoms after pediatric surgery. Apart from better training of clinicians, prevention, early psychological screening and psychosocial care in surgical wards of hospitals are recommended. Well-designed studies of high methodological quality are necessary to replicate existing findings and provide a broader base of evidence.
Time-critical decentralised situational awareness in emergencies: an adversarial biosecurity scenario
Authors: Bassett Jason , Pescetelli Niccolò , Rutherford Alex , Cebrian Manuel 
Published: August 2021

AbstractCrises in a global setting of interdependencies call for time-critical coordinated responses. However, it is often the case that the mechanisms responsible for these actions do not agree across all their hierarchies. This can be roughly attributed to personal estimations of the situation and to social influence. An ensuing lack of consensus against crises can be dire and echo across entire populations. One such instance is the case of biosecurity threats. A particularly interesting class of threats lie within urban environments, which tend to fall within the scope of bad actors. With this work we aim to computationally contribute to the understanding of the dynamics of perceived danger formation among agents responsible for responding to ongoing biological attacks in urban settings. We assume this perception is a function of a personal estimation of local information about the danger and of social influence stemming from the agents in question framed in an agent-based model. The simulations point towards a high dependence of perceived dangers on the personal estimations of the agents. The conditions under which the perceived dangers deviate from the real ones are explored over a range of assumptions on personal measurements and several dispositions towards the influencing environment. The insight provided by these results at the individual and collective level set the tone for further investigation on such behavioural phenomena, providing a flexible computational framework addressing generic threats (true dangers) in a time-critical context.
Association between clinical frailty, illness severity and post-discharge survival: a prospective cohort study of older medical inpatients in Norway
Authors: Engvig Andreas , Wyller Torgeir Bruun , Skovlund Eva , Ahmed Marc Vali , Hall Trygve Sundby , Rockwood Kenneth , Njaastad Anne Mette , Neerland Bjørn Erik 
Published: August 2021

Abstract
Purpose
Study associations between frailty, illness severity and post-discharge survival in older adults admitted to medical wards with acute clinical conditions.

Methods
Prospective cohort study of 195 individuals (mean age 86; 63% females) admitted to two medical wards with acute illness, followed up for all-cause mortality for 20 months after discharge. Ward physicians screened for frailty and quantified its degree from one to eight using Clinical Frailty Scale (CFS), while clinical illness severity was estimated by New Early Warning Score 2 (NEWS2) and laboratory illness severity was calculated by a frailty index (FI-lab) using routine blood tests.

Results
CFS, NEWS2 and FI-lab scores were independently associated with post-discharge survival in an adjusted Cox proportional hazards model with age, ward category (acute geriatric and general medical) and comorbidity as covariates. Adjusted hazard ratios and 95% confidence intervals were 1.54 (1.24–1.91) for CFS, 1.12 (1.03–1.23) for NEWS2, and 1.02 (1.00–1.05) for FI-lab. A frailty × illness severity category interaction effect (p = 0.003), suggested that the impact of frailty on survival was greater in those experiencing higher levels of illness severity. Among patients with at least moderate frailty (CFS six to eight) and high illness severity according to both NEWS2 and FI-lab, two (13%) were alive at follow-up.

Conclusion
Frailty screening aided prognostication of survival following discharge in older acutely ill persons admitted to medical wards. The prognostic value of frailty increased when combined with readily available illness severity markers acquired during admission.
Hudson Strait Inflow: Structure and Variability
Authors: Ridenour Natasha A. , Straneo Fiammetta , Holte James , Gratton Yves , Myers Paul G. , Barber David G. 
Published: August 2021

AbstractHudson Strait is the main pathway of heat, mass, and freshwater exchange between Hudson Bay and the Arctic and North Atlantic oceans. The outflow along the southern coast of the strait, a fresh, baroclinic jet directed toward the North Atlantic, has received more attention due to its potential impact on deep convection in the Labrador Sea. However, details about the westward, more barotropic inflow along the northern coast of Hudson Strait remain unknown due to a scarcity of observations. Hudson Strait inflow waters affect the physical and biogeochemical systems of the bay, as well as the marine ecosystem, which supports the livelihoods of many Indigenous communities surrounding the Hudson Bay region. Here, we address this knowledge gap by analyzing data from two hydrographic surveys and four moorings deployed across the strait from 2008 and 2009. Three moorings were deployed on the northern side of the strait to map the inflow, and one was deployed on the southern side of the strait to capture the outflow. Along the southern side, a stratified, fresh outflow was observed, consistent with earlier studies. Along the northern coast, the inflow is weakly stratified and more saline, with seasonal changes distributed throughout the water column. Source waters of the inflow stem mainly from Arctic Water in the Baffin Island Current. A comparison with historical data suggests that after modification in western Hudson Strait, part of the inflow enters northern Hudson Bay to become deep water in the bay.
Response of Bacterial Communities to Rainwater Additions in the Oligotrophic SE Mediterranean Coast; Experimental and In‐Situ Observations
Authors: Rahav Eyal , Gertner Yaron , Herut Barak 
Published: August 2021

AbstractWet deposition may serve as a source of external nutrients for phytoplankton and heterotrophic bacteria in low nutrients low chlorophyll (LNLC) marine systems. Here, we examined the effects of rainwater deposition on phytoplankton and bacterial abundance and activity in the LNLC SE Mediterranean coast. In‐situ observations and experimentally controlled incubations show enhanced abundance and productivity of the bacterioplankton communities attributed to the addition of rainwater‐born nutrients. While rainwater relieved N limitation to phytoplankton resulting in enhanced abundance and primary production of autotrophic microbial communities (mostly pico‐eukaryotes), no single nutrient (N or P) could be identified as a sole limiting factor of the stimulated heterotrophic bacteria. In both the experimental and in‐situ observations, the changes in phytoplankton biomass following rainwater deposition/addition was observed only after 24–48 h. Contrary, an increase in primary and bacterial productions was visible within a few hours, suggesting high nutrients turnover rates by bacterioplankton communities following rain deposition. These results emphasize the importance of short‐term wet deposition events to new N production and phytoplankton temporal variability in the LNLC SE Mediterranean coast.
Reconstruction of Historical Land Surface Albedo Changes in China From 850 to 2015 Using Land Use Harmonization Data and Albedo Look‐Up Maps
Authors: Song Yan , Lv Mingzhu , Wang Mengsi , Li Xijia , Qu Ying 
Published: August 2021

AbstractLand surface albedo is a critical parameter of the Earth's energy budget and has been greatly altered by climate change and human activities. To improve our understanding of historical land surface albedo changes and their climatic effects before the satellite remote sensing era, we reconstructed land surface albedo in China from 850 to 2015 using the historical land use harmonization version 2 (LUH2) data set and albedo look‐up maps, and estimated the radiative forcing induced by land surface albedo changes using atmospheric radiative kernels. The reconstruction results showed that the annual‐mean land surface albedo in China increased by 0.00110 during 850–2015, and the rate of increase was accelerated by the expansion of croplands during recent centuries. The most significant increases in land surface albedo were found in the Huang‐Huai‐Hai (HHH; +0.00646) and Northeast China (NE; +0.00501), which were primarily driven by anthropogenic land cover transformations (e.g., land reclamation, deforestation, and urbanization) and can be enhanced by the vegetation masking effect on snow cover. The radiative forcing induced by land surface albedo changes in China during 850–2015 and 1750–2015 was −0.09 ± 0.04 and −0.06 ± 0.02 W m−2, respectively, which indicated that the land surface albedo changes produced a slight climate cooling effect, helping to offset the warming effect caused by greenhouse gas emissions.
Carbonatite Versus Silicate Melt Metasomatism Impacts Grain Scale 87Sr/86Sr and 143Nd/144Nd Heterogeneity in Polynesian Mantle Peridotite Xenoliths
Authors: Byerly Benjamin L. , Jackson M. G. , Bizimis M. 
Published: August 2021

AbstractThe Earth's upper mantle is isotopically heterogeneous over large lengthscales, but the lower limit of these heterogeneities is not well quantified. Grain scale trace elemental variability has been observed in mantle peridotites, which suggests that isotopic heterogeneity may be preserved as well. Recent advances in isotope ratio mass spectrometry enable isotopic analysis of very small samples (e.g., nanograms or less of analyte) while maintaining the precision necessary for meaningful interpretation. Here we examine four peridotite xenoliths—hosted in lavas from Savai'i (Samoa hotspot) and Tahiti (Societies hotspot) islands—that exhibit grain scale trace element heterogeneity likely related to trapped fluid and/or melt inclusions. To evaluate whether this heterogeneity is also reflected in grain scale isotopic heterogeneity, we separated clinopyroxene, orthopyroxene, and (in the most geochemically enriched xenolith) olivine for single‐grain 87Sr/86Sr and 143Nd/144Nd analyses. We find, in some xenoliths, extreme intra‐xenolith isotopic heterogeneity. For example, in one xenolith, different mineral grains range in 87Sr/86Sr from 0.70987 to 0.71321, with corresponding variability in 143Nd/144Nd from 0.512331 to 0.512462. However, not all peridotite xenoliths which display trace elemental heterogeneity exhibit isotopic heterogeneity. Based on coupled isotopic and trace element data (i.e., a negatively‐sloping trend in 87Sr/86Sr vs. Ti/Eu), we suggest that carbonatitic metasomatism is responsible for creating the intra‐xenolith isotopic heterogeneities which we observe. This carbonatitic component falls off the array defined in 87Sr/86Sr‐143Nd/144Nd space by Samoa hotspot basalts, which suggests a second, distinct EM2 (enriched mantle II) component is present in the Samoa hotspot that is not readily recognized in erupted products, but is instead seen only in mantle peridotite xenoliths.
A New Method to Calculate the Fluxgate Magnetometer Offset in the Interplanetary Magnetic Field: 2. Using Mirror Mode Structures
Authors: Wang Guoqiang , Pan Zonghao 
Published: August 2021

AbstractAccurate magnetic field measurement is of great significance to the development of space exploration. The fluxgate magnetometer (FGM) is a magnetic field measuring instrument commonly used on the spacecraft. The zero offset of the spaceborne FGM varies slowly with time, thus it needs to be regularly calibrated. Here, we develop a new method to determine the zero offset of the FGM using mirror mode structures. This method is based on an assumption that the magnetic depression of mirror mode structures is only in the maximum variance direction. We find that each mirror mode structure has an optimal offset line (OOL), which is determined by the minimum strength of the modified magnetic field in the plane perpendicular to the maximum variance direction in an offset cube. The OOL is approximately parallel to the maximum variance direction and passes through the zero offset in the offset cube. The common intersection of at least two non‐parallel OOLs can be regarded as the zero offset, which accuracy tends to be higher with more events. Our method can simultaneously use the mirror modes and Alfvén waves, and is able to be applied to many regions, such as solar wind, planetary magnetosheaths and magnetospheres.