bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling the effects of capillary pressure with the presence of full tensor permeability and discrete fracture models using the mimetic finite difference method
Authors: Abd Abdul Salam , Zhang Na , Abushaikha Ahmad S.
Published: March 2021

Capillary dominated flow or imbibition—whether spontaneous or forced—is an important physical phenomena in understanding the behavior of naturally fractured water-driven reservoirs (NFR’s). When the water flows through the fractures, it imbibes into the matrix and pushes the oil out of the pores due to the difference in the capillary pressure. In this paper, we focus on modeling and quantifying the oil recovered from NFR’s through the imbibition processes using a novel fully implicit mimetic finite difference (MFD) approach coupled with discrete fracture/discrete matrix (DFDM) technique. The investigation is carried out in the light of different wetting states of the porous media (i.e., varying capillary pressure curves) and a full tensor representation of the permeability. The produced results proved the MFD to be robust in preserving the physics of the problem, and accurately mapping the flow path in the investigated domains. The wetting state of the rock affects greatly the oil recovery factors along with the orientation of the fractures and the principal direction of the permeability tensor. We can conclude that our novel MFD method can handle the fluid flow problems in discrete-fractured reservoirs. Future works will be focused on the extension of MFD method to more complex multi-physics simulations.
MIMO-employed coherent photonic-radar (MIMO-Co-PHRAD) for detection and ranging
Authors: Sharma Vishal , Kbashi Hani J. , Sergeyev Sergey
Published: March 2021

Recently, the photonics-radar technology comes out as an attractive candidate in the arena of smart autonomous transportation, surveillance, and navigation-related applications owing to provide wide-spectra to attain improved and precise radar-resolutions. On the other hand, microwave radars, due to limited bandwidth, are incapable of coping with the demands of next-generation radar technology. Moreover, the atmospheric fluctuations become more prominent at higher frequencies and affect the radar’s performance significantly. Subsequently, the authors develop a 2 × 2 multi-input multi-output (MIMO) employed linear frequency-modulated continuous-wave coherent photonic-radar system (MIMO-Co-PHRAD) using OptiSystem™ and MATLAB™ to attain a prolonged detection-range with an enhanced visibility. The developed MIMO-Co-PHRAD is investigated with heterodyne- and homodyne-detection approaches under weak-to-strong regimes of the atmospheric fluctuations like Rain and Fog. A comparison is also drawn for both the demonstrated MIMO-equipped laser-driven coherent photonic-radar systems. The performance of both the developed MIMO-Co-PHRAD systems is evaluated by measuring the intensity of reflected-echoes, signal-to-noise ratio, and range-Doppler patterns. A contrast with the single-input single-output coherent photonic-radar (SISO-Co-PHRAD) is also established to validate the robustness of the demonstrated MIMO-Co-PHRAD.
Admission criteria for a cardiovascular short stay unit: a retrospective analysis on a pilot unit
Authors: Capone Federico , Molinari Leonardo , Noale Marianna , Previato Lorenzo , Giannini Sandro , Vettore Gianna , Fabris Fabrizio , Saller Alois
Published: March 2021

Rapid intensive observation (RIO) units have been created to guarantee high standards of care in a sustainable health-care system. Within short stay units (SSUs), which are a subgroup of RIOs, only rapidly manageable patients should be admitted. Physicians are unable to predict the length of stay (LOS) as objective criteria to make such a prediction are missing. A retrospective observational study was carried out to identify the objective criteria for admission within a cardiovascular care-oriented SSU. Over a period of 317 days, 340 patients (age 69.4 ± 14.7 years) were admitted to a pilot SSU within our internal medicine department. The most frequent diagnoses were chest pain (45.9%), syncope (12.9%), and supraventricular arrhythmias (11.2%). The median LOS was 4 days (quartile 1:3; quartile 3:7). Predictors of LOS ≤ 96 h were age < 80, hemoglobin > 115 g/L, estimated glomerular filtration rate > 45 mL/min/1.73 m2, Charlson Comorbidity Index < 3, Barthel Index > 40, diagnosis of chest pain, syncope, supraventricular arrhythmias, or acute heart failure. The HEART (history, ECG, age, risk factors, troponin) score was found to be excellent in risk stratification of patients admitted for chest pain. Blood tests and anamnestic variables can be used to predict the LOS and thus SSU admission. The HEART score may help in the classification of patients with chest pain admitted to an SSU.
A phase-locked loop using ESO-based loop filter for grid-connected converter: performance analysis
Authors: Guo Baoling , Bacha Seddik , Alamir Mazen , Pouget Julien
Published: March 2021

An extended state observer (ESO)-based loop filter is designed for the phase-locked loop (PLL) involved in a disturbed grid-connected converter (GcC). This ESO-based design enhances the performances and robustness of the PLL, and, therefore, improves control performances of the disturbed GcCs. Besides, the ESO-based LF can be applied to PLLs with extra filters for abnormal grid conditions. The unbalanced grid is particularly taken into account for the performance analysis. A tuning approach based on the well-designed PI controller is discussed, which results in a fair comparison with conventional PI-type PLLs. The frequency domain properties are quantitatively analysed with respect to the control stability and the noises rejection. The frequency domain analysis and simulation results suggest that the performances of the generated ESO-based controllers are comparable to those of the PI control at low frequency, while have better ability to attenuate high-frequency measurement noises. The phase margin decreases slightly, but remains acceptable. Finally, experimental tests are conducted with a hybrid power hardware-in-the-loop benchmark, in which balanced/unbalanced cases are both explored. The obtained results prove the effectiveness of ESO-based PLLs when applied to the disturbed GcC.
Ethical Implications of eHealth Tools for Delivering STI/HIV Laboratory Results and Partner Notifications
Authors: Godongwana Motlatso , Chewparsad Juanita , Lebina Limakatso , Golub Jonathan , Martinson Neil , Jarrett Brooke A.
Published: March 2021

Purpose of Review

eHealth tools are increasingly utilized for communication with patients. Although efficacious and cost-effective, these tools face several barriers that challenge their ethical use in sexual health. We reviewed literature from the past decade to pick illustrative studies of eHealth tools that deliver results of laboratory tests for sexually transmitted infections, including the human immunodeficiency virus, as well as partner notifications. We describe ethical implications for such technologies.

Recent Findings

Our review found that despite widespread research on the use of eHealth tools in delivering laboratory results and partner notifications, these studies rarely measured or reported on the ethical implications. Such implications can be organized according to the four major principles in bioethics: beneficence, patient autonomy, non-maleficence, and justice. The beneficence of eHealth typically measures efficacy in comparison to existing standards of care. Patient autonomy includes the ability to opt in or out of eHealth tools, right-based principles of consent, and sovereignty over healthcare data. To adhere to the principle of non-maleficence, relevant harms must be identified and measured—such as unintentional disclosure of illness, sexual orientation, or sexual activity. Justice must also be considered to accommodate all users equally, irrespective of their literacy level, with easy-to-use platforms that provide clear messages.

Based on case studies from this review, we developed a list of recommendations for the ethical development and evaluation of eHealth platforms to deliver STI/HIV results to patients and notifications to partners.
1H, 13C, and 15N backbone chemical-shift assignments of SARS-CoV-2 non-structural protein 1 (leader protein)
Authors: Wang Ying , Kirkpatrick John , zur Lage Susanne , Korn Sophie M. , Neißner Konstantin , Schwalbe Harald , Schlundt Andreas , Carlomagno Teresa
Published: March 2021

The current COVID-19 pandemic caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has become a worldwide health crisis, necessitating coordinated scientific research and urgent identification of new drug targets for treatment of COVID-19 lung disease. The covid19-nmr consortium seeks to support drug development by providing publicly accessible NMR data on the viral RNA elements and proteins. The SARS-CoV-2 genome comprises a single RNA of about 30 kb in length, in which 14 open reading frames (ORFs) have been annotated, and encodes approximately 30 proteins. The first two-thirds of the SARS-CoV-2 genome is made up of two large overlapping open-reading-frames (ORF1a and ORF1b) encoding a replicase polyprotein, which is subsequently cleaved to yield 16 so-called non-structural proteins. The non-structural protein 1 (Nsp1), which is considered to be a major virulence factor, suppresses host immune functions by associating with host ribosomal complexes at the very end of its C-terminus. Furthermore, Nsp1 facilitates initiation of viral RNA translation via an interaction of its N-terminal domain with the 5′ untranslated region (UTR) of the viral RNA. Here, we report the near-complete backbone chemical-shift assignments of full-length SARS-CoV-2 Nsp1 (19.8 kDa), which reveal the domain organization, secondary structure and backbone dynamics of Nsp1, and which will be of value to further NMR-based investigations of both the biochemical and physiological functions of Nsp1.
Poincaré Inequality on Subanalytic Sets
Authors: Valette Anna , Valette Guillaume
Published: March 2021

Let$$\Omega $$Ωbe a subanalytic connected bounded open subset of$$\mathbb {R}^n$$Rn, with possibly singular boundary. We show that given$$p\in [1,\infty )$$p∈[1,∞), there is a constantCsuch that for any$$u\in W^{1,p}(\Omega )$$u∈W1,p(Ω)we have$$||u-u_{\Omega }||_{L^p} \le C||\nabla u||_{L^p},$$||u-uΩ||Lp≤C||∇u||Lp,where we have set$$u_{\Omega }:=\frac{1}{|\Omega |}\int _{\Omega } u.$$uΩ:=1|Ω|∫Ωu.
Development of a multi-mycotoxin LC-MS/MS method for the determination of biomarkers in pig urine
Authors: Tkaczyk Agnieszka , Jedziniak Piotr
Published: March 2021

An LC-MS/MS method has been developed for the sensitive and selective determination of 35 mycotoxins (biomarkers of exposure) in pig urine samples. Sample preparation includes creatinine adjustment (with the developed LC-UV method) with enzymatic hydrolysis of pig urine samples followed by liquid-liquid (LLE) extraction. The LLE protocol, as well as enzymatic hydrolysis for indirect mycotoxin glucuronides determination, was optimized in this study. Additionally, two other sample preparation protocols were compared with the developed LLE method: immunoaffinity columns and solid-phase extraction cartridges (Oasis HLB). The detection and quantification of the biomarkers were performed using triple quadrupole mass spectrometry.

The method was validated with regard to the guidelines specified by the EMEA (European Medicines Agency). The extraction recoveries were higher than 60% for 77% of the analytes studied, with the intra- and inter-day relative standard deviation being lower than 20% for most of the compounds at four different concentration levels. The limits of quantification ranged from 0.1 ng/mL for zearalenone and sterigmatocystin to 8 ng/mL for nivalenol. To the best knowledge of the authors, the matrix effect was evaluated for the first time in this study for six different urine samples, and the coefficient of variation was found to be lower than 15% for most analytes studied. Finally, the developed method was applied to analyse 56 pig urine samples. Deoxynivalenol (1–20 ng/mL), zearalenone (0.1–1.5 ng/mL) and ochratoxin A (1.5–15 ng/mL) were the main analytes detected in these samples. Moreover, the co-occurrence of alternariol monomethyl ether and alternariol in pig urine is reported herein for the first time.
Varying-Coefficient Stochastic Differential Equations with Applications in Ecology
Authors: Michelot Théo , Glennie Richard , Harris Catriona , Thomas Len
Published: March 2021

Stochastic differential equations (SDEs) are popular tools to analyse time series data in many areas, such as mathematical finance, physics, and biology. They provide a mechanistic description of the phenomenon of interest, and their parameters often have a clear interpretation. These advantages come at the cost of requiring a relatively simple model specification. We propose a flexible model for SDEs with time-varying dynamics where the parameters of the process are nonparametric functions of covariates, similar to generalized additive models. Combining the SDE and nonparametric approaches allows for the SDE to capture more detailed, non-stationary, features of the data-generating process. We present a computationally efficient method of approximate inference, where the SDE parameters can vary according to fixed covariate effects, random effects, or basis-penalty smoothing splines. We demonstrate the versatility and utility of this approach with three applications in ecology, where there is often a modelling trade-off between interpretability and flexibility.

Supplementary materials accompanying this paper appear online.
Spatiotemporal patterns of red fox scavenging in forest and tundra: the influence of prey fluctuations and winter conditions
Authors: Gomo Gjermund , Mattisson Jenny , Rød-Eriksen Lars , Eide Nina E. , Odden Morten
Published: March 2021

Concern has been raised regarding red fox (Vulpes Vulpes) population increase and range expansion into alpine tundra, directly and indirectly enhanced by human activities, including carrion supply, and its negative impact on native fauna. In this study, we used cameras on bait stations and hunting remains to investigate how spatiotemporal patterns of red fox scavenging were influenced by abundance and accessibility of live prey, i.e., small rodent population cycles, snow depth, and primary productivity. We found contrasting patterns of scavenging between habitats during winter. In alpine areas, use of baits was highest post rodent peaks and when snow depth was low. This probably reflected relatively higher red fox abundance due to increased reproduction or migration of individuals from neighboring areas, possibly also enhanced by a diet shift. Contrastingly, red fox use of baits in the forest was highest during rodent low phase, and when snow was deep, indicating a higher dependency of carrion under these conditions. Scavenging patterns by red fox on the pulsed but predictable food resource from hunting remains in the autumn revealed no patterns throughout the rodent cycle. In this study, we showed that small rodent dynamics influenced red fox scavenging, at least in winter, but with contrasting patterns depending on environmental conditions. In marginal alpine areas, a numerical response to higher availability of rodents possible lead to the increase in bait visitation the proceeding winter, while in more productive forest areas, low availability of rodents induced a functional diet shift towards scavenging.
Alterations in mucosa-associated microbiota in the stomach of patients with gastric cancer
Authors: Deng Yilin , Ding Xuewei , Song Qingyuan , Zhao Gang , Han Lei , Ding Bowen , Wang Xianhao , Hao Xishan , Li Hui
Published: March 2021

Purpose

The purpose of this study was to characterize alterations in mucosa-associated microbiota in different anatomical locations of the stomach during gastric cancer progression and to identify associations between Helicobacter pylori infection and gastric microbial changes in patients with gastric cancer.

Methods

Twenty-five H. pylori negative subjects with chronic gastritis and thirty-four subjects with gastric cancer were recruited, including H. pylori negative and positive patients with tumors in the antrum and the corpus. Gastric mucosa-associated microbiota were determined by 16S ribosomal RNA gene sequencing using a 454 sequencing platform.

Results

We found that individuals with chronic gastritis from three different anatomical sites exhibited different microbiota compositions, although the microbial alpha diversity, richness and beta diversity were similar. Compared to patients with chronic gastritis, the gastric microbiota compositions were significantly different at the order level in the antrum and the corpus of patients with gastric cancer, which was dependent on the H. pylori infection status. Microbial alpha diversity and species richness, however, were similar between chronic gastritis and gastric cancer cases and independent of H. pylori status. The microbial community structure in patients with gastric cancer was distinct from that in patients with chronic gastritis. In addition, we found that the presence of H. pylori markedly altered the structure in gastric corpus cancer, but only mildly affected the antrum.

Conclusion

Our data revealed distinct niche-specific microbiota alterations during the progression from gastritis to gastric cancer. These alterations may reflect adaptions of the microbiota to the diverse specific environmental habitats in the stomach, and may play an important, as yet undetermined, role in gastric carcinogenesis.
Comparison of thermochemical treatment of sewage sludge ash with sodium sulphate in laboratory-scale and pilot-scale experiments
Authors: Herzel H. , Stemann J. , Simon S. , Adam C.
Published: March 2021

There is an ongoing debate on European scale concerning the criticality of phosphorus. In Switzerland and Germany, phosphorus recovery from phosphorus-rich waste streams will become obligatory. Sewage sludge ash is rich in phosphorus and may become an important secondary feedstock. Thermochemical treatment of sewage sludge ash with sodium sulphate under reducing conditions was shown to remove heavy metals from the solid product and produce the fully plant available crystalline phase CaNaPO4. Pilot-scale experiments in a rotary kiln were carried out at temperatures between 750 and 1000 °C and were compared to laboratory-scale experiments with crucibles. Process upscaling was successfully demonstrated but a series of differences were noticed: In comparison to laboratory-scale, solubility of phosphorus in samples from pilot-scale experiments was lower at all chosen treatment temperatures because of shorter retention time and incomplete decomposition of sodium sulphate. X-ray diffraction analysis revealed remaining phase fractions of whitlockite (Ca3-x(Mg,Fe)x(PO4)2) and sodium sulphate from the starting materials in products and thus indicated incomplete reaction. In contrast to the results of laboratory-scale experiments, the crystalline phase CaNaPO4 was clearly absent in the products from the rotary kiln but instead a Mg-bearing phase (Ca,Mg)NaPO4 was formed. Laboratory-scale experiments confirmed (Ca,Mg)NaPO4 is an intermediate phase between whitlockite and CaNaPO4. However, both crystalline phases are characterized by high plant availability. It was shown that heavy metal removal increased at higher temperatures whereas solubility and thus plant availability of phosphorus already reached its maxima at temperatures of 950 °C in pilot-scale and 875 °C in laboratory-scale experiments.
Front-of-pack nutrition labelling in the European Union: a behavioural, legal and political analysis
Authors: DELHOMME Vincent
Published: March 2021

Amidst a growing interest from European Union (EU) Member States, the European Commission recently announced that it would put forward a legislative proposal for the adoption of a harmonised and mandatory front-of-pack nutrition labelling scheme at the EU level. The present contribution discusses the implications of such an adoption, taking a behavioural, legal and policy angle. It introduces first the concept of front-of-pack nutrition labelling and the existing evidence regarding its effects on consumer behaviour and dietary habits. It then presents the legal framework currently applicable to (front-of-pack) nutrition labelling in the EU and discusses some of the main political and practical aspects involved with the development of a common EU front-of-pack label.
The first records of mollusks from mid-Cretaceous Hkamti amber (Myanmar), with the description of a land snail, Euthema myanmarica n. sp. (Caenogastropoda, Cyclophoroidea, Diplommatinidae)
Authors: Balashov Igor
Published: March 2021

Five land snails and the borings of marine bivalves are reported from Hkamti (Khamti) amber whose age was recently uranium-lead dated to be ca. 110 Ma, in contrast to the nearby Kachin (‘Burmese’) amber considered to be ca. 99 Ma. Four of the snails belong to Cyclophoridae, and although their condition does not allow unambiguous identification or description of the species, one of them strongly resembles Archaeocyclotus plicatula Asato and Hirano in Hirano et al., 2019 from Kachin amber. The fifth snail, Euthema myanmarica n. sp. (Diplommatinidae), is a representative of a genus that was known exclusively from Kachin amber until now. The genus Euthema Yu, Wang, and Pan, 2018 is revised, with a new synonym, Xenostoma Bullis et al., 2020. The recently described ‘Truncatellina dilatatus’ Yu, 2020 from Kachin amber is placed in Euthema. A comparison of the distinguishing characters of the eight Euthema species is provided. The borings of bivalves in Hkamti amber correspond to the ichnospecies Teredolites clavatus Leymerie, 1842, associated with the bivalve genus Martesia Sowerby, 1824 (Pholadidae), and are common in Kachin amber. Similarity of the malacofauna from Hkamti and Kachin ambers, as well as the presence of numerous, similar Teredolites clavatus, indicates that these ambers were formed in very similar paleoenvironments. This indication suggests that forests with very similar conditions existed throughout the entire Albian to the early Cenomanian, or that the dating of at least one of these amber deposits is incorrect. In the latter case, it would mean that Kachin amber is at least 110 Ma or older.

UUID: http://zoobank.org/142f10a2-307f-4053-9b29-8aa18db66219
‘The moustache’ returns: referential metonymy acquisition in adult learners of English as an additional language (EAL)
Authors: BOWERMAN JOSEPHINE , FALKUM INGRID LOSSIUS , POUSCOULOUS NAUSICAA
Published: March 2021

abstract

Referential metonymy, e.g. ‘the moustache(= man with a moustache) sits down first’, appears early in L1 acquisition (Falkum, Recasens & Clark, 2017). Yet how does it emerge in pragmatically mature but linguistically developing adult L2 learners? We used one comprehension and two production tasks, based on Falkum and colleagues (2017), to investigate metonymy abilities in 34 Japanese adult learners of English as an additional language (EAL) and a control group of 31 native English speakers. We also examined how time constraints and exposure to examples of referential metonymy affected production. In the comprehension task, both EAL-learner and native-speaker participants chose metonymic readings at above chance levels. In both production tasks, all participants produced innovative metonyms. Additionally, the findings indicate that, in L2, exposure to examples dramatically increases metonymy production, while time pressure decreases it. The results suggest that participants can both comprehend and produce novel metonyms in L2, with a possible explicitness vs. production costs trade-off.
Geographic contingency, not species sorting, dominates macroevolutionary dynamics in an extinct clade of neogastropods (Volutospina; Volutidae)
Authors: Friend Dana S. , Anderson Brendan M. , Allmon Warren D.
Published: March 2021

Rates of speciation and extinction are often linked to many ecological factors, traits (emergent and nonemergent) such as environmental tolerance, body size, feeding type, and geographic range. Marine gastropods in particular have been used to examine the role of larval dispersal in speciation. However, relatively few studies have been conducted placing larval modes in species-level phylogenetic context. Those that have, have not incorporated fossil data, while landmark macroevolutionary studies on fossil clades have not considered both phylogenetic context and net speciation (speciation–extinction) rates. This study utilizes Eocene volutid Volutospina species from the U.S. Gulf Coastal Plain and the Hampshire Basin, U.K., to explore the relationships among larval mode, geographic range, and duration. Based on the phylogeny of these Volutospina, we calculated speciation and extinction rates in order to compare the macroevolutionary effects of larval mode. Species with planktotrophic larvae had a median duration of 9.7 Myr, which compared significantly to 4.7 Myr for those with non-planktotrophic larvae. Larval mode did not significantly factor into geographic-range size, but U.S. and U.K. species do differ, indicating a locality-specific component to maximum geographic-range size. Non-planktotrophs (NPTs)were absent among the Volutospina species during the Paleocene–early Eocene. The relative proportions of NPTs increased in the early middle Eocene, and the late Eocene was characterized by disappearance of planktotrophs (PTs). The pattern of observed lineage diversity shows an increasing preponderance of NPTs; however, this is clearly driven by a dramatic extinction of PTs, rather than higher NPT speciation rates during the late Eocene. This study adds nuance to paleontology's understanding of the macroevolutionary consequences of larval mode.
Illiberalism
Authors: Kauth Jasper Theodor , King Desmond
Published: March 2021

“Illiberalism” has assumed an invigorated if unanticipated significance in the 21st century. Aspects of illiberalism populate not only states long known as indifferent to such principles as personal liberty, human equality and the rule of law but have expanded in “liberal” democracies as their rulers employ purportedly “illiberal” practices more frequently than in the recent past. Indeed, the term “illiberal” seems to have lost its negative aura in the context of state action. We contend that illiberalism represents either an opposition to procedural democratic norms—asdisruptive illiberalism—or an ideological struggle—termedideological illiberalism.We first discuss the term as used in the vast literature on regime types in the debate on authoritarian/democratic hybrid-regimes. We then turn to the key puzzle in what one may call “illiberalism studies”: the rise of illiberal practices and policies in liberal democracies. To inform our analysis empirically, we investigate the ways in which illiberal arguments and institutions (notably camps) were deployed historically and in immigration policy. We conclude with an example of illiberal policy from modern day Hungary.
Selection of insectary plants for the conservation of biological control agents of aphids and thrips in fruit orchards
Authors: Denis Carmen , Riudavets Jordi , Gabarra Rosa , Molina Paula , Arnó Judit
Published: March 2021

This study evaluated the potential of flowering plant species naturally occurring to promote the conservation and early establishment of key natural enemies of aphids and thrips in apple and peach orchards. Flowering plants present in the North East of Spain, a main fruit production area in Europe, were sampled to determine their flowering period and to identify potential natural enemies present on each plant species. Thirty-six plant species were found blooming from early March to late May and provided an array of flowers that might ensure food resources for natural enemies. Among them, six species – Eruca vesicaria (L.) Cav., Cardaria draba (L.) Desv., Euphorbia serrata (L.) S.G. Gmel., Malva sylvestris L., Anacyclus clavatus (Desf.) Pers. and Diplotaxis erucoides (L.) DC. – hosted a high diversity of potential natural enemies of aphids and thrips. Their blooming started early in the season and lasted for several sampling weeks and they were widely distributed. Moreover, they had available nectar even in those species with protected nectaries. Therefore, these plant species can be considered as promising candidates for inclusion in the ecological infrastructure designed for fruit orchards in the study area to promote the conservation of the biological control agents of aphids and thrips.
NEGLECTED EVIDENCE FOR ARISTOTLE, HISTORIA ANIMALIVM 7(8) IN THE WORKS OF ANCIENT HOMERIC SCHOLARS
Authors: Mayhew Robert
Published: March 2021

This brief article aims to supplement Stefan Schnieders's presentation of the evidence for Historia animalium 7(8)—that is, Book 7 according to the manuscript tradition, Book 8 according to Theodore Gaza's rearrangement—having been considered the seventh book of this work in antiquity. This is accomplished through the discussion of two texts not considered by Schnieders, both of them passages commenting on Iliad Book 21: P.Oxy. 221 (col. X 11–14) and Porphyry, Homeric Questions Book 1 (§8, page 43.8–14 Sodano).
Effect of driving frequency on dust particle dynamics in radiofrequency capacitive argon discharge
Authors: Missaoui Abdelhak , El kaouini Morad , Chatei Hassan
Published: March 2021

This paper investigates the influence of the driving frequency on the dynamics of a single dust particle in argon radiofrequency discharge. A one-dimensional fluid model is presented and solved in the entire inter-electrode domain using the finite difference method. In order to solve the particle equation of motion, the coefficients describing the amplification and the damping of the dust particle oscillations are analytically calculated around the equilibrium position, these coefficients allow us to find the relation between the plasma and dust parameters. The results obtained cover the discharge characteristics, the charge and the dynamics of the dust particle. It has been found that the driving frequency has a significant effect on not only the discharge properties but also on the damped oscillatory motion and the equilibrium position of the dust particle. Hence, these oscillations become closer to the electrodes with increasing driving frequency whereas the dust equilibrium position becomes relatively farther from the powered electrode when the dust size decreases.
Two new Pseudoceros (Platyhelminthes: Polycladida: Pseudocerotidae) from Agatti Island, India and a species checklist from Indian waters
Authors: Dixit Sudhanshu , Manjebrayakath Hashim , Saravanane Narayanane
Published: March 2021

The Lakshadweep archipelago constitutes a major coral region of India but still lacks sufficient biodiversity data owing to its remoteness and a low number of faunal studies in the past. The present paper describes two new Pseudoceros species collected from Agatti Island, Lakshadweep, India. Pseudoceros bipurpurea sp. nov. and Pseudoceros galaxea sp. nov. are described based on external and internal characters, supported with histological studies and photographs. Pseudoceros bipurpurea sp. nov. is characterized by a cream background colour and an orange median line surrounded by dense patches of purple spots, which tend to disperse and broaden towards the posterior end. Pseudoceros galaxea sp. nov. displays a brown background colour with numerous white to cream dots covering almost the entire dorsal surface and a thin black margin. This study adds two new species to the polyclad fauna in Indian waters, raising the count to 68 species. An updated checklist of polyclads from Indian coast is also provided.
Maternal health around pregnancy and autism risk: a diagnosis-wide, population-based study
Authors: Kodesh Arad , Levine Stephen Z. , Khachadourian Vahe , Rahman Rayees , Schlessinger Avner , O'Reilly Paul F. , Grove Jakob , Schendel Diana , Buxbaum Joseph D. , Croen Lisa , Reichenberg Abraham , Sandin Sven , Janecka Magdalena
Published: March 2021

Background

Many studies have reported an increased risk of autism spectrum disorder (ASD) associated with some maternal diagnoses in pregnancy. However, such associations have not been studied systematically, accounting for comorbidity between maternal disorders. Therefore our aim was to comprehensively test the associations between maternal diagnoses around pregnancy and ASD risk in offspring.

Methods

This exploratory case–cohort study included children born in Israel from 1997 to 2008, and followed up until 2015. We used information on all ICD-9 codes received by their mothers during pregnancy and the preceding year. ASD risk associated with each of those conditions was calculated using Cox proportional hazards regression, adjusted for the confounders (birth year, maternal age, socioeconomic status and number of ICD-9 diagnoses during the exposure period).

Results

The analytic sample consisted of 80 187 individuals (1132 cases, 79 055 controls), with 822 unique ICD-9 codes recorded in their mothers. After extensive quality control, 22 maternal diagnoses were nominally significantly associated with offspring ASD, with 16 of those surviving subsequent filtering steps (permutation testing, multiple testing correction, multiple regression). Among those, we recorded an increased risk of ASD associated with metabolic [e.g. hypertension; HR = 2.74 (1.92–3.90),p= 2.43 × 10−8], genitourinary [e.g. non-inflammatory disorders of cervix; HR = 1.88 (1.38–2.57),p= 7.06 × 10−5] and psychiatric [depressive disorder; HR = 2.11 (1.32–3.35),p= 1.70 × 10−3] diagnoses. Meanwhile, mothers of children with ASD were less likely to attend prenatal care appointment [HR = 0.62 (0.54–0.71),p= 1.80 × 10−11].

Conclusions

Sixteen maternal diagnoses were associated with ASD in the offspring, after rigorous filtering of potential false-positive associations. Replication in other cohorts and further research to understand the mechanisms underlying the observed associations with ASD are warranted.
Compressed pseudo-SLAM: pseudorange-integrated compressed simultaneous localisation and mapping for unmanned aerial vehicle navigation
Authors: Kim Jonghyuk , Guivant Jose , Sollie Martin L. , Bryne Torleiv H. , Johansen Tor Arne
Published: March 2021

This paper addresses the fusion of the pseudorange/pseudorange rate observations from the global navigation satellite system and the inertial–visual simultaneous localisation and mapping (SLAM) to achieve reliable navigation of unmanned aerial vehicles. This work extends the previous work on a simulation-based study [Kim et al. (2017). Compressed fusion of GNSS and inertial navigation with simultaneous localisation and mapping. IEEE Aerospace and Electronic Systems Magazine, 32(8), 22–36] to a real-flight dataset collected from a fixed-wing unmanned aerial vehicle platform. The dataset consists of measurements from visual landmarks, an inertial measurement unit, and pseudorange and pseudorange rates. We propose a novel all-source navigation filter, termed a compressed pseudo-SLAM, which can seamlessly integrate all available information in a computationally efficient way. In this framework, a local map is dynamically defined around the vehicle, updating the vehicle and local landmark states within the region. A global map includes the rest of the landmarks and is updated at a much lower rate by accumulating (or compressing) the local-to-global correlation information within the filter. It will show that the horizontal navigation error is effectively constrained with one satellite vehicle and one landmark observation. The computational cost will be analysed, demonstrating the efficiency of the method.
SARS-CoV-2 re-infection: development of an epidemiological definition from India
Authors: Mukherjee Aparna , Anand Tanu , Agarwal Anup , Singh Harpreet , Chatterjee Pranab , Narayan Jitendra , Rana Salaj , Gupta Nivedita , Bhargava Balram , Panda Samiran
Published: March 2021

The current investigation was conducted with the objective to develop an epidemiological case definition of possible severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) re-infection and assess its magnitude in India. The epidemiological case definition for SARS-CoV-2 re-infection was developed from literature review of data on viral kinetics. For achieving second objective, the individuals who satisfied the developed case definition for SARS-CoV-2 re-infection were contacted telephonically. Taking available evidence into consideration, re-infection with SARS-CoV-2 in our study was defined as any individual who tested positive for SARS-CoV-2 on two separate occasions by either molecular tests or rapid antigen test at an interval of at least 102 days with one negative molecular test in between. In this archive based, telephonic survey, 58 out of 1300 individuals (4.5%) fulfilled the above-mentioned definition; 38 individuals could be contacted with healthcare workers (HCWs) accounting for 31.6% of the cases. A large proportion of participants was asymptomatic and had higher Ct value during the first episode. While SARS-CoV-2 re-infection is still a rare phenomenon, there is a need for epidemiological definition of re-infection for establishing surveillance systems and this study contributes to such a goal.

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) re-infection is an emerging concern and there is a need to define it. Therefore, working epidemiological case definition for re-infection was developed and its magnitude was explored via archive-based, telephonic survey. Re-infection with SARS-CoV-2 was defined as two positive tests at an interval of at least 102 days with one interim negative test. Thirty-eight of the 58 eligible patients could be contacted with 12 (31.6%) being HCWs. Majority of the participants were asymptomatic and had higher Ct value during their first episode. To conclude, a working epidemiological case definition of SARS-CoV-2 re-infection is important to strengthen surveillance. The present investigation contributes to this goal and records reinfection in 4.5% of SARS-CoV-2 infected individuals in India.
Twin Study of the Relationship between Childhood Negative Emotionality and Hyperactivity/Inattention Problems
Authors: Hur Yoon-Mi , Jeong Hoe-Uk
Published: March 2021

The present study aimed to determine the genetic and environmental etiology of the association between childhood negative emotionality (NE) and hyperactivity/inattention problems (HIP) using South Korean elementary school twins (mean age = 10.19 years, SD = 1.79 years). Telephone interviews were given to mothers of 919 twins (229 monozygotic males: 112 pairs and 5 individuals; 148 dizygotic males: 73 pairs and 2 individuals; 180 monozygotic females: 87 pairs and 6 individuals; 103 dizygotic females: 50 pairs and 3 individuals; 259 opposite-sex dizygotic twins: 127 pairs and 5 individuals) to assess their children’s NE and HIP. Consistent with prior studies, the phenotypic correlation between NE and the HIP was moderate (r = .29; 95% CI = .24, .34). Model-fitting analysis revealed that additive genetic and nonshared environmental influences on NE were .45 (95% CI [.34, .54]) and .55 (95% CI [.46, .66]), respectively, and that additive and nonadditive genetic, and nonshared environmental influences on HIP were .08 (95% CI [.03, .26]), .41 (95% CI [.21, .51]) and .51 (95% CI = .42, .61), respectively. In addition, the additive genetic correlation between NE and HIP was 1.0 (95% CI [.52, 1.00]), indicating that additive genetic factors are entirely shared between the two phenotypes. Nonadditive genetic influences were unique to HIP and not responsible for the NE-HIP association. Nonshared environmental correlation was significant but modest (re = .18, 95% CI [.06, .30]).
Are Multi‐Decadal Fluctuations in Arctic and Antarctic Surface Temperatures a Forced Response to Anthropogenic Emissions or Part of Internal Climate Variability?
Authors: England Mark R.
Published: March 2021

In this study, we investigate the drivers of observed multi‐decadal fluctuations in Arctic and Antarctic surface temperatures using multiple large ensembles of climate simulations and single‐forcing ensembles. We find that the observed oscillation in Arctic surface temperature around a linear trend since 1920 is a forced response to emissions of anthropogenic aerosols and greenhouse gases. In contrast, we show that observed multi‐decadal Antarctic surface temperature fluctuations are partially related to Pacific decadal variability which influences the climate of West Antarctica. Lastly, we demonstrate that internally driven multi‐decadal fluctuations at the two poles are not systematically correlated in any climate model examined here, as had been previously suggested. We conclude by discussing the implications of these results for understanding projections of Arctic and Antarctic surface climate of the coming decades.
The Critical Role of Fluid‐Mediated Diffusion in Anomalous Fe‐Mg‐O Isotope Fractionations in Ultramafic Rocks of Ophiolites
Authors: Su Ben‐Xun , Chen Chen , Xiao Yan , Robinson Paul T. , Liu Xia , Wang Jing , Uysal Ibrahim , Bai Yang , Sun Yang
Published: March 2021

A number of bulk‐rock and mineral Fe and Mg isotope data have been increasingly reported from ophiolitic rocks, but their anomalous fractionations are still not well addressed. This study presents new Fe, Mg, and O isotopes and published Li isotope data of olivine and/or chromite in chromitite, dunite, and harzburgite from the Pozantı‐Karsantı ophiolite (southern Turkey) to reveal the mechanisms of inter‐ and intra‐mineral isotope fractionation during chromitite formation. In the studied samples, both olivine and chromite have highly variable δ56Fe ranging from −0.125‰ to 0.101‰ and −0.261‰ to 0.191‰, respectively, but with heavier olivine than coexisting chromite in most samples. In contrast, olivine records homogeneous Mg isotopic compositions with δ26Mg values of −0.36‰ to −0.26‰, whereas chromite grains have variable but relatively high δ26Mg values ranging from −0.02‰ to 0.45‰. The δ18O values of olivine range from 4.65‰ to 5.86‰ and co‐vary with δ7Li (−5.43‰ to 16.65‰), δ56Fe, and δ26Mg, particularly at lithological scale. These isotopic features cannot be explained solely by subsolidus diffusion between olivine and chromite, or by partial melting and fractional crystallization. Instead, they require fluids as a diffusive medium for high efficient element exchange between chromite and olivine. The fluids were likely the hydrous fluids that were collected on chromite grain surfaces during crystallization and released later from chromite piles during precipitation. The fluid‐olivine reaction preferentially transferred light Fe from olivine grains resulting in elevated δ56Fe, but caused small O and Mg isotopic variations in the olivine. The Li diffusion depends on Li concentration gradient between olivine and fluid and olivine/fluid ratio, which can account for large δ7Li variations in olivine between different rock types. As these reactions proceeded, they induced elemental and isotopic variations in the fluids. These fluids could continuously penetrate the harzburgites through the dunite envelopes around the chromitites, producing some of the observed anomalous geochemical features of the harzburgites. Thus, we conclude that the hydrous fluids acted as critical media for ion exchange between chromite and olivine and for significant modification of the host harzburgites.
Theoretical Predictions Versus Environmental Observations on Serpentinization Fluids: Lessons From the Samail Ophiolite in Oman
Authors: Leong J. A. M. , Howells A. E. , Robinson K. J. , Cox A. , Debes R. V. , Fecteau K. , Prapaipong P. , Shock E. L.
Published: March 2021

Thermodynamic calculations provide valuable insights into the reactions that drive the profound fluid transformations during serpentinization, where surface fluids are transformed into some of the most reduced and alkaline fluids on Earth. However, environmental observations usually deviate from thermodynamic predictions, especially those occurring at low temperatures where equilibrium is slowly reached. In this work, we analyzed 138 low‐temperature (<40°C) fluids from the Samail ophiolite in Oman to test thermodynamic predictions with environmental observations. Four fluid types were identified through this work. (i) Type 1 circumneutral (pH 7–9) fluids result from fluid interactions with serpentinized rocks common in the shallow subsurface. (ii) Fluids with pH ranging from 9 to 11 and low Si concentrations are products of intermediate stages of serpentinization. (iii) Type 2 hyperalkaline (pH > 11) fluids approach equilibrium with diopside, and with serpentine and brucite actively forming during advanced stages of serpentinization. Lastly, (iv) most fluids sampled in this work deviate from predicted equilibrium compositions and depict various degrees of mixing between Type 1 and 2 fluids. Mixed fluids fall within the same pH range but have considerably higher dissolved Si than intermediate‐type fluids. Hyperalkaline fluids exhibit variable degrees of mixing despite maintaining pH > 11, implying strong buffering capacity of serpentinization‐generated fluids. Overall, this work demonstrates that predicted and measured compositions of serpentinization‐derived fluids can be reconciled using a combination of equilibrium and fluid‐transport simulations. This work substantiates these calculations as useful tools in exploring serpentinization reactions in continents and perhaps in other low‐temperature environments on Earth and beyond.
Dynamics of Electron Flux in the Slot Region and Geomagnetic Activity
Authors: Nikitina L. , Trichtchenko L.
Published: March 2021

The slot region between the radiation belts in the magnetosphere is statistically less populated by the energetic electrons, which makes it attractive in the design considerations of the satellite missions. As has been shown in the last decades, the dynamics of this region is complicated, with strong enhancements of electron density associated with space weather events. This paper provides an analysis of the dynamics of electron flux in 1998–2007 with specific attention to slot filling events and preceding geomagnetic activity. Flux of energetic electrons, with energies E > 0.63 MeV, E > 1.5 MeV, and E > 3 MeV, was obtained from detectors on board the HEO‐3 satellite in highly elliptical orbit. To evaluate geomagnetic conditions, associated with enhancement of electron flux, all the “slot filling events” were studied together with geomagnetic activity provided by Dst and Kp global indices as well as with the hourly range indices of geomagnetic variations at mid‐latitude. These geomagnetic indices were used for assessment of a threshold and frequency of occurrence of slot filling events. Regression analysis has been used to find a relationship between the maximum filling of the slot region due to space weather event and the preceding geomagnetic activity level. Influence of the cumulative time of periods of enhanced geomagnetic activity to the variation of the electron flux in the slot region has been analyzed. Suitability of different indices of geomagnetic activity for estimation of the rate of occurrence of slot filling events and for assessment of electron flux in the slot region is discussed.