bluuebunny/crossref_metadata_2025_split huggingface dataset:
Value and benefits of model‐based systems engineering (MBSE): Evidence from the literature
Authors: Henderson Kaitlin , Salado Alejandro 
Published: December 2020

AbstractTraditional document‐based practices in systems engineering are being transitioned to model‐based ones. Adoption of model‐based systems engineering (MBSE) continues to grow in industry and government, and MBSE continues to be a major research theme in the systems engineering community. In fact, MBSE remains a central element in the International Council on Systems Engineering (INCOSE)’s vision for 2025. Examining systems engineering literature, this paper presents an assessment of the extent to which benefits and value of MBSE are supported by empirical evidence. A systematic review of research and practice papers in major systems engineering archival journals and conference proceedings was conducted. Evidence was categorized in four types, two of which inductively emerged from the results: measured, observed (without a formal measurement process), perceived (claimed without evidence), and backed by other references. Results indicate that two thirds of claimed MBSE benefits are only supported by perceived evidence, while only two papers reported measured evidence. The aggregate assessment presented in this paper indicates that claims about the value and benefits of MBSE are mainly based on expectation. We argue that evidence supporting the value and benefits of MBSE remains inconclusive.
Phylogenomics of the tropical plant family Ochnaceae using targeted enrichment of nuclear genes and 250+ taxa
Authors: Schneider Julio V. , Jungcurt Tanja , Cardoso Domingos , Amorim André Márcio , Töpel Mats , Andermann Tobias , Poncy Odile , Berberich Thomas , Zizka Georg 
Published: December 2020

AbstractTargeted capture of nuclear genes increasingly contributes to unravelling phylogenetic relationships that hitherto remained unresolved because of limitations of traditional Sanger sequencing. In particular, the study of tropical plant families has been compromised because they often rely on highly degraded DNA obtained from herbarium specimens. One such example is the pantropical Ochnaceae, which comprises 33 genera and approximately 550 species, occurring mostly in savannas and moist tropical forests. Here, we developed a set of baits covering about 660,000 bp from 275 nuclear genes used for the targeted enrichment based on all but one genus and more than 250 species. Using this novel dataset, we resolved the phylogenetic backbone of Ochnaceae, including that of Ochninae, and we established new relationships. Most importantly, our findings highlight that the neotropical and palaeotropical taxa of Sauvagesia form independent clades, requiring the re‐erection of formerly separate genera. Ouratea and Ochna (both Ochninae), by far the most species‐rich genera and represented by 120 and 41 species, respectively, came out as monophyletic. In contrast, the third‐most species‐rich genus, Campylospermum, is polyphyletic in two distinct clades. Ouratea, the only neotropical genus of Ochninae, was sister to the five palaeotropical genera of this subtribe. The bait kit developed in this study proved to be particularly useful for unravelling relationships within Ochninae, which includes about two‐thirds of the species diversity in the family.
Biogeography of succulent spurges from Brazilian Seasonally Dry Tropical Forest (SDTF)
Authors: Hurbath Fernanda , Stubbs Rebecca L. , Cordeiro Inês , Cellinese Nico 
Published: December 2020

AbstractSeasonally Dry Tropical Forests (SDTFs) are found scattered throughout the Neotropics, from northwestern Mexico to northern Argentina, and southwestern and eastern Brazil, with eastern Brazil having the largest and most isolated fragment of SDTF, known as Caatinga. Growing knowledge from dated phylogenies and ancestral reconstruction studies suggests that SDTF lineages are nested in geographically structured phylogenies with clades highly restricted to each disjunct patch. To address these hypotheses, we investigated the biogeographic history of Euphorbia sect. Brasilienses, a group of succulent spurges from eastern Brazil's SDTF. To this aim, we assembled a concatenated matrix from 126 accessions with four markers (302 sequences from previous studies and 19 newly generated): one nuclear (ITS1) and three plastid (matK, ndhF, trnL‐trnF) loci. Our results showed that clade Brasilienses and its sister group Stachydium diverged from a common ancestor during the Miocene around 16.5 Ma. Clade Stachydium was recovered with a mean crown age of 7.7 Ma, while clade Brasilienses was recovered as a relatively young group that started diversifying about 3.1 Ma. Biogeographic results showed that the ancestral range of the clade Stachydium + Brasilienses comprised the Andes and eastern Brazil's SDTF, therefore suggesting past connections between western and eastern South America. The ancestral range of clade Brasilienses was restricted to eastern Brazil SDTF, which contrasts with clade Stachydium, which was recovered with a broader ancestral range around Late Miocene. Our results suggest limited dispersal abilities, niche conservatisms and an origin for E. sect. Brasilienses pre‐dating the Pleistocene. By contributing to the understanding of the origin and diversification of this group of endemic spurges, our study provides insights into the history of this SDTF in eastern South America.
6,8‐Diprenylorobol induces apoptosis in human colon cancer cells via activation of intracellular reactive oxygen species and p53
Authors: Choi Yong Jun , Lee Jongsung , Ha Sang Hoon , Lee Han Ki , Lim Heui Min , Yu Seon‐Hak , Lee Chang Min , Nam Myeong Jin , Yang Yung‐Hun , Park Kyungmoon , Choi Youn Soo , Jang Kyu Yun , Park See‐Hyoung 
Published: December 2020

Abstract6,8‐Diprenylorobol is a natural compound mainly found in Glycyrrhiza uralensis fisch and Maclura tricuspidata, which has been used traditionally as food and medicine in Asia. So far, the antiproliferative effect of 6,8‐diprenylorobol has not been studied yet in colon cancer. In this study, we aimed to evaluate the antiproliferative effects of 6,8‐diprenylorobol in LoVo and HCT15, two kinds of human colon cancer cells. 6,8‐Diprenylorobol inhibited the proliferation of LoVo and HCT15 cells in a dose‐ and time‐dependent manner. A 40 μM of 6,8‐diprenylorobol for 72 h reduced both of cell viability under 50%. After treatment of 6,8‐diprenylorobol (40 and 60 μM) for 72 h, late apoptotic cell portion in LoVo and HCT15 cells were 24, 70% and 13, 90%, respectively, which was confirmed by checking DNA fragmentation in both cells. Mechanistically, 6,8‐diprenylorobol activated p53 and its phosphorylated form (Ser15, Ser20, and Ser46) expression but suppressed Akt and mitogen‐activated protein kinases (MAPKs) phosphorylation in LoVo and HCT15 cells. Interestingly, 6,8‐diprenylorobol induced the generation of intracellular reactive oxygen species (ROS), which was attenuated with N‐acetyl cysteine (NAC) treatment. Compared to the control, 60 μM of 6,8‐diprenylorobol caused to increase ROS level to 210% in LoVo and HCT15, which was reduced into 161% and 124%, respectively with NAC. Furthermore, cell viability and apoptotic cell portion by 6,8‐diprenylorobol was recovered by incubation with NAC. Taken together, these results indicate that 6,8‐diprenylorobol has the potential antiproliferative effect against LoVo and HCT15 colon cancer cells through activation of p53 and generation of ROS.
Revisiting global trends in freshwater insect biodiversity: A reply
Authors: van Klink Roel , Bowler Diana E. , Gongalsky Konstantin B. , Chase Jonathan M. 
Published: December 2020

AbstractJähnig et al. make some useful points regarding the conclusions that can be drawn from our meta‐analysis; however, some issues require clarification. First, we never suggested that there was a globally increasing trend of freshwater insect abundances, but only spoke of an average increasing trend in the available data. We also did not suggest that freshwater quality has improved globally, but rather that documented improvements in water quality can explain at least some of the trends we observed. Second, as we acknowledged, our data are not a representative set of freshwater ecosystems around the world, but they are what is currently accessible. Third, there is indeed no doubt that changes in abundance or biomass need not correlate with changes in other aspects of biodiversity, such as species richness or functional composition. Our analysis was specifically focused on trends in community abundance/biomass because it has been the subject of recent study and speculation, and is a widely available metric in long‐term studies. To better understand the recent changes in freshwater insect assemblages, we encourage freshwater ecologists to further open their troves of data from countless long‐term monitoring schemes so that larger and more comprehensive syntheses can be undertaken.This article is categorized under:
Water and Life > Conservation, Management, and Awareness
Revisiting global trends in freshwater insect biodiversity
Authors: Jähnig Sonja C. , Baranov Viktor , Altermatt Florian , Cranston Peter , Friedrichs‐Manthey Martin , Geist Juergen , He Fengzhi , Heino Jani , Hering Daniel , Hölker Franz , Jourdan Jonas , Kalinkat Gregor , Kiesel Jens , Leese Florian , Maasri Alain , Monaghan Michael T. , Schäfer Ralf B. , Tockner Klement , Tonkin Jonathan D. , Domisch Sami 
Published: December 2020

AbstractA recent global meta‐analysis reported a decrease in terrestrial but increase in freshwater insect abundance and biomass (van Klink et al., Science 368, p. 417). The authors suggested that water quality has been improving, thereby challenging recent reports documenting drastic global declines in freshwater biodiversity. We raise two major concerns with the meta‐analysis and suggest that these account for the discrepancy with the declines reported elsewhere. First, total abundance and biomass alone are poor indicators of the status of freshwater insect assemblages, and the observed differences may well have been driven by the replacement of sensitive species with tolerant ones. Second, many of the datasets poorly represent global trends and reflect responses to local conditions or nonrandom site selection. We conclude that the results of the meta‐analysis should not be considered indicative of an overall improvement in the condition of freshwater ecosystems.This article is categorized under:
Water and Life > Conservation, Management, and Awareness
Contesting the Neoliberal Discourse of the World Class University: ‘Digital Socialism’, Openness and Academic Publishing
Authors: Peters Michael A. , Besley Tina 
Published: December 2020

AbstractThe principal aim of this paper is to contest the neoliberal discourse of the World Class University (WCU). The first section provides an understanding of the concept of the WCU within the context of a global competitive model of the knowledge economy and contrasts it with the social-democratic model based on open science and education that also provides links between new modes of openness, academic publishing and the world journal architecture. The paper makes the case for ‘knowledge socialism’ that accurately depicts the greater communitarian moment of the sharing and participative academic economy based on peer-to-peer production, social innovation and collective intelligence. It instantiates the notion of knowledge as a global public good. Profound changes in the nature of technology has enabled a kind of ‘digital socialism’ which is clearly evident in the shift in political economy of academic publishing based Open Access, cOAlition S, and ‘Plan S’ (mandated in 2020) established by national research funding organisations in Europe with the support of the European Commission and the European Research Council (ERC). The social democratic alternative to neoliberalism and the WCU is a form of the sharing academic economy known as ‘knowledge socialism’. Universities need to share knowledge in the search for effective responses to pressing world problems of fragile global ecologies and the growing significance of technological unemployment. This is a model that proceeds from a very different set of economic and moral assumptions than the neoliberal knowledge economy and the WCU.
Deciphering the genetic and epidemiological landscape of mitochondrial DNA abundance
Authors: Hägg Sara , Jylhävä Juulia , Wang Yunzhang , Czene Kamila , Grassmann Felix 
Published: December 2020

AbstractMitochondrial (MT) dysfunction is a hallmark of aging and has been associated with most aging-related diseases as well as immunological processes. However, little is known about aging, lifestyle and genetic factors influencing mitochondrial DNA (mtDNA) abundance. In this study, mtDNA abundance was estimated from the weighted intensities of probes mapping to the MT genome in 295,150 participants from the UK Biobank. We found that the abundance of mtDNA was significantly elevated in women compared to men, was negatively correlated with advanced age, higher smoking exposure, greater body-mass index, higher frailty index as well as elevated red and white blood cell count and lower mortality. In addition, several biochemistry markers in blood-related to cholesterol metabolism, ion homeostasis and kidney function were found to be significantly associated with mtDNA abundance. By performing a genome-wide association study, we identified 50 independent regions genome-wide significantly associated with mtDNA abundance which harbour multiple genes involved in the immune system, cancer as well as mitochondrial function. Using mixed effects models, we estimated the SNP-heritability of mtDNA abundance to be around 8%. To investigate the consequence of altered mtDNA abundance, we performed a phenome-wide association study and found that mtDNA abundance is involved in risk for leukaemia, hematologic diseases as well as hypertension. Thus, estimating mtDNA abundance from genotyping arrays has the potential to provide novel insights into age- and disease-relevant processes, particularly those related to immunity and established mitochondrial functions.
Critically Charged Superfluid 4He Surface in Inhomogeneous Electric Fields
Authors: Möller Th. B. , Moroshkin P. , Kono K. , Scheer E. , Leiderer P. 
Published: December 2020

AbstractWe have studied the spatial distribution of charges trapped at the surface of superfluid helium in the inhomogeneous electric field of a metallic tip close to the liquid surface. The electrostatic pressure of the charges generates a deformation of the liquid surface, leading to a “hillock” (called “Taylor cone”) or “dimple”, depending on whether the tip is placed above or below the surface. We use finite element simulations for calculating the surface profile and the corresponding charge density in the vicinity of the tip. Typical electric fields E are in the range of a few kV/cm, the maximum equilibrium surface deformations have a height on the order of (but somewhat smaller than) the capillary length of liquid 4He (0.5 mm), and the maximum number density of elementary charges in a hillock or dimple, limited by an electrohydrodynamic instability, is some 1013 m−2. These results can be used to determine the charge density at a liquid helium surface from the measured surface profile. They also imply that inhomogeneous electric fields at a bulk helium surface do not allow one to increase the electron density substantially beyond the limit for a homogeneous field, and are therefore not feasible for reaching a density regime where surface state electrons are expected to show deviations from the classical behavior. Some alternative solutions are discussed.
Fleeting Agencies
Authors: Datta Arunima 
Published: December 2020

Fleeting Agencies disrupts the male-dominated narratives by focusing on gendered patterns of migration and showing how South Asian women labour migrants engaged with the process of migration, interacted with other migrants and negotiated colonial laws. This is the first study of Indian coolie women in British Malaya to date. In exploring the politicization of labour migration trends and gender relations in the colonial plantation society in British Malaya, the author foregrounds how the migrant Indian 'coolie' women manipulated colonial legal and administrative perceptions of Indian women; their gender-prescriptive roles, relations within patriarchal marriage institutions, and even the emerging Indian national independence movement in India and Malaya. All this, to ensure their survival, escape from unfavourable relations and situations, and improve their lives. The book also introduces the concept of situational or fleeting agency, which contributes to further a nuanced understanding of agency in the lives of Indian coolie women.
Local and Nonlocal Impacts of Gaps on Submerged Canopy Flow
Authors: Chung Hayoon , Mandel Tracy , Zarama Francisco , Koseff Jeffrey R. 
Published: December 2020

AbstractAlthough shear layers generated by submerged vegetation reach a steady state once production and dissipation are balanced within a canopy, shear layers found in gaps and after trailing edges of canopy patches are inherently different and thereby perturb the canopy's mean and turbulent fields. Experiments were conducted in a laboratory flume to study canopy systems in which two model patches of submerged, rigid cylinder arrays are interrupted by a gap of varying stream‐wise lengths. Results show that, consistent with past studies, gaps locally enhance turbulence. However, this perturbation does not remain “local” within the gap, instead introducing enhanced turbulent energies throughout the water column that are transported downstream and thereby perturb the canopy flow. The study suggests a scaling, , which compares the eddy turnover time of the turbulence produced by the gap to the advection time downstream the second patch, that can be used to predict if turbulence perturbations induced by an upstream gap will influence the turbulence at a given distance downstream.
Near‐infrared Spectra of Lunar Ferrous Mineral Mixtures
Authors: Zhang Xunyu , Cloutis Edward 
Published: December 2020

AbstractIron‐bearing minerals are a major component of materials on the lunar surface, and many of them can be distinguished based on the diagnostic absorption features in visible and near‐infrared reflectance spectra. The relationship between the 1 µm absorption (Band I) center and the band area ratio (BAR), defined as the ratio of 2–1 µm absorption areas, provides a sensitive way to estimate the relative abundance of olivine (Ol) and pyroxene. In the plot of the BAR value versus the Band I center, the Ol‐orthopyroxene (Opx) mixing line (derived from terrestrial materials) is strictly applicable only to Ol‐Opx mixtures. Based on published database of laboratory spectra and compositional data for lunar rocks and mineral separates, this study investigated the spectral characteristics of a variety of common Fe2+‐bearing lunar minerals and rocks, such as clinopyroxene (Cpx), ilmenite‐rich basalt, pyroxene‐bearing anorthosite, and glass‐rich impact melt. The lunar Ol‐Cpx‐Opx mixing line for rocks and minerals is determined, which contains less curvature than the Ol‐Opx mixing line, consistent with both the higher Fe2+ content of lunar mafic silicates and the presence of appreciable Cpx. This study suggests that some of the pyroxene‐bearing lunar materials that are rich in ilmenite, glass, or plagioclase can also be distinguished by this method. These results indicate that the plot of the BAR value versus the Band I center is a useful tool for spectral analysis of lunar composition and mineralogy, especially for those having pyroxene‐dominated spectra.
Tidal Effects on the Longitudinal Structures of the Martian Thermosphere and Topside Ionosphere Observed by MAVEN
Authors: Fang Xiaohua , Forbes Jeffrey M. , Gan Quan , Liu Guiping , Thaller Scott , Bougher Stephen , Andersson Laila , Benna Mehdi , Eparvier Francis , Ma Yingjuan , Pawlowski David , England Scott , Jakosky Bruce 
Published: December 2020

AbstractLongitudinal structures in the Martian thermosphere and topside ionosphere between 150 and 200 km altitudes are studied using in situ electron and neutral measurements from the NASA Mars Atmosphere and Volatile EvolutioN (MAVEN) mission. Four time intervals are selected for comparison, during which MAVEN sampled similar local time (9.3–10.3 h) and latitude (near 20°S) regions but at different solar longitude positions (two near northern summer solstice, one each at northern vernal and autumnal equinoxes). Persistent and pronounced tidal oscillations characterize the ionosphere and thermosphere, whose longitudinal variations in density are generally in‐phase with each other. Our analysis of simultaneous and collocated neutral and electron data provides direct observational evidence for thermosphere‐ionosphere coupling through atmospheric tides. We conclude that the ionosphere is subject to modulation by upward‐propagating thermal tides, via both tide‐induced vertical displacement and photochemical reactions. Atmospheric tides constitute a ubiquitous and significant perturbation source to the ionospheric electron density, up to ∼15% near 200 km.
P‐wave Tomography and Azimuthal Anisotropy of the Manila‐Taiwan‐Southern Ryukyu Region
Authors: Fan Jianke , Zhao Dapeng 
Published: December 2020

AbstractTaiwan is considered to be created by interactions between the Manila and Ryukyu subduction zones, which form a normal double‐slab subduction system. Because of the two opposite dipping subductions of the Eurasian Plate (EP) and the Philippine Sea Plate (PSP) around Taiwan, subduction polarity reversal beneath northern Taiwan is presumed, which is accounted for by a slab breakoff model. However, this model has not been convincingly supported by tomographic results so far. Moreover, details of the dynamic process and deformation in this normal double‐slab subduction system are still unclear. In this work, we determine high‐resolution 3‐D tomographic images of isotropic P‐wave velocity and azimuthal anisotropy beneath the Manila‐Taiwan‐southern Ryukyu region, which provide substantial observational constraints on this double‐slab subduction system. Our results clearly show the subducted EP breakoff beneath northern Taiwan. We propose two possible factors causing the slab breakoff: the subducted EP rollback under its own gravity after its subduction cessation and collision with the subducted PSP, which may jointly cause the slab breakoff beneath northern Taiwan after a longer collision history. In addition, the subducted EP rollback may be responsible for magmatism and basalts around Taiwan, as well as recent big earthquakes beneath the Taiwan Strait and the South China Sea (SCS). Our results also reveal anisotropy parallel with the SCS fossil ridge beneath the northernmost Luzon Island. We suggest that the fossil ridge and buoyant plateau subduction and/or the ridge‐parallel mantle flow during the SCS seafloor spreading may result in the ridge‐parallel anisotropy.
TW-SIR: time-window based SIR for COVID-19 forecasts
Authors: Liao Zhifang , Lan Peng , Liao Zhining , Zhang Yan , Liu Shengzong 
Published: December 2020

AbstractSince the outbreak of COVID-19, many COVID-19 research studies have proposed different models for predicting the trend of COVID-19. Among them, the prediction model based on mathematical epidemiology (SIR) is the most widely used, but most of these models are adapted in special situations based on various assumptions. In this study, a general adapted time-window based SIR prediction model is proposed, which is characterized by introducing a time window mechanism for dynamic data analysis and using machine learning method predicts the basic reproduction number and the exponential growth rate of the epidemic. We analyzed COVID-19 data from February to July 2020 in seven countries–––China, South Korea, Italy, Spain, Brazil, Germany and France, and the numerical results showed that the framework can effectively measure the real-time changes of the parameters during the epidemic, and error rate of predicting the number of COVID-19 infections in a single day is within 5%.