bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of the glial cytoarchitecture of the developing olfactory bulb of a shark using immunochemical markers of radial glia
Authors: Docampo-Seara A. , Candal E. , Rodríguez M. A.
Published: January 2022

During development of the olfactory bulb (OB), glial cells play key roles in axonal guiding/targeting, glomerular formation and synaptic plasticity. Studies in mammals have shown that radial glial cells and peripheral olfactory glia (olfactory ensheathing cells, OECs) are involved in the development of the OB. Most studies about the OB glia were carried out in mammals, but data are lacking in most non-mammalian vertebrates. In the present work, we studied the development of the OB glial system in the cartilaginous fish Scyliorhinus canicula (catshark) using antibodies against glial markers, such as glial fibrillary acidic protein (GFAP), brain lipid-binding protein (BLBP), and glutamine synthase (GS). These glial markers were expressed in cells with radial morphology lining the OB ventricle of embryos and this expression continues in ependymal cells (tanycytes) in early juveniles. Astrocyte-like cells were also observed in the granular layer and surrounding glomeruli. Numerous GS-positive cells were present in the primary olfactory pathway of embryos. In the developmental stages analysed, the olfactory nerve layer and the glomerular layer were the regions with higher GFAP, BLBP and GS immuno-reactivity. In addition, numerous BLBP-expressing cells (a marker of mammalian OECs) showing proliferative activity were present in the olfactory nerve layer. Our findings suggest that glial cells of peripheral and central origin coexist in the OB of catshark embryos and early juveniles. These results open the path for future studies about the differential roles of glial cells in the catshark OB during embryonic development and in adulthood.
Metazoan endoparasite fauna and feeding ecology of commercial fishes from Java, Indonesia
Authors: Koepper Svenja , Nuryati Sri , Palm Harry W. , Wild Christian , Yulianto Irfan , Kleinertz Sonja
Published: January 2022

Despite being an important component of the marine ecosystem and posing health risks to human seafood consumers, fish parasites in Indonesia have yet to be adequately described. Here, we analyzed the diet and metazoan parasite fauna of seven commercial fish species (Alectis indica,Carangoides chrysophrys,Johnius borneensis,Mene maculata,Trichiurus lepturus,Upeneus asymmetricus,U. moluccensis) landed in Java, Indonesia. We isolated 11 endoparasite species, established 22 new host and 14 new locality records, and extended parasitological records ofA. indicaby 24%,C. chrysophrysby 25%,J. borneensisby 40%,M. maculataby 44%,U. asymmetricusby 100%, andU. moluccensisby 17%. We genetically identified the trematodeStephanostomumcf.uku(of Bray et al. 2005) fromAlecta indicafor the first time in Indonesia and provided the sequence of its 28S marker. Stomach content analysis revealed seven different prey items, and the examined fish species were grouped into four feeding categories, which differed significantly in their respective endoparasite fauna. All but two examined fish species hosted potentially zoonotic nematodes, which reveal a risk for parasite-borne diseases in Indonesian food fishes and call for more consequent monitoring with regard to seafood safety in this region. With this study, we were able to establish an association between the feeding ecology and the endoparasite fauna of marine fishes which will help to better understand the transmission pathways of (potentially zoonotic) parasites in food fishes in tropical waters.
Genome size variation in Deschampsia cespitosa sensu lato (Poaceae) in Eurasia
Authors: Greimler Josef , Temsch Eva M. , Xue Zhiqing , Weiss-Schneeweiss Hanna , Volkova Polina , Peintinger Markus , Wasowicz Pawel , Shang Hui , Schanzer Ivan , Chiapella Jorge O.
Published: January 2022

The grass Deschampsia cespitosa is a variable taxon out of which many varieties, subspecies and endemic species have been separated. In this paper, the variation in genome size (GS) and ploidy of this grass including several of its subspecies and two related species in Eurasia was investigated by flow cytometric (FCM) measurements. GS and ploidy data were also related to specific environments and reproduction mode. Ploidy levels found by FCM were confirmed by chromosome counts of diploid (2n = 26) and tetraploid (2n = 52) samples. Seminiferous (seed bearing) D. cespitosa was mainly diploid (GS between 3.754 and 5.438 pg/1C). GS variation in diploids showed a geographic pattern with a significant difference (H = 41,441, P < 0.001) between European (median = 4.377 pg) and Asian (median = 4.881 pg) accessions. Genome size (1C) in tetraploids ranged from 7.9426 to 9.0399 pg. Tetraploid seminiferous D. cespitosa was found mostly in disturbed habitats in western and southern Europe, while tetraploids in Asia were registered in wet Arctic habitats. Genome size (1C between 8.3278 and 8.8603 pg) of the pseudoviviparous plants (spikelets produce plantlets asexually) of wet habitats in central and northern Europe indicated tetraploidy. A putative triploid (GS 6.6817 pg) was detected in Iceland. Summing up, we found a high variation in GS on the geographic scale with significant regional differences in diploid D. cespitosa. Among the tetraploids, the asexually reproducing plants were bound to specific habitats, while the seminiferous plants showed a habitat preference similar to the diploids.
On a mixture of an MGT viscous material and an elastic solid
Authors: Fernández José R. , Quintanilla Ramón
Published: January 2022

A lot of attention has been paid recently to the study of mixtures and also to the Moore–Gibson–Thompson (MGT) type equations or systems. In fact, the MGT proposition can be used to describe viscoelastic materials. In this paper, we analyze a problem involving a mixture composed by a MGT viscoelastic type material and an elastic solid. To this end, we first derive the system of equations governing the deformations of such material. We give the suitable assumptions to obtain an existence and uniqueness result. The semigroups theory of linear operators is used. The paper concludes by proving the exponential decay of solutions with the help of a characterization of the exponentially stable semigroups of contractions and introducing an extra assumption. The impossibility of location is also shown.
Non-convex nested Benders decomposition
Authors: Füllner Christian , Rebennack Steffen
Published: January 2022

We propose a new decomposition method to solve multistage non-convex mixed-integer (stochastic) nonlinear programming problems (MINLPs). We call this algorithm non-convex nested Benders decomposition (NC-NBD). NC-NBD is based on solving dynamically improved mixed-integer linear outer approximations of the MINLP, obtained by piecewise linear relaxations of nonlinear functions. Those MILPs are solved to global optimality using an enhancement of nested Benders decomposition, in which regularization, dynamically refined binary approximations of the state variables and Lagrangian cut techniques are combined to generate Lipschitz continuous non-convex approximations of the value functions. Those approximations are then used to decide whether the approximating MILP has to be dynamically refined and in order to compute feasible solutions for the original MINLP. We prove that NC-NBD converges to an $$\varepsilon $$
ε
-optimal solution in a finite number of steps. We provide promising computational results for some unit commitment problems of moderate size.
Effect of oxygen on the germination and culturability of Bacillus atrophaeus spores
Authors: Wu Wen Jie , Chang Jinhui
Published: January 2022

The effect of oxygen on the germination and culturability of aerobic Bacillus atrophaeus spores was investigated in this study. Under oxic or anoxic conditions, various nutritional and non-nutritional germinants were utilized to induce germination. Tb3+-dipicolinic acid fluorescence assay and phase-contrast microscopy were used to track the germination process. The final germination level, germination half time, and germination speed were used to define germination kinetics. Colony-forming unit enumeration was used to assess the culturability of germinated spores germinated with or without oxygen. The results show that in the absence of oxygen, the final germination level was unaffected, germination half time decreased by up to 35.0%, germination speed increased by up to 27.4%, and culturability decreased by up to 95.1%. It is suggested that oxygen affects some germinant receptor-dependent germination pathways, implying that biomolecules engaged in these pathways may be oxygen-sensitive. Furthermore, spores that have completed the germination process in either anoxic or oxic conditions may have different culturability. This research contributed to a better understanding of the fundamental mechanism of germination.
Vascular 3D Printing with a Novel Biological Tissue Mimicking Resin for Patient-Specific Procedure Simulations in Interventional Radiology: a Feasibility Study
Authors: Kaufmann R. , Zech C. J. , Takes M. , Brantner P. , Thieringer F. , Deutschmann M. , Hergan K. , Scharinger B. , Hecht S. , Rezar R. , Wernly B. , Meissnitzer M.
Published: January 2022

Three-dimensional (3D) printing of vascular structures is of special interest for procedure simulations in Interventional Radiology, but remains due to the complexity of the vascular system and the lack of biological tissue mimicking 3D printing materials a technical challenge. In this study, the technical feasibility, accuracy, and usability of a recently introduced silicone-like resin were evaluated for endovascular procedure simulations and technically compared to a commonly used standard clear resin. Fifty-four vascular models based on twenty-seven consecutive embolization cases were fabricated from preinterventional CT scans and each model was checked for printing success and accuracy by CT-scanning and digital comparison to its original CT data. Median deltas (Δ) of luminal diameters were 0.35 mm for clear and 0.32 mm for flexible resin (216 measurements in total) with no significant differences (p > 0.05). Printing success was 85.2% for standard clear and 81.5% for the novel flexible resin. In conclusion, vascular 3D printing with silicone-like flexible resin was technically feasible and highly accurate. This is the first and largest consecutive case series of 3D-printed embolizations with a novel biological tissue mimicking material and is a promising next step in patient-specific procedure simulations in Interventional Radiology.
Gender differences in the intention to get vaccinated against COVID-19: a systematic review and meta-analysis
Authors: Zintel Stephanie , Flock Charlotte , Arbogast Anna Lisa , Forster Alice , von Wagner Christian , Sieverding Monika
Published: January 2022

Aim

We conducted a systematic review and meta-analysis to analyse gender differences in COVID-19 vaccination intentions.

Subject and methods

PubMed, Web of Science and PsycInfo were searched (November 2020 to January 2021) for studies reporting absolute frequencies of COVID-19 vaccination intentions by gender. Averaged odds ratios comparing vaccination intentions among men and women were computed. Descriptive analyses of the studies were reported.

Results

Sixty studies were included in the review and data from 46 studies (n = 141,550) were available for meta-analysis. A majority (58%) of papers reported men to have higher intentions to get vaccinated against COVID-19. Meta-analytic calculations showed that significantly fewer women stated that they would get vaccinated than men, OR 1.41 (95% CI 1.28 to 1.55). This effect was evident in several countries, and the difference was bigger in samples of health care workers than in unspecified general population samples.

Conclusion

This systematic review and meta-analysis found lower vaccination intentions among women than men. This difference is discussed in the light of recent data on actual vaccination rates in different countries.
Cardiac involvement in cystic fibrosis evaluated using cardiopulmonary magnetic resonance
Authors: Lagan Jakub , Naish Josephine H. , Bradley Joshua , Fortune Christien , Palmer Charlie , Clark David , Schelbert Erik B. , Schmitt Matthias , Bright-Thomas Rowland , Miller Christopher A.
Published: January 2022

Cystic fibrosis (CF) transmembrane conductance regulator is expressed in myocardium, but cardiac involvement in CF remains poorly understood. The recent development of a combined cardiopulmonary magnetic resonance imaging technology allows for a simultaneous interrogation of cardiac and pulmonary structure and function. The aim of this study was to investigate myocardial manifestations in adults with CF, both in a stable state and during an acute respiratory exacerbation, and to investigate the relationship between cardiac and pulmonary disease. Healthy adult volunteers (n = 12) and adults with CF (n = 10) were studied using a multiparametric cardiopulmonary magnetic resonance protocol. CF patients were scanned during an acute respiratory exacerbation and re-scanned when stable. Stable CF was associated with left ventricular dilatation and hypertrophy (LVH; left ventricular mass: CF 59 ± 9 g/m2 vs. control 50 ± 8 g/m2; p = 0.028). LVH was predominantly driven by extracellular myocardial matrix expansion (extracellular matrix mass: CF 27.5 ± 3.4 g vs. control 23.6 ± 5.2 g; p = 0.006; extracellular volume [ECV]: CF 27.6 [24.7–29.8]% vs. control 24.8 [22.9–26.0]%; p = 0.030). Acute CF was associated with an acute reduction in left ventricular function (ejection fraction: acute 57 ± 3% vs. stable 61 ± 5%; p = 0.025) and there was a suggestion of myocardial oedema. Myocardial oedema severity was strongly associated with the severity of airflow limitation (r = − 0.726, p = 0.017). Multiparametric cardiopulmonary magnetic resonance technology allows for a simultaneous interrogation of cardiac and pulmonary structure and function. Stable CF is associated with adverse myocardial remodelling, including left ventricular systolic dilatation and hypertrophy, driven by myocardial fibrosis. CF exacerbation is associated with acute myocardial contractile dysfunction. There is also a suggestion of myocardial oedema in the acute period which is related to pulmonary disease severity.
Is employer engagement effective in external quality assurance of higher education? A paradigm shift or QA disruption from quality assurance perspectives in Asia
Authors: Hou Angela Yung Chi , Hill Christopher , Justiniano Dewin , Lin Arianna Fang Yu , Tasi Sandy
Published: January 2022

Due to global attention on student employability, employers are expected to be involved in institutional governance in higher education and quality assurance (QA). Due to the difficulties in recruiting motivated employers to participate in external QA governance and process, this has become a challenging issue in many Asian nations. The paper aims to explore employer legitimacy in Asian national higher education regulations and EQA system according to a four-dimensional diagram of institutional governance model. There are two major findings. First, Asian governments developed QA policies with a focus on employer engagement but the emerging practice is still ineffective. Second, approaches of employer engagement in QA governance vary context to context, such as HK and Malaysia in the excellence mode; Taiwan, Indonesia, Australia, New Zealand belong to advanced type; and China, Thailand, and Vietnam fall in the intermediate category.
Development of TiB and nanocrystalline Ti-reinforced novel hybrid Ti nanocomposite produced by powder metallurgy
Authors: Angel D. A. , Mikó T. , Kristály F. , Benke M. , Gácsi Z.
Published: January 2022

Titanium monoboride (TiB) whisker-reinforced titanium (Ti) matrix composites were produced by powder metallurgy, through vacuum sintering. TiB is formed by thermal decomposition of TiB2 precursor. In addition, a new hybrid composite was developed by admixing nanograined and nanocrystalline (more important) Ti to enhance the transformation mechanism of TiB2 to TiB phase. The morphology and particle size of the initial powders, mixtures and the microstructure of the composites have been studied by scanning electron microscopy (SEM). The phase analysis and transformation monitoring were performed by X-ray diffraction (XRD). The sintered composites were also subjected to compressive strength and hardness measurements. According to XRD results, through the addition of nanocrystalline Ti, a probable enhancement of the TiB2 → TiB transformation occurred producing more TiB whiskers in the hybrid composites. All samples of the hybrid composites exhibited improved yield strength (1365 MPa) and hardness (358 HV) compared to the non-hybrid ones 927 MPa and 254 HV, respectively.

Graphical abstract
“We are also here”—Spiritual Care Practitioners’ Experiences of the COVID-19 Pandemic: A Qualitative Study from Poland
Authors: Domaradzki Jan
Published: January 2022

Although healthcare professionals have become the symbol of risk and sacrifice during the COVID-19 pandemic, spiritual care practitioners (SCP) have also put themselves at great risk while offering their service in hospitals, hospices and other healthcare facilities. This study was designed to explore the lived experiences of SCP during the current health crisis in Poland. Semi-structured interviews were conducted with twenty-four SCP. Nine major themes emerged from the interviews: personal reactions to the pandemic, SCP’s perception of the pandemic, the impact of COVID-19 on the provision of spiritual care, spiritual needs during the pandemic, work-related emotions, the impact of the COVID-19 on religion, the role of spiritual care during the outbreak, the healthcare professionals’ perceptions of SCP and barriers to the provision of spiritual care during the pandemic. The SCP indicated that although the COVID-19 crisis has affected the availability of pastoral, religious and spiritual care, it has amplified the importance of such care and has positively influenced the visibility of SCP in modern healthcare practice. Nonetheless, in such desperate times, SCP are still neglected and should be further recognised and integrated into the healthcare system.
Pooling Modalities and Pointwise Intersection: Semantics, Expressivity, and Dynamics
Authors: Van De Putte Frederik , Klein Dominik
Published: January 2022

We study classical modal logics with pooling modalities, i.e. unary modal operators that allow one to express properties of sets obtained by the pointwise intersection of neighbourhoods. We discuss salient properties of these modalities, situate the logics in the broader area of modal logics (with a particular focus on relational semantics), establish key properties concerning their expressive power, discuss dynamic extensions of these logics and provide reduction axioms for the latter.
Complex climate and network effects on internal migration in South Africa revealed by a network model
Authors: Xiao Tingyin , Oppenheimer Michael , He Xiaogang , Mastrorillo Marina
Published: January 2022

Climate variability and climate change influence human migration both directly and indirectly through a variety of channels that are controlled by individual and household socioeconomic, cultural, and psychological processes as well as public policies and network effects. Characterizing and predicting migration flows are thus extremely complex and challenging. Among the quantitative methods available for predicting such flows is the widely used gravity model that ignores the network autocorrelation among flows and thus may lead to biased estimation of the climate effects of interest. In this study, we use a network model, the additive and multiplicative effects model for network (AMEN), to investigate the effects of climate variability, migrant networks, and their interactions on South African internal migration. Our results indicate that prior migrant networks have a significant influence on migration and can modify the association between climate variability and migration flows. We also reveal an otherwise obscure difference in responses to these effects between migrants moving to urban and non-urban destinations. With different metrics, we discover diverse drought effects on these migrants; for example, the negative standardized precipitation index (SPI) with a timescale of 12 months affects the non-urban-oriented migrants’ destination choices more than the rainy season rainfall deficit or soil moisture do. Moreover, we find that socioeconomic factors such as the unemployment rate are more significant to urban-oriented migrants, while some unobserved factors, possibly including the abolition of apartheid policies, appear to be more important to non-urban-oriented migrants.
Long-term assessment of floodplain reconnection as a stream restoration approach for managing nitrogen in ground and surface waters
Authors: Mayer Paul M. , Pennino Michael J. , Newcomer-Johnson Tammy A. , Kaushal Sujay S.
Published: January 2022

Stream restoration is a popular approach for managing nitrogen (N) in degraded, flashy urban streams. Here, we investigated the long-term effects of stream restoration involving floodplain reconnection on riparian and in-stream N transport and transformation in an urban stream in the Chesapeake Bay watershed. We examined relationships between hydrology, chemistry, and biology using a Before/After-Control/Impact (BACI) study design to determine how hydrologic flashiness, nitrate (NO3−) concentrations (mg/L), and N flux, both NO3− and total N (kg/yr), changed after the restoration and floodplain hydrologic reconnection to its stream channel. We examined two independent surface water and groundwater data sets (EPA and USGS) collected from 2002–2012 at our study sites in the Minebank Run watershed. Restoration was completed during 2004 and 2005. Afterward, the monthly hydrologic flashiness index, based on mean monthly discharge, decreased over time from 2002 and 2008. However, from 2008–2012 hydrologic flashiness returned to pre-restoration levels. Based on the EPA data set, NO3− concentration in groundwater and surface water was significantly less after restoration while the control site showed no change. DOC and NO3− were negatively related before and after restoration suggesting C limitation of N transformations. Long-term trends in surface water NO3− concentrations based on USGS surface water data showed downward trends after restoration at both the restored and control sites, whereas specific conductance showed no trend. Comparisons of NO3− concentrations with Cl− concentrations and specific conductance in both ground and surface waters suggested that NO3− reduction after restoration was not due to dilution or load reductions from the watershed. Modeled NO3− flux decreased post restoration over time but the rate of decrease was reduced likely due to failure of restoration features that facilitated N transformations. Groundwater NO3− concentrations varied among stream features suggesting that some engineered features may be functionally better at creating optimal conditions for N retention. However, some engineered features eroded and failed post restoration thereby reducing efficacy of the stream restoration to reduce flashiness and NO3− flux. N management via stream restoration will be most effective where flashiness can be reduced and DOC made available for denitrifiers. Stream restoration may be an important component of holistic watershed management including stormwater management and nutrient source control if stream restoration and floodplain reconnection can be done in a manner to resist the erosive effects of large storm events that can degrade streams to pre-restoration conditions. Long-term evolution of water quality functions in response to degradation of restored stream channels and floodplains from urban stressors and storms over time warrants further study, however.
Comparative assessment on the probable mechanisms underlying the hepatorenal toxicity of commercial imidacloprid and hexaflumuron formulations in rats
Authors: Hassanen Eman I. , Hussien Ahmed M. , Mehanna Sally , Ibrahim Marwa A. , Hassan Neven H.
Published: January 2022

Pesticides are viewed as a major wellspring of ecological contamination and causing serious risky consequences for people and animals. Imidacloprid (IM) and hexaflumuron (HFM) are extensively utilized insect poisons for crop assurance on the planet. A few investigations examined IM harmfulness in rodents, but its exact mechanism hasn’t been mentioned previously as well as the toxicity of HFM doesn’t elucidate yet. For this reason, the present study was designed to explore the mechanism of each IM and HFM–evoked rat liver and kidney toxicity and to understand its molecular mechanism. 21 male Wistar albino rats were divided into 3 groups, as follows: group (1), normal saline; group (2), IM; and group (3), HFM. Both insecticides were orally administered every day for 28 days at a dose equal to 1/10 LD50 from the active ingredient. After 28 days postdosing, rats were anesthetized to collect blood samples then euthanized to collect liver and kidney tissue specimens. The results showed marked changes in walking, body tension, alertness, and head movement with a significant reduction in rats’ body weight in both IM and HFM receiving groups. Significant increases in MDA levels and decrease of GHS levels were recorded in liver and kidney homogenates of either IM or HFM groups. Liver and kidney tissues obtained from both pesticide receiving groups showed extensive histopathological alterations with a significant increase in the serum levels of ALT, AST, urea, and creatinine and a decrease in total proteins, albumin, and globulin levels. In addition, there was upregulation of the transcript levels of casp-3, JNK, and HO-1 genes with strong immunopositivity of casp-3, TNF-ὰ, and NF-KB protein expressions in the liver and kidneys of rats receiving either IM or HFM compared with the control group. In all studied parameters, HFM caused hepatorenal toxicity more than those induced by IM. We can conclude that each IM and HFM provoked liver and kidneys damage through overproduction of ROS, activation of NF-KB signaling pathways and mitochondrial/JNK-dependent apoptosis pathway.
Numerical and experimental investigation of flat-clinch joint strength
Authors: Friedrich Sandra , Gerstmann Thoralf , Binotsch Carolin , Awiszus Birgit
Published: January 2022

The striving for energy savings by lightweight construction requires the combination of different materials with advantageous properties. For joining sheet metal components, clinching offers a good alternative to thermal joining processes. In contrast to thermal joining processes, the microstructure in the joining zone remains largely unaffected. Conventional clinch joints, however, have a protrusion on the underside of the joint, which restricts their use in functional and visible surfaces. Flat-clinching minimizes this disadvantage by using a flat anvil instead of a die. Due to the flatness on the underside, it can be used in visible and functional surfaces. This paper deals with the increase of joint strength by using an auxiliary joining element (AJE) in the second forming stage. To achieve optimum improvement in the joint strength of an aluminum Al99.5 H14 sheet metal joint and to save costs, the AJE was varied numerically in terms of volume, material and basic shape. The geometric parameters (e.g., interlocking f and neck thickness tn) do not allow direct derivation of the joint strength. For this reason, the 2D clinch model was extended for the first time to include 3D load models (cross tension, shear tension). To validate the numerical results, optimized flat-clinch joints with AJE and the associated load tests were implemented experimentally. The numerical models were used to improve the process development.
States and Refugee Integration: a Comparative Analysis of France, Germany, and Switzerland
Authors: Feinstein Scott , Poleacovschi Cristina , Drake Riley , Winters Leslie Ann
Published: January 2022

The Syrian civil war led to mass migration and Europe becoming a potential site of refuge. How have Syrians experienced refuge in Europe? Drawing on 58 interviews with Syrian refugees in Germany, France, and Switzerland, we find that refugees continue to experience exclusion in all integration domains including those found as markers and means, social connections, facilitators, and foundations of integration . While our cases demonstrate that Syrian refugees in Europe experience discrimination across all domains, not all conditions are equal. Using narrative analysis, differences were observed within three integration domains. Accessing language programs was more challenging in France, finding housing was more challenging in Germany, and F type residence permits limited refugees’ rights in Switzerland more than in other countries. Discrimination across domains is deepening the socio-cultural-economic divide between autochthonous communities and Syrian refugees, but not all domains are equally divisive across countries. The findings outline that where these states outsourced refugee services, refugees experienced increased barriers to integration.
Hermitian–Yang–Mills Connections on Collapsing Elliptically Fibered K3 Surfaces
Authors: Datar Ved , Jacob Adam
Published: January 2022

Let$$X\rightarrow {{\mathbb {P}}}^1$$X→P1be an elliptically fiberedK3 surface, admitting a sequence$$\omega _{i}$$ωiof Ricci-flat metrics collapsing the fibers. LetVbe a holomorphicSU(n) bundle overX, stable with respect to$$\omega _i$$ωi. Given the corresponding sequence$$\Xi _i$$Ξiof Hermitian–Yang–Mills connections onV, we prove that, ifEis a generic fiber, the restricted sequence$$\Xi _i|_{E}$$Ξi|Econverges to a flat connection$$A_0$$A0. Furthermore, if the restriction$$V|_E$$V|Eis of the form$$\oplus _{j=1}^n{\mathcal {O}}_E(q_j-0)$$⊕j=1nOE(qj-0)forndistinct points$$q_j\in E$$qj∈E, then these points uniquely determine$$A_0$$A0.
Measuring Impartial Beneficence: A Kantian Perspective on the Oxford Utilitarianism Scale
Authors: Mihailov Emilian
Published: January 2022

To capture genuine utilitarian tendencies, (Kahane et al., Psychological Review 125:131, 2018) developed the Oxford Utilitarianism Scale (OUS) based on two subscales, which measure the commitment to impartial beneficence and the willingness to cause harm for the greater good. In this article, I argue that the impartial beneficence subscale, which breaks ground with previous research on utilitarian moral psychology, does not distinctively measure utilitarian moral judgment. I argue that Kantian ethics captures the all-encompassing impartial concern for the well-being of all human beings. The Oxford Utilitarianism Scale draws, in fact, a point of division that places Kantian and utilitarian theories on the same track. I suggest that the impartial beneficence subscale needs to be significantly revised in order to capture distinctively utilitarian judgments. Additionally, I propose that psychological research should focus on exploring multiple sources of the phenomenon of impartial beneficence without categorizing it as exclusively utilitarian.
Movement behavior of residual oil droplets and CO2: insights from molecular dynamics simulations
Authors: Luo Yongcheng , Xiao Hanmin , Liu Xiangui , Zhang Haiqin , Wu Zhenkai , Li Yaxiong , Zhao Xinli
Published: January 2022

After primary and secondary recovery of tight reservoirs, it becomes increasingly challenging to recover the remaining oil. Therefore, improving the recovery of the remaining oil is of great importance. Herein, molecular dynamics simulation (MD) of residual oil droplet movement behavior under CO2 displacement was conducted in a silica nanopores model. In this research, the movement behavior of CO2 in contact with residual oil droplets under different temperatures was analyzed, and the distribution of molecules number of CO2 and residual oil droplets was investigated. Then, the changes in pressure, kinetic energy, potential energy, van der Waals' force, Coulomb energy, long-range Coulomb potential, bond energy, and angular energy with time in the system after the contact between CO2 and residual oil droplets were studied. At last, the g(r) distribution of CO2–CO2, CO2-oil molecules, and oil molecules-oil molecules at different temperatures was deliberated. According to the results, the diffusion of CO2 can destroy residual oil droplets formed by the n-nonane and simultaneously peel off the n-nonane molecules that attach to SiO2 and graphene nanosheets (GN). The cutoff radius r of the CO2–CO2 is approximately 0.255 nm and that of the C–CO2 is 0.285 nm. The atomic force between CO2 and CO2 is relatively stronger. There is little effect caused by changing temperature on the radius where the maximum peak occurs in the radial distribution function (RDF)-g(r) of CO2–CO2 and C–CO2. The maximum peak of g(r) distribution of the CO2–CO2 in the system declines first and then rises with increasing temperature, while that of g(r) distribution of C–CO2 changes in the opposite way. At different temperatures, after the peak of g(r), its curve decreases with the increase in radius. The coordination number around C9H20 decreases, and the distribution of C9H20 becomes loose.
Riser and well casing analysis during drift-off: a coupled solution in the time domain
Authors: Guimarães Fabiano
Published: January 2022

One of the most serious incidents that can occur in offshore drilling and exploration is damage to the well structure and subsea components which can result in uncontrolled hydrocarbon release to the environment and present a safety hazard to rig personnel. Over decades, there have been substantial developments to the mathematical models and algorithms used to analyze the stresses on the related structure and to define the operational and integrity windows in which operations can proceed safely and where the mechanical integrity of the well is preserved. The purpose of this work is to present a time-domain solution to the system of equations that model the dynamic behavior of the riser and casing strings, when connected for well drilling/completion during the event of drift-off of the rig. The model combines a solution using finite differences for the riser dynamics and a recursive method to analyze the behavior of the casing in the soil. It allows for the coupling between the equations related to the riser and casing and for the coupling with the equations that describe the dynamics of the rig when station keeping capabilities are lost. The use of the forward–backward finite-differences coupled with the recursive method does not require linearization of the forces acting on the structure making it an ideal methodology for riser analysis while improving convergence. The findings of this study can help improve understanding of the impact of the watch circle limits to riser/well integrity, whether these limits are set based on a quasi-static drive-off/drift-off or fully dynamic. The gain in accuracy in using the fully coupled equations of drift-off dynamics, where there is interaction between the rig and the top of the riser during drive-off/drift-off, is evaluated, and the effects of varying the riser top tension and the compressive loads on the casing string are also analyzed. In particular, it is shown that the results of the fully coupled system of equations representing the dynamics of the riser and casing during drift-off/drive-off are less conservative than the quasi-static approach. Another important finding is that the gain in accuracy in coupling the top of the riser and the rig during drift-off/drive-off is not substantial, which indicates that solving separately the rig dynamics equations and the riser-casing equations is an approach that provides reasonable results with less computational effort. The model can also be used to evaluate wellhead and casing fatigue during the life of the intervention. Finally, the model limitations are discussed.
Machine learning algorithm for prediction of stuck pipe incidents using statistical data: case study in middle east oil fields
Authors: Elahifar Behzad , Hosseini Erfan
Published: January 2022

One of the most troublesome issues in the drilling industry is stuck drill pipes. Drilling activities will be costly and time-consuming due to stuck pipe issues. As a result, predicting a stuck pipe can be more useful. This study aims to use an artificial intelligence technology called hybrid particle swarm optimization neural network (PSO-based ANN) to predict the probability of a stuck pipe in a Middle East oil field. In this field, a total of 85 wells were investigated. Therefore, to predict this problem, we must examine and determine the role of drilling parameters by creating an appropriate model. In this case, an artificial neural network is used to solve and model the problem. In this way, by processing the parameters of wells with and without being stuck in this field, the stuck or non-stuck of drilling pipes in future wells is predicted. To create a PSO-based ANN model database, mud characteristics, geometry, hydraulic, and drilling parameters were gathered from well daily drilling reports. In addition, two databases for directional and vertical wells were established. There are two types of datasets used for each database: stuck and non-stuck. It was discovered that the PSO-based ANN model could predict the incidence of a stuck pipe with an accuracy of over 80% for both directional and vertical wells. This study divided data from several cases into four sections: 17 ½″, 12 ¼″, 8 ½″, and 6 1/8″. The key reasons for sticking and the mechanics have been thoroughly investigated for each section. The methodology presented in this paper enables the Middle East drilling industry to estimate the risk of stuck pipe occurrence during the well planning procedure.
Synthesis, characterisation and pre-evaluation of a novel terpolymer as pour point depressants to improve the Malaysian crude oil flowability
Authors: Elganidi Ibrahim , Elarbe Basem , Ridzuan Norida , Abdullah Norhayati
Published: January 2022

Wax deposition is considered one of the most serious operational issues in the crude oil pipelines. This issue occurs when the crude oil temperature decreases below the temperature of wax appearance and paraffin wax starts to precipitate on the pipelines’ inner walls. As a result, the crude oil flow is impeded because of the precipitated wax. The use of polymeric pour point depressants has obtained significant interest among researchers as an approach of wax control for enhancing the flowability of the waxy crude oil. PPD of poly(behenyl acrylate -co-stearyl methacrylate-co- maleic anhydride) (BA-co-SMA-co-MA) was facilely synthesised by the use of free radical polymerisation. The variation of the PPD structure was studied by choosing several essential parameters like monomers ratio, reaction time, initiator concentration, and reaction temperature. Furthermore, viscosity measurement, pour point, and cold finger apparatus have been employed to evaluate the efficiency of the synthesised Polymer. The chemical structure of poly(BA-co-SMA-co-MA) has been identified through the use of Fourier transform infrared as well as nuclear magnetic resonance. The experimental findings demonstrated that the ideal conditions for obtaining the highest yield were 1.5% initiator concentration, reaction time and temperature of 8 h and 100 °C, respectively, and monomer ratio of 1:1:1 (BA:SMA:MA). Under these ideal conditions, the prepared terpolymer reduced the crude oil viscosity at 30 °C and 1500 ppm from 7.2 to 3.2 mPa.s. The cold finger experiment demonstrated that after poly(BA-co-SMA-co-MA) was used as a wax inhibitor, the maximum efficiency of paraffin inhibition of 45.6% was achieved at 200 rpm and 5 °C. Besides, the best performance in depressing the pour point by ΔPP 14 ℃ observed at the concentration of 1500 ppm, which can change the growth characteristics of wax crystals and delay the aggregation of asphaltene and resin, thus effectively improving the flowability of crude oil.
Orthorexia nervosa and dieting in a non-clinical sample: a prospective study
Authors: Novara Caterina , Pardini Susanna , Visioli Francesco , Meda Nicola
Published: January 2022

Purpose

Orthorexia Nervosa (ON) is characterised by excessive attention to a dietary regimen perceived as healthy. A critical factor in the distinction between ON and other eating disorders (EDs) is the dichotomy of quality-versus-quantity of food intake. We investigated whether specific types of diet or dieting frequency are associated with orthorexic features, explored the overlap between ON and EDs symptoms, and examined which constructs are predictive of ON after 6 months.

Methods

A total of 1075 students (75.1% female, mean age 20.9) completed a set of questionnaires assessing Orthorexia, Eating Disorders, Obsessions and Compulsions, Anxiety and Depression; 358 individuals (79.9 female, mean age 20.9) agreed to participate in the study and completed the same questionnaires after 6 months. Different regression models were defined to investigate our hypothesis.

Results

Findings suggest that ON is associated with the number and type of diets followed over a lifetime. Moreover, participants with EDs, body dissatisfaction, or a dysfunctional idea of thinness are more likely to report a greater degree of ON features. After 6 months, the best predictors of ON characteristics are the same ON characteristics assessed at the first administration, with a significant role in the ideal of thinness.

Conclusions

ON is more frequent in individuals with a previous diagnosis of EDs and in individuals who followed a restrictive diet or a vegan/vegetarian one; the number of lifetime diets, beliefs, and behaviors related to the ideals of thinness or body dissatisfaction is common features of ON. Moreover, considering that having ON features in the past is the best ON predictor in the present, we can presume that ON is a construct stable over time.

Level of evidence

Level IV: Evidence obtained from multiple time series analysis such as case studies. (NB: Dramatic results in uncontrolled trials might also be regarded as this type of evidence).
Prenatal Diagnosis, Multimodality Workup and Postnatal Follow Up of Fetal Pancake Kidneys: A Rare Case Report
Authors: Kapoor Aakriti , Kapoor Tushar , Kapoor Aakaar , Kapoor Ravi , Kapoor Apurva
Published: January 2022

Pancake kidney results from failure of the kidneys to ascend, which may lead to fusion of the two renal masses. Reviewing the literature, this is the first case of antenatal diagnosis from India. No other associated extrarenal abnormalities were found. Postnatal follow up was also performed which confirmed the antenatal diagnosis.
Hierarchical clustering for multiple nominal data streams with evolving behaviour
Authors: Sangma Jerry W. , Sarkar Mekhla , Pal Vipin , Agrawal Amit , Yogita
Published: January 2022

Over the decade, a number of attempts have been made towards data stream clustering, but most of the works fall under clustering by example approach. There are a number of applications where clustering by variable approach is required which involves clustering of multiple data streams as opposed to clustering data examples in a data stream. Furthermore, a few works have been presented for clustering multiple data streams and these are applicable to numeric data streams only. Hence, this research gap has motivated current research work. In the present work, a hierarchical clustering technique has been proposed to cluster multiple data streams where data are nominal. To address the concept changes in the data streams splitting and merging of the clusters in the hierarchical structure are performed. The decision to split or merge is based on the entropy measure, representing the cluster’s degree of disparity. The performance of the proposed technique has been analysed and compared to Agglomerative Nesting clustering technique on synthetic as well as a real-world dataset in terms of Dunn Index, Modified Hubert $$\varGamma $$
Γ
statistic, Cophenetic Correlation Coefficient, and Purity. The proposed technique outperforms Agglomerative Nesting clustering technique for concept evolving data streams. Furthermore, the effect of concept evolution on clustering structure and average entropy has been visualised for detailed analysis and understanding.
How does fiscal austerity impact on poverty and inequality? The Spanish case
Authors: Campoy-Muñoz P. , Cardenete M. A. , Miguel-Vélez F. J. De , Pérez-Mayo J.
Published: January 2022

The aim of this paper is contributing to fill the gap between the macroeconomic effects of policy reforms and the microeconomic and social ones, considering simultaneously both kind of impacts. Regarding fiscal adjustments, concern about the sustainability of public deficit and debt resulting from the Great Recession led governments to adopt austerity measures in most European countries. Our analysis considers the redistributive effects of such adjustments for the Spanish economy by simulating a hypothetical reduction of public deficit and distinguishing between spending cuts and tax hikes. In terms of analytical approach, a Computable General Equilibrium (CGE) model and a microsimulation model are integrated to include the general equilibrium effects of these measures as well as the effects on income distribution. The results contribute to the growing but limited literature on the distributional effects of fiscal consolidations by showing that policymakers have to choose between more inequality or more poverty.
Feasibility of a Home-Based Task-Switching Training in Middle-Aged Caregivers
Authors: Lanfer Sarah Susanne Lütke , Enge Sören , Melzer Marlen , Wegge Jürgen , Kliegel Matthias
Published: January 2022

The current study aimed at investigating feasibility of a self-administered task-switching training in a middle-aged working population. Eighty-one caregivers (41–62 years old) were instructed to train at home 8 times either within a 7- or 14-day interval. Only 56.7% performed more than 50% of the instructed number of training sessions. However, compliant caregivers (who completed more than 4 training sessions) showed significant training gains and transfer to an untrained task-switching task. Although transfer effects to other cognitive tasks were not found, trained participants tended to report fewer everyday memory failures than a control group. In conclusion, the implementation of a home-based task-switching training in everyday life of caregivers is possible. However, there is only limited evidence for generalization of results of previous laboratory studies. Adherence and transfer to other cognitive tasks are discussed as important challenges in conveying laboratory findings into real life.
Study on bubble-induced turbulence in pipes and containers with Reynolds-stress models
Authors: Liao Yixiang , Ma Tian
Published: January 2022

Bubbly flow still represents a challenge for large-scale numerical simulation. Among many others, the understanding and modelling of bubble-induced turbulence (BIT) are far from being satisfactory even though continuous efforts have been made. In particular, the buoyancy of the bubbles generally introduces turbulence anisotropy in the flow, which cannot be captured by the standard eddy viscosity models with specific source terms representing BIT. Recently, on the basis of bubble-resolving direct numerical simulation data, a new Reynolds-stress model considering BIT was developed by Ma et al. (J Fluid Mech, 883: A9 (2020)) within the Euler—Euler framework. The objective of the present work is to assess this model and compare its performance with other standard Reynolds-stress models using a systematic test strategy. We select the experimental data in the BIT-dominated range and find that the new model leads to major improvements in the prediction of full Reynolds-stress components.