bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inevitability of the Poisson Bracket Structure of the Relativistic Constraints
Authors: Głowacki Jan 
Published: November 2021

AbstractThe purpose of this paper is to shed some fresh light on the long-standing conceptual question of the origin of the well-known Poisson bracket structure of the constraints that govern the canonical dynamics of generally relativistic field theories, i.e. geometrodynamics. This structure has long been known to be the same for a wide class of fields that inhabit the space-time, namely those with non-differential coupling to gravity. It has also been noticed that an identical bracket structure can be derived independently of any dynamical theory, by purely geometrical considerations in Lorentzian geometry. Here we attempt to provide the missing link between the dynamics and geometry, which we understand to be the reason for this structure to be of the specific kind. We achieve this by a careful analysis of the geometrodynamical approach, which allows us to derive the structure in question and understand it as a consistency requirement for any such theory. In order to stay close to the classical literature on the subject we stick to the metric formulation of general relativity, but the reasoning should carry over to any other formulation as long as the non-metricity tensor vanishes. The discussion section is devoted to derive some interesting consequences of the presented result in the context of reconstructing the Arnowitt–Deser–Misner (ADM) framework, thus providing a precise sense to the inevitability of the Einstein’s theory under minimal assumptions.
Mapping research trends of uveal melanoma: a bibliometric analysis
Authors: Li Senmao , Guo Yongwei , Hou Xiaoyi , Liu Jinhua , Fan Wanlin , Ju Sitong , Matos Philomena A. Wawer , Rokohl Alexander C. , Heindl Ludwig M. 
Published: November 2021

Abstract
Background
To explore the research trends for uveal melanoma with bibliometric methods using Web of Science Core Collection (WoSCC) and PubMed (PM).

Methods
To find UM-related studies, “uveal melanoma” was used as search term in the WoSCC and PM for the period time from 2000 to 2020. Bibliographic coupling analysis was used to investigate the journals with the highest number of UM-related publications. VOSviewer (VV) was used for mapping the knowledge domain and visualizing the co-occurrence of terms, authors, organizations, countries, co-citation literature, and keywords. The knowledge map based on WoSCC and PM was compared.

Results
In the WoSCC 3,748 articles were found, while in PM the search resulted in 3,403 articles. The number of original articles has steadily grown in general in the past two decades. The top ten authors were contributing to 23% (n = 856) of all publications, while the top 10 institutions published 41% (n = 1524) of all articles. The top 3 journals with the highest number of publications for UM-related research included Investigative ophthalmology & visual science, Ophthalmology, and British Journal of Ophthalmology. Co-occurrence analysis based on author keywords showed 6 clusters. The most frequent keywords included are metastasis, prognosis, and brachytherapy. The latest research hotspots focused on BAP1, immunotherapy and GNAQ.

Conclusions
Genetics and immunology are the latest research frontiers in uveal melanoma. There is a clear need for interdisciplinary, molecular and clinical research approaches to improve the fatal prognosis of uveal melanoma patients.
Well-Being and Perceived Stress of Adolescent Young Carers: A Cross-Sectional Comparative Study
Authors: Wepf Hannah , Leu Agnes 
Published: November 2021

AbstractAdolescent young carers have been described as a hidden group at risk of mental health problems. However, research has not yet clarified the effect of caring when considering the related family situation. We aimed to examine the impact of a caring role on adolescents’ mental health and to gain knowledge about adolescent young carers’ specific needs. We collected cross-sectional data from adolescents (15–21 years, N = 2525) recruited through educational institutions in German-speaking Switzerland. Based on self-reported answers regarding the presence or absence of a family member with health problems and youth’s caring activities, the participants were grouped into three subsamples. We compared mental health outcomes (well-being and perceived stress) in current carers and their peers, and we conducted multiple regression analyses for predicting these outcomes among all adolescents and the subsample of carers. Adolescent young carers had lower levels of well-being and higher levels of perceived stress than their peers. However, when controlling for background variables, well-being levels were lower only when carers were compared to adolescents from a healthy family background. Indicators of family instability predicted mental health outcomes independently of being a carer. More recognition for the caring role predicted better well-being and perceived stress outcomes, and more support in caring predicted better well-being but not perceived stress outcomes. The findings suggest that a caring role is not necessarily related to decreased well-being in adolescents, but it is associated with higher levels of perceived stress. The way professionals and services respond to young carers’ specific needs should be improved.
Family Structure Transitions: Prevalence and Physical Health Effects in Ethiopia, India, Peru, and Vietnam
Authors: Oldroyd Rebecca , Rahman Shazia , DeRose Laurie F. , Hadfield Kristin 
Published: November 2021

AbstractThis study aimed to identify the prevalence and physical health consequences of family structure transitions among children in Ethiopia, India, Peru, and Vietnam. In many high-income countries, family structure transitions are common, and research suggests that they can lead to worse physical health for children. However, we know little about either the prevalence or consequences of family structure transitions for children in low-and middle-income countries, who make up the vast majority of the world’s children. First, we estimated the number of family structure transitions by age 12 using four rounds of Young Lives data from four low-and middle-income countries (N = 8062, Ethiopia, India, Peru, and Vietnam) and validated our prevalence estimates with another dataset from these same countries. The proportion of children experiencing a family structure transition by age 12 was: 14.8% in Ethiopia, 5.6% in India, 22.0% in Peru, and 7.7% in Vietnam. We put these estimates in context by comparing them to 17 high- and upper-middle-income countries. Second, using linear mixed models, we found that family structure transitions were not directly associated with worse physical health for children in Ethiopia, India, Peru, and Vietnam. Children in Peru experienced higher rates of family structure transitions relative to children in the other Young Lives countries, and similar rates to many of the 17 comparison countries, yet physical health was unaffected. It is possible that in low-and middle-income countries, the environment may overwhelm family stability as a determinant of physical health.
Dutch preposition stranding and ellipsis: ‘Merchant’s Wrinkle’ ironed out
Authors: Griffiths James , Güneş Güliz , Lipták Anikó , Merchant Jason 
Published: November 2021

AbstractThis paper provides an explanation for the unexpected ban on preposition stranding bywh-R-pronouns under sluicing in Dutch. After showing that previous prosodic and syntactic explanations are untenable, we propose that the observed ban is a by-product of an EPP condition that applies in the PP domain in Dutch. Our analysis revolves around the idea that ellipsis bleeds EPP-driven movement, an idea that already has empirical support from independent patterns of ellipsis found in English and in other structural domains in Dutch. Our claim is that: (1) R-pronominalization involves a pronominal argument of P moving to the periphery of its extended PP domain (PlaceP) in order to satisfy a PP-internal EPP condition, (2) this EPP-driven movement is bled under sluicing, and (3) because SpecPlaceP is the ‘escape hatch’ through which R-pronouns must move in order to exit the PP domain to form preposition stranding configurations, bleeding the EPP-driven movement of R-pronouns to SpecPlaceP therefore precludes R-pronouns from undergoing thewh-movement required to form a sluicing configuration.
Incorporation of Functionalized Calcium Phosphate Nanoparticles in Living Cells
Authors: Rivas Manuel , Turon Pau , Alemán Carlos , Puiggalí Jordi , del Valle Luis J. 
Published: November 2021

AbstractIntracellular calcium (Ca2+) is a key signaling element that is involved in a great variety of fundamental biological processes. Thus, Ca2+ deregulation would be involved in the cancer cell progression and damage of mitochondrial membrane and DNA, which lead to apoptosis and necrosis. In this study, we have prepared amorphous calcium phosphate nanoparticles (ACP NPs) for studied their incorporation by endocytosis or electroporation to epithelial, endothelial and fibroblast cells (MCF-7, HUVEC and COS-1 cells, respectively). Our results showed that internalized ACP NPs have cytotoxic effects as a consequence of the increase of the intracellular calcium content. The endocytosis pathways showed a greater cytotoxic effect since calcium ions could easily be released from the nanoparticles and be accumulated in the lysosomes and mitochondria. In addition, the cytotoxic effect could be reversed when calcium ion was chelated with ethylene glycol-bis(2-aminoethylether)-N,N,N′,N′-tetraacetic acid (EGTA). Modification of ACP NPs by coating with different compounds based on phosphates was also evaluated. The results indicated a reduction of the cytotoxic effect, in the order polyphosphate < phosphonic acid < orthophosphate. A differential cytotoxic effect of ACP-NPs was observed in function of the cell type; the cytotoxic effect can be ordered as i.e., HUVEC > COS-1 > MCF-7. The greater cytotoxic effect caused by the increase of intracellular calcium that is observed in normal cells and the greater resistance of cancer cells suggests new perspectives for cancer research.
Digital Information Technology Use and Transnational Healthcare: A Population-Based Study on Older Russian-Speaking Migrants in Finland
Authors: Shin Young-Kyu , Koskinen Veera , Kouvonen Anne , Kemppainen Teemu , Olakivi Antero , Wrede Sirpa , Kemppainen Laura 
Published: November 2021

AbstractThis study examines the association between digital information technology (DIT) use and the utilization of transnational healthcare (THC) in older migrants, and investigates how this relationship depends on social integration or perceived discrimination in health services in the destination country. The data from a population-based study conducted in Finland in 2019, which targeted Russian-speaking residents aged 50 and above (n = 1082) nationwide, are analyzed. The analysis demonstrates that those who had a high level of DIT use were significantly more likely to use THC than those who had a low level of use. However, the findings do not show that the relationship depends on social integration or perceived discrimination. Older migrants can actively use transnational networks to address their health and well-being issues by using DIT and seeking healthcare abroad. Their health service use can be illustrated as an active process involving various geographical domains.
Flow theory: Advancing the two-dimensional conceptualization
Authors: Lavoie Raymond , Main Kelley , Stuart-Edwards Anastasia 
Published: November 2021

AbstractThis research advances the conceptualization and measurement of flow. The results of six studies (N = 2809) reveal that flow has two dimensions: “fluency,” which is comprised of experiences related to fluent thought and action; and “absorption,” which is based on sustained full attention. The results also demonstrate that the two dimensions have nuanced relationships with other variables. Specifically, while the fluency dimension is related to antecedents of flow (familiarity, skill, progress), the absorption dimension is not. Conversely, the absorption dimension was found to be strongly related to consequences of flow (behavioral intentions, presence), while the fluency dimension was not. Furthermore, we demonstrate that fluency-related experiences can give rise to the absorption-related experiences, which advances our understanding of how flow emerges. Finally, we develop a refined measure of flow called the two-dimensional-flow scale, and demonstrate its enhanced ability to capture variance in flow and other related variables in leisure contexts.
Application of computational approach in plastic pyrolysis kinetic modelling: a review
Authors: Armenise Sabino , Wong Syieluing , Ramírez-Velásquez José M. , Launay Franck , Wuebben Daniel , Nyakuma Bemgba B. , Rams Joaquín , Muñoz Marta 
Published: November 2021

AbstractDuring the past decade, pyrolysis routes have been identified as one of the most promising solutions for plastic waste management. However, the industrial adoption of such technologies has been limited and several unresolved blind spots hamper the commercial application of pyrolysis. Despite many years and efforts to explain pyrolysis models based on global kinetic approaches, recent advances in computational modelling such as machine learning and quantum mechanics offer new insights. For example, the kinetic and mechanistic information about plastic pyrolysis reactions necessary for scaling up processes is unravelling. This selective literature review reveals some of the foundational knowledge and accurate views on the reaction pathways, product yields, and other features of pyrolysis created by these new tools. Pyrolysis routes mapped by machine learning and quantum mechanics will gain more relevance in the coming years, especially studies that combine computational models with different time and scale resolutions governed by “first principles.” Existing research suggests that, as machine learning is further coupled to quantum mechanics, scientists and engineers will better predict products, yields, and compositions, as well as more complicated features such as ideal reactor design.
Collective teacher culture: exploring an elusive construct and its relations with teacher autonomy, belonging, and job satisfaction
Authors: Skaalvik Einar M. , Skaalvik Sidsel 
Published: November 2021

AbstractOne purpose of this study was to analyze relations between four possible indicators of a collective teacher culture by means of confirmatory factor analyses. The indicators were termed “shared goals values”, “value consonance”, “collective teacher efficacy”, and “supportive colleagues”. A second purpose was to explore relations between collective teacher culture and teachers’ experiences of autonomy, belonging, and job satisfaction. Participants were 760 Norwegian teachers in elementary school and middle school. The data were analyzed by means of confirmatory factor analyses and SEM analyses. The correlations between the four indicators of a collective culture ranged from .44 to .63 and both a model with first order factors and a model with a second order collective culture variable had good fit to the data. The analysis showed that a second order collective teacher culture variable was strongly and positively associated with the teachers’ experiences of autonomy, belonging, and job satisfaction.
Parallel signal detection for generalized spatial modulation MIMO systems
Authors: Garcia-Molla Victor M. , Simarro M. Angeles , Martínez-Zaldívar F. J. , Boratto Murilo , Alonso Pedro , Gonzalez Alberto 
Published: November 2021

AbstractGeneralized Spatial Modulation is a recently developed technique that is designed to enhance the efficiency of transmissions in MIMO Systems. However, the procedure for correctly retrieving the sent signal at the receiving end is quite demanding. Specifically, the computation of the maximum likelihood solution is computationally very expensive. In this paper, we propose a parallel method for the computation of the maximum likelihood solution using the parallel computing library OpenMP. The proposed parallel algorithm computes the maximum likelihood solution faster than the sequential version, and substantially reduces the worst-case computing times.
Occurrence of toxic metals and their selective pressure for antibiotic-resistant clinically relevant bacteria and antibiotic-resistant genes in river receiving systems under tropical conditions
Authors: Al Salah Dhafer Mohammed M. , Laffite Amandine , Sivalingam Periyasamy , Poté John 
Published: November 2021

AbstractThe co-occurrence of heavy metals, antibiotic-resistant bacteria (ARB) and antibiotic-resistance genes (ARGs) from hospital effluents spreading into the river receiving systems and evaluating associated risks are topics of scientific interest and still under-studied in developing countries under tropical conditions. To understand the selectors of the ARGs, we examined the occurrence of heavy metals (Cr, Co, Ni, Cu, Cd, Pb and Zn), associated ARB (β-lactam-resistant Escherichia coli, β-lactam-resistant Enterobacteriaceae, and carbapenem-resistant Enterobacteriaceae) and ARGs (blaOXA, blaCTX-M, blaIMP, blaTEM) in water and sediments from two sub-urban rivers receiving urban and hospital effluent waters in the Democratic Republic of the Congo (DRC). High abundances of ARB and ARGs were observed in all sediment samples. All the metal contents correlated negatively with grain size (− 0.94 ≤ r ≤  − 0.54, p < 0.05) except for Ni and positively with organic matter content and total copies of 16 s rRNA (0.42 ≤ r ≤ 0.79, p < 0.05), except for Ni and Zn. The metals had a significant positive correlation with the faecal indicator Enterococcus except for Ni and Cd (0.43 ≤ r ≤ 0.67, p < 0.05). Carbapenem-resistant Enterobacteriaceae correlated negatively with Zn (r =  − 0.44, p < 0.05) and positively with all the rest of toxic metals (0.58 ≤ r ≤ 1.0, p < 0.05). These results suggested that some metals had a great influence on the persistence of ARB and ARGs in sediments. Overall, this study strongly recommends the managing urban wastewater to preserve water resources used for human and agricultural purposes. Additionally, we recommend the utilizing biological indicators (faecal indicator bacteria, ARB, ARGs) when investigating urban wastewater pollutions.
The exact worst-case convergence rate of the gradient method with fixed step lengths for L-smooth functions
Authors: Abbaszadehpeivasti Hadi , de Klerk Etienne , Zamani Moslem 
Published: November 2021

AbstractIn this paper, we study the convergence rate of the gradient (or steepest descent) method with fixed step lengths for finding a stationary point of an L-smooth function. We establish a new convergence rate, and show that the bound may be exact in some cases, in particular when all step lengths lie in the interval (0, 1/L]. In addition, we derive an optimal step length with respect to the new bound.
Locus Coeruleus magnetic resonance imaging in cognitively intact elderly subjects
Authors: Giorgi Filippo Sean , Lombardo Francesco , Galgani Alessandro , Hlavata Hana , Della Latta Daniele , Martini Nicola , Pavese Nicola , Ghicopulos Irene , Baldacci Filippo , Coi Alessio , Scalese Marco , Bastiani Luca , Keilberg Petra , De Marchi Daniele , Fornai Francesco , Bonuccelli Ubaldo 
Published: November 2021

AbstractThe locus coeruleus is the main noradrenergic nucleus of the brain and is often affected in neurodegenerative diseases. Recently, magnetic resonance imaging with specific T1-weighted sequences for neuromelanin has been used to evaluate locus coeruleus integrity in patients with these conditions. In some of these studies, abnormalities in locus coeruleus signal have also been found in healthy controls and related to ageing. However, this would be at variance with recent post-mortem studies showing that the nucleus is not affected during normal ageing. The present study aimed at evaluating locus coeruleus features in a well-defined cohort of cognitively healthy subjects who remained cognitively intact on a one-year follow-up. An ad-hoc semiautomatic analysis of locus coeruleus magnetic resonance was applied. Sixty-two cognitively intact subjects aged 60–80 years, without significant comorbidities, underwent 3 T magnetic resonance with specific sequences for locus coeruleus. A semi-automatic tool was used to estimate the number of voxels belonging to locus coeruleus and its intensity was obtained for each subject. Each subject underwent extensive neuropsychological testing at baseline and 12 months after magnetic resonance scan. Based on neuropsychological testing 53 subjects were cognitively normal at baseline and follow up. No significant age-related differences in locus coeruleus parameters were found in this cohort. In line with recent post-mortem studies, our in vivo study confirms that locus coeruleus magnetic resonance features are not statistically significantly affected by age between 60 and 80 years, the age range usually evaluated in studies on neurodegenerative diseases. A significant alteration of locus coeruleus features in a cognitively intact elderly subject might be an early sign of pathology.
Is stroke incidence increased in survivors of adult cancers? A systematic review and meta-analysis
Authors: Turner Melanie , Murchie Peter , Derby Sarah , Ong Ariel Yuhan , Walji Lauren , McLernon David , Macleod Mary-Joan , Adam Rosalind 
Published: November 2021

Abstract

Purpose
Existing research hints that people living with and beyond cancer are at an increased risk of stroke. However, there is insufficient evidence to appropriately inform guidelines for specific stroke prevention or management for cancer patients. We conducted a systematic review and meta-analysis to describe and quantify stroke incidence in people living with and beyond cancer.

Methods
Medline, CINAHL, and EMBASE were searched for epidemiological studies comparing stroke incidence between cancer and non-cancer patients. Reviewers independently extracted data; random-effects meta-analyses and quality assessment were performed.

Results
Thirty-six studies were narratively synthesised. Meta-analysis was conducted using seven studies. Methodological quality was high for most studies. Study populations were heterogeneous, and the length of follow-up and risk factors varied. There was a variation in risk between different cancer types and according to stroke type: pancreatic (HR 2.85 (95% CI 2.43–3.36), ischaemic) (HR 2.28 (95% CI 1.43–3.63), haemorrhagic); lung (HR 2.33 (95% CI 1.63–3.35), ischaemic) (HR 2.14 (95% CI 1.45–3.15), haemorrhagic); and head and neck (HR 1.54 (95% CI 1.40–1.69), haemorrhagic) cancers were associated with significantly increased incidence of stroke. Risk is highest within the first 6 months of diagnosis. Narrative synthesis indicated that several studies also showed significantly increased incidence of stroke in individuals with colorectal cancer, breast cancer, ovarian cancer, nasopharyngeal cancer, leukaemia, and myeloma, and those who have received radiotherapy for head and neck cancers and platinum-based chemotherapy may also have higher stroke incidence.

Conclusions
Stroke incidence is significantly increased after diagnosis of certain cancers.

Implications for Cancer Survivors
Cardiovascular risk should be assessed during cancer survivorship care, with attention to modifying shared cancer/cardiovascular risk factors.