bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reorganization of brain structural networks in aging: A longitudinal study
Authors: Coelho Ana , Fernandes Henrique M. , Magalhães Ricardo , Moreira Pedro S. , Marques Paulo , Soares José M. , Amorim Liliana , Portugal‐Nunes Carlos , Castanho Teresa , Santos Nadine Correia , Sousa Nuno 
Published: February 2021

AbstractNormal aging is characterized by structural and functional changes in the brain contributing to cognitive decline. Structural connectivity (SC) describes the anatomical backbone linking distinct functional subunits of the brain and disruption of this communication is thought to be one of the potential contributors for the age‐related deterioration observed in cognition. Several studies already explored brain network's reorganization during aging, but most focused on average connectivity of the whole‐brain or in specific networks, such as the resting‐state networks. Here, we aimed to characterize longitudinal changes of white matter (WM) structural brain networks, through the identification of sub‐networks with significantly altered connectivity along time. Then, we tested associations between longitudinal changes in network connectivity and cognition. We also assessed longitudinal changes in topological properties of the networks. For this, older adults were evaluated at two timepoints, with a mean interval time of 52.8 months (SD = 7.24). WM structural networks were derived from diffusion magnetic resonance imaging, and cognitive status from neurocognitive testing. Our results show age‐related changes in brain SC, characterized by both decreases and increases in connectivity weight. Interestingly, decreases occur in intra‐hemispheric connections formed mainly by association fibers, while increases occur mostly in inter‐hemispheric connections and involve association, commissural, and projection fibers, supporting the last‐in‐first‐out hypothesis. Regarding topology, two hubs were lost, alongside with a decrease in connector‐hub inter‐modular connectivity, reflecting reduced integration. Simultaneously, there was an increase in the number of provincial hubs, suggesting increased segregation. Overall, these results confirm that aging triggers a reorganization of the brain structural network.
Employee engagement and organizational change initiatives: Does transformational leadership, valence, and trust make a difference?
Authors: Islam M. Nazmul , Furuoka Fumitaka , Idris Aida 
Published: February 2021

AbstractThe research investigates the role of transformationalleadership in enhancing employee engagement during organizational change, and the individual and sequential mediating role of valence and trust in leadership. Based on cross‐sectional data from a survey of employees in Bangladesh's banking sector, the study uses structural equation modeling to test four hypotheses related to employee engagement and organizational change. The results showed that transformational leadership positively associated with employee engagement, and that both valence and trust in leadership individually and sequentially mediate the relationship between transformational leadership and employee engagement. The research contributes to the areas of organizational change management and human resource management by clarifying the impact of transformational leadership on employee engagement. It also provides practical guidance on improving employee engagement in Bangladesh's banking sector, and elsewhere, during periods of organizational change.
Distribution of n‐alkan‐2‐ones in Qionghai Lake sediments, southwest China, and its potential for late Quaternary paleoclimate reconstruction
Authors: Wang Gen , Wang Yongli , Wei Zhifu , He Wei , Zhang Ting , Ma Xueyun , Yu Xiaoli 
Published: February 2021

AbstractStudies on long‐chain n‐alkan‐2‐ones from lake sediments remain sparse. In this study, we present an n‐alkan‐2‐one record from Qionghai Lake, southwest China, to assess the paleoclimate significance of variations in their compositions. A homologous series of n‐alkan‐2‐ones ranging from C21 to C35 were identified, with maximum concentrations of the C29 or C31 chain lengths and a strong odd‐over‐even predominance. This type of n‐alkan‐2‐one is considered to derive mainly from microbial oxidation of the corresponding n‐alkanes, and partial inputs from plants. The n‐alkan‐2‐one‐derived average chain length (ACL) and carbon preference index (CPI) values changed significantly over the past 28k cal a bp, consistent with the sediment grain size and n‐alkane proxies from the same core. Generally, the high CPI27‐33‐ket and low ACL27‐33‐ket values indicated cold and dry climates such as for the Last Glacial Maximum (23.2–19.7k cal a bp), Heinrich 1 event (17.6–15.6k cal a bp) and Younger Dryas (12.8–11.6k cal a bp), but low CPI27‐33‐ket and high ACL27‐33‐ket values denoted a warm and humid Holocene Climatic Optimum (7.0–4.3k cal a bp). Therefore, n‐alkan‐2‐ones have great paleoclimatic potential and can be applied together with other biomarkers to reconstruct a reliable paleoclimate record in lake sediments.
As Basket and Papu: Making Manus Social Fabric
Authors: Rooney Michelle Nayahamui 
Published: February 2021

ABSTRACTBetween 2012 and 2019, Manus Island, Papua New Guinea, hosted Australia's offshore detention centre for asylum seekers and refugees, known as the Regional Processing Centre (RPC). This paper analyses some of the social impacts of the RPC on Lorengau town, the urban centre of Manus, through the analytical lens of the Manus idiom, as basket (Tok Pisin). Materially this refers to the everyday Manus basket whilst metaphorically, it refers to an individual's or community's social, cultural, political and economic base. First, I examine asylum seekers and refugees as a social category that emerged during this period when they were referred to as papu by locals. Papu is an honorific kinship term for grandfather or elder man; for men who are symbols for family identity, social belonging, and rights to land. Second, I examine the changing materiality of Lorengau's markets as indicative of wider societal transformations and dissonance brought about by the RPC. My ethnographic data are based on long term involvement in Manus, including three recent visits to Lorengau in 2017, 2018, and 2019 where I studied the social impacts and the changing social practices of Manus people in response to the RPC.
Functional relationships of three NFU proteins in the biogenesis of chloroplastic iron‐sulfur clusters
Authors: Satyanarayan Manasa B. , Zhao Jun , Zhang Jessica , Yu Fei , Lu Yan 
Published: February 2021

AbstractIron‐sulfur clusters are required in a variety of biological processes. Biogenesis of iron‐sulfur clusters includes assembly of iron‐sulfur clusters on scaffold complexes and transfer of iron‐sulfur clusters to recipient apoproteins by iron‐sulfur carriers, such as nitrogen‐fixation‐subunit‐U (NFU)‐type proteins. Arabidopsis thaliana has three plastid‐targeted NFUs: NFU1, NFU2, and NFU3. We previously discovered that nfu2−/− nfu3−/− mutants are embryo lethal. The lack of viable nfu2−/− nfu3−/− mutants posed a serious challenge. To overcome this problem, we characterized nfu2‐1−/− nfu3‐2+/‐ and nfu2‐1+/‐ nfu3‐2−/− sesquimutants. Simultaneous loss‐of‐function mutations in NFU2 and NFU3 have an additive effect on the declines of 4Fe‐4S‐containing PSI core subunits. Consequently, the sesquimutants had much lower PSI and PSII activities, much less chlorophyll, and much smaller plant sizes, than nfu2‐1 and nfu3‐2 single mutants. These observations are consistent with proposed roles of NFU3 and NFU2 in the biogenesis of chloroplastic 4Fe‐4S. By performing spectroscopic and in vitro reconstitution experiments, we found that NFU1 may act as a carrier for chloroplastic 4Fe‐4S and 3Fe‐4S clusters. In line with this hypothesis, loss‐of‐function mutations in NFU1 resulted in significant declines in 4Fe‐4S‐ and 3Fe‐4S‐containing chloroplastic proteins. The declines of PSI activity and 4Fe‐4S‐containing PSI core subunits in nfu1 mutants indicate that PSI is the main target of NFU1 action. The reductions in 4Fe‐4S‐containing PSI core proteins and PSI activity in nfu3‐2, nfu2‐1, and nfu1 single mutants suggest that all three plastid‐targeted NFU proteins contribute to the biogenesis of chloroplastic 4Fe‐4S clusters. Although different insertion sites of T‐DNA lines may cause variations in phenotypic results, mutation severity could be an indicator of the relative importance of the gene product. Our results are consistent with the hypothesis that NFU3 contributes more than NFU2 and NFU2 contributes more than NFU1 to the production of 4Fe‐4S‐containing PSI core subunits.
Properties and applications of precision oligomer materials; where organic and polymer chemistry join forces
Authors: van Genabeek Bas , Lamers Brigitte A. G. , Hawker Craig J. , Meijer E. W. , Gutekunst Will R. , Schmidt Bernhard V. K. J. 
Published: February 2021

AbstractPrecise oligomeric materials constitute a growing area of research with implications for various applications as well as fundamental studies. Notably, this field of science which can be termed macro‐organic chemistry, draws inspiration from both traditional polymer chemistry and organic synthesis, combining the molecular precision of organic chemistry with the materials properties of macromolecules. Discrete oligomers enable access to unprecedented materials properties, for example, in self‐assembled structures, crystallization, or optical properties. The degree of control over oligomer structures resembles many biological systems and enables the design of materials with tailored properties and the development of fundamental structure–property relationships. This Review highlights recent developments in macro‐organic chemistry from synthetic concepts to materials properties, with a focus on self‐assembly and molecular recognition. Finally, an outlook for future research directions is provided.
Restless sleep disorder, restless legs syndrome, and periodic limb movement disorder—Sleep in motion!
Authors: DelRosso Lourdes M. , Mogavero Maria P. , Ferri Raffaele 
Published: February 2021

AbstractSleep‐related movement disorders (SRMDs) represent an important part of pediatric sleep disorders. The most common complaint in SRMD is restless sleep at night. Restless sleep is reported in up to 80% of children with restless legs syndrome (RLS) and children with periodic limb movements of sleep (PLMS) disorder (PLMD). However, restless sleep causing daytime behavioral consequences can be seen in children without another apparent condition and has recently been identified as a new independent primary pediatric sleep disorder, called restless sleep disorder (RSD). This study describes these three main SRMDs (RSD, RLS, and PLMD), explains the new consensus criteria for RSD, emphasizes the rapidly evolving areas of research in this field, and proposes recommendations for future research. In particular, the published data constitute convincing evidence that sleep‐related movements are disruptors of sleep quality and continuity. However, while important advancements have recently been reported in adults, a detailed analysis of the phenomenology and consequences of sleep‐related movements has just started in children. New approaches, standardized diagnostic methods, and specific guidelines are needed in the field of pediatric SRMD.
Comparison of total laparoscopic gastropexy with the Ethicon Securestrap fixation device versus knotless barbed suture in dogs
Authors: Lacitignola Luca , Crovace Alberto Maria , Fracassi Laura , Di bella Caterina , Madaro Letizia , Staffieri Francesco 
Published: February 2021

AbstractBackground: This study evaluated the feasibility and efficacy of a laparoscopic absorbable fixation device (Securestrap) in total laparoscopic gastropexy in dogs susceptible to gastric dilatation‐volvulus (GDV) compared to laparoscopic gastropexy performed with a barbed suture. We hypothesised that both techniques provide suitable gastropexy.Methods: The gastropexy was performed by straps (TLG‐SS group, n = 6) or with a barbed suture (TLG‐Vloc group, n = 6). The total surgery time, gastropexy time, the number of straps used and suture bites were recorded. Clinical and ultrasound investigations were performed during follow‐up.Results: The total surgery time was 30 minutes in the TLG‐SS, while it was 46.66 minutes in the TLG‐Vloc. In the TLG‐SS group, gastropexy time was 13 minutes, while 36.3 minutes in the TLG‐Vloc. The number of straps employed in TLG‐SS was 9, while seven bites were employed in TLG‐Vloc. Linear regression analysis of gastropexy time versus the number of procedures was highly correlated (r2 = 0.84) in the TLG‐SS. Complications, clinical and ultrasound findings did not differ between the two techniques at 90 days post‐surgery.Conclusion: TLG‐SS laparoscopic technique can be employed safely and effectively in less time and is associated with a relatively short learning curve, which could encourage the widespread use of prophylactic laparoscopic gastropexy.
Crystal structures of (Et4N)2C2S6, (Et4N)2C2S5, (Et4N)2CS4, (Et4N)HCS3, (Et4N)2CS3 ⋅ 2H2O and (Et4N)2CS4‐y ⋅ yH2O (y=0.69).
Authors: Bernhardt Eduard 
Published: February 2021

AbstractThe crystal structures of (Et4N)2C2S6, (Et4N)2C2S5, (Et4N)2CS4, (Et4N)HCS3, (Et4N)2CS3 ⋅ 2H2O and (Et4N)2CS4‐y ⋅ yH2O (y=0.69) were determined by single‐crystal X‐ray diffraction analysis at 150 K. For the first time, salts with the C2S52− and HCS3− anions could be synthesized.
Local Institutions, Collective Action, and Divergent Adaptation: Case from Agro-Pastoral Niger
Authors: Snorek Julie 
Published: February 2021

AbstractAdaptation is a highly contextual process, framed by institutions. When one group’s adaptation to climate hazards reduces another’s adaptive capacity, this is called divergent adaptation. The nuances of divergent adaptation are revealed in how institutions influence divergent adaptation outcomes, either to exacerbate conflict or to bring about greater peace and cooperation. By examining the sometimes conflicting adaptations of pastoralists and agro-pastoralists in Niger, this chapter describes the process of divergent adaptation through an institutional analysis from multiple scales. At the national scale, climate change adaptation policies and perspectives are entrenched in sedentarization politics vis-à-vis pastoral livelihoods. At the local scale, pastoralists take a defensive position as an adaptation pathway, to ensure secure passage with their livestock to water and pasture. However, in localities where local institutional actors have enhanced collective action arenas in which pastoral and agro-pastoral groups are represented, conflict dynamics are abated. Climate adaptation is not without conflict; however, local and sub-national institutions are critical to providing opportunities for collective action, cooperation, and peace in the context of divergent adaptation. Based on these findings, it is recommended that conflict and adaptation management and planning be integrated at multiple scales.
Conclusion: Insights from Theory and Practice
Authors: Sweijs Tim , Osinga Frans 
Published: February 2021

AbstractStrategists are fond of saying that the nature of war is immutable, but its character is not. Even Von Clausewitz, whose very objective was to develop a general theory of war, held that every age has “its own kind of war, its own limiting conditions, and its own peculiar preconceptions.” The same can be said for strategy. History offers ample examples of strategic concepts that guide how means are to be connected to political ends in order to defeat adversaries in particular historical contexts. Warfighting concepts have included dislocation and exhaustion to target the adversary’s will, and attrition and annihilation to deal with its capabilities.
Fun with F24
Authors: Harrison Sarah M. , Paquette Natalie M. , Persson Daniel , Volpato Roberto 
Published: February 2021

Abstract
We study some special features of F24, the holomorphic c = 12 superconformal field theory (SCFT) given by 24 chiral free fermions. We construct eight different Lie superalgebras of “physical” states of a chiral superstring compactified on F24, and we prove that they all have the structure of Borcherds-Kac-Moody superalgebras. This produces a family of new examples of such superalgebras. The models depend on the choice of an $$ \mathcal{N} $$
N
= 1 supercurrent on F24, with the admissible choices labeled by the semisimple Lie algebras of dimension 24. We also discuss how F24, with any such choice of supercurrent, can be obtained via orbifolding from another distinguished c = 12 holomorphic SCFT, the $$ \mathcal{N} $$
N
= 1 supersymmetric version of the chiral CFT based on the E8 lattice.
Momentum amplituhedron meets kinematic associahedron
Authors: Damgaard David , Ferro Livia , Łukowski Tomasz , Moerman Robert 
Published: February 2021

Abstract
In this paper we study a relation between two positive geometries: the momen- tum amplituhedron, relevant for tree-level scattering amplitudes in $$ \mathcal{N} $$
N
= 4 super Yang-Mills theory, and the kinematic associahedron, encoding tree-level amplitudes in bi-adjoint scalar φ3 theory. We study the implications of restricting the latter to four spacetime dimensions and give a direct link between its canonical form and the canonical form for the momentum amplituhedron. After removing the little group scaling dependence of the gauge theory, we find that we can compare the resulting reduced forms with the pull-back of the associahedron form. In particular, the associahedron form is the sum over all helicity sectors of the reduced momentum amplituhedron forms. This relation highlights the common sin- gularity structure of the respective amplitudes; in particular, the factorization channels, corresponding to vanishing planar Mandelstam variables, are the same. Additionally, we also find a relation between these canonical forms directly on the kinematic space of the scalar theory when reduced to four spacetime dimensions by Gram determinant constraints. As a by-product of our work we provide a detailed analysis of the kinematic spaces relevant for the four-dimensional gauge and scalar theories, and provide direct links between them.
The present and future of four top operators
Authors: Banelli Giovanni , Salvioni Ennio , Serra Javi , Theil Tobias , Weiler Andreas 
Published: February 2021

Abstract
We study the phenomenology of a strongly-interacting top quark at future hadron and lepton colliders, showing that the characteristic four-top contact operators give rise to the most significant effects. We demonstrate the extraordinary potential of a 100 TeV proton-proton collider to directly test such non-standard interactions in four-top production, a process that we thoroughly analyze in the same-sign dilepton and trilepton channels, and explore in the fully hadronic channel. Furthermore, high-energy electron-positron colliders, such as CLIC or the ILC, are shown to exhibit an indirect yet remarkable sensitivity to four-top operators, since these constitute, via renormalization group evolution, the leading new-physics deformations in top-quark pair production. We investigate the impact of our results on the parameter space of composite Higgs models with a strongly-coupled (right-handed) top quark, finding that four-top probes provide the best sensitivity on the compositeness scale at the future energy frontier. In addition, we investigate mild yet persisting LHC excesses in multilepton plus jets final states, showing that they can be consistently described in the effective field theory of such a new-physics scenario.
New scenario for aligned Higgs couplings originated from the twisted custodial symmetry at high energies
Authors: Aiko Masashi , Kanemura Shinya 
Published: February 2021

Abstract
We investigate a new scenario of the two Higgs doublet model, where the current experimental data for the electroweak rho parameter and those for the Higgs boson couplings can be simultaneously explained. In this scenario, the two Higgs doublet model is supposed to be a low energy effective theory up to a high energy scale Λ, above which a fundamental theory should appear. It is assumed that the Higgs potential respects a global symmetry at Λ (the twisted custodial symmetry), which is to be given as a consequence of the global symmetry structure of the fundamental theory above Λ. By the analysis using one-loop renormalization group equations, the above experimental data can be explained in a natural way even when the masses of the extra Higgs bosons are near the electroweak scale. We also discuss the predictions on the mass spectrum of the additional Higgs bosons and also those on the coupling constants of the standard-model-like Higgs boson, which make it possible to test this scenario at the current and future collider experiments.
The Zakharov–Kuznetsov equation in high dimensions: small initial data of critical regularity
Authors: Herr Sebastian , Kinoshita Shinya 
Published: February 2021

AbstractThe Zakharov–Kuznetsov equation in spatial dimension $$d\ge 5$$

d
≥
5

is considered. The Cauchy problem is shown to be globally well-posed for small initial data in critical spaces, and it is proved that solutions scatter to free solutions as $$t \rightarrow \pm \infty $$

t
→
±
∞

. The proof is based on i) novel endpoint non-isotropic Strichartz estimates which are derived from the $$(d-1)$$

(
d
-
1
)

-dimensional Schrödinger equation, ii) transversal bilinear restriction estimates, and iii) an interpolation argument in critical function spaces. Under an additional radiality assumption, a similar result is obtained in dimension $$d=4$$

d
=
4

.
RFID-tagged amazonian stingless bees confirm that landscape configuration and nest re-establishment time affect homing ability
Authors: Costa L. , Nunes-Silva P. , Galaschi-Teixeira J. S. , Arruda H. , Veiga J. C. , Pessin G. , de Souza P. , Imperatriz-Fonseca V. L. 
Published: February 2021

AbstractBee flight capacity determines the area that a colony can exploit, and this knowledge is essential to formulate management and conservation strategies for each species. In this study, we evaluated the flight capacity ofMelipona seminigrausing radio frequency identification (RFID). Three questions were addressed: Do the RFID tags affect the flight ofM. seminigraworkers? What is the effect of the landscape on foraging activity? Does the time since the colony was re-established affect the flight range of foragers? Our results indicate that the RFID tag used does not affect the flight ability ofM. seminigra. Bees marked with nontoxic paint vs. RFID tags had the same return ratio and return time to the colony of origin. Flight capacity was affected by the landscape, because the return rate to the colonies was higher from the tested vegetated area than from the sterile area. The time elapsed since the bee colony re-establishment also affected the flight range because the return rate increased with time since the colony was relocated in the new site. We estimate thatM. seminigraworkers make foraging flights of approximately 1000 m from the colony and that the maximum flight range is 5000 m. Colonies of this species take more than 1 or 2 months to be able to fully exploit a landscape.