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1. Accurate assembly of ferrocene-functionalized {Ti₂₂Fc₄} clusters with photocatalytic amine oxidation activity

Author:
Han, Er-Meng; Yu, Wei-Dong; Li, Lei-Jiao; Yi, Xiao-Yi; Yan, Jun; Liu, Chao
Source:
Chemical communications 2021 v.57 no.22 pp. 2792-2795
ISSN:
1364-548X
Subject:
topology,   etc   ; oxidation; photocatalysis; photocatalysts;     Show all 4 Subjects
Abstract:
... We report here the synthesis of a ferrocene-functionalized {Ti₂₂Fc₄} cluster with a ‘dimer-of-clusters’ topology, which represents the largest Ti-oxo cluster (TOC) modified with organometallic groups ever reported. The exact assembly path of {Ti₂₂Fc₄} can be inferred from its two substructures, {Ti₁₁Fc₂} and {Ti₅Fc}, which can also be synthesized independently through subtle changes in reaction co ...
DOI:
10.1039/d1cc00019e

2. Passing the framework skeleton and properties of coordination materials onto organic framework materials

Author:
Wang, Xuan; Dong, Ming-Jie; Chen, Kai; Liu, Zi-Kun; Wu, Chuan-De
Source:
Chemical communications 2021 v.57 no.11 pp. 1348-1351
ISSN:
1364-548X
Subject:
topology,   etc   ; porosity; skeleton;     Show all 3 Subjects
Abstract:
... A practically applicable strategy for transforming fragile metal–organic frameworks (MOFs) into highly stable and ordered organic framework materials (OFMs) is developed by replacing the labile coordination bonds in MOFs with stable covalent bonds in OFMs, which exhibit hypothetically approximated topology, porosity and properties of the parent MOFs by merging the advantages of MOFs and porous org ...
DOI:
10.1039/d0cc07091b

3. Heuristics for unrooted, unranked, and ranked anomaly zones under birth-death models

Author:
Kim, Anastasiia; Degnan, James H.
Source:
Molecular phylogenetics and evolution 2021 v.161 pp. 107162
ISSN:
1055-7903
Subject:
topology,   etc   ; genes; phylogeny; probability; trees;     Show all 5 Subjects
Abstract:
... Species trees that can generate a nonmatching gene tree topology that is more probable than the topology matching the species tree are said to be in an anomaly zone. We introduce some heuristic approaches to infer whether species trees are in anomaly zones when it is difficult or impossible to compute the entire distribution of gene tree topologies. Here, probabilities of unrooted, unranked, and r ...
DOI:
10.1016/j.ympev.2021.107162

4. Collapsing dubiously resolved gene-tree branches in phylogenomic coalescent analyses

Author:
Simmons, Mark P.; Gatesy, John
Source:
Molecular phylogenetics and evolution 2021 v.158 pp. 107092
ISSN:
1055-7903
Subject:
topology,   etc   ; data collection; genes; phylogeny;     Show all 4 Subjects
Abstract:
... In two-step coalescent analyses of phylogenomic data, gene-tree topologies are treated as fixed prior to species-tree inference. Although all gene-tree conflict is assumed to be caused by lineage sorting when applying these methods, in empirical datasets much of the conflict can be caused by estimation error. Weakly supported and even arbitrarily resolved clades are important sources of this estim ...
DOI:
10.1016/j.ympev.2021.107092

5. Preservation Value in Socio-Ecological Systems

Author:
Dragicevic, Arnaud Z.; Shogren, Jason F.
Source:
Ecological modelling 2021 v.443 pp. 109451
ISSN:
0304-3800
Subject:
topology,   etc   ; social environment; sustainable development;     Show all 3 Subjects
Abstract:
... We develop a model that reveals the preservation value of maintaining connectivity within a socio-ecological system (SES). By means of a multiplex network, built from the layers composing the sustainability Venn diagram, we define two measures of preservation value of inter- and intra-layer connections. Most policymakers and researchers have tended to assume that all elements within an SES are unc ...
DOI:
10.1016/j.ecolmodel.2021.109451

6. Putting food access in its topological place: thinking in terms of relational becomings when mapping space

Author:
Carolan, Michael
Source:
Agriculture and human values 2021 v.38 no.1 pp. 243-256
ISSN:
0889-048X
Subject:
topology,   etc   ; agriculture; data collection; humans;     Show all 4 Subjects
Abstract:
... This paper adopts a relational, also known as a topological, approach to food accessibility—the idea that food spaces are best understood as relational becomings rather than as voids filled exclusively with mass (immutable materiality) and address (geospatial coordinates). It is animated by an experimental spirit, in terms of the methods employed, the data collected, and by how those data are brou ...
DOI:
10.1007/s10460-020-10149-y

7. Combining centrality indices: Maximizing the predictability of keystone species in food webs

Author:
Gouveia, Catarina; Móréh, Ágnes; Jordán, Ferenc
Source:
Ecological indicators 2021 v.126 pp. 107617
ISSN:
1470-160X
Subject:
topology,   etc   ; ecosystems; food webs; keystone species;     Show all 4 Subjects
Abstract:
... Network analysis offers a rich toolkit to study various graph models in biology. In ecology, centrality indices have been suggested to indicate keystone species in interaction networks and to quantify their importance in an ecosystem. There is a large number of centrality indices, however, and it is often unclear what is their precise biological meaning, how are they related to each other and whic ...
DOI:
10.1016/j.ecolind.2021.107617

8. Phylogeny and classification of Odonata using targeted genomics

Author:
Bybee, Seth M.; Kalkman, Vincent J.; Erickson, Robert J.; Frandsen, Paul B.; Breinholt, Jesse W.; Suvorov, Anton; Dijkstra, Klaas-Douwe B.; Cordero-Rivera, Adolfo; Skevington, Jeffrey H.; Abbott, John C.; Sanchez Herrera, Melissa; Lemmon, Alan R.; Moriarty Lemmon, Emily; Ware, Jessica L.
Source:
Molecular phylogenetics and evolution 2021 v.160 pp. 107115
ISSN:
1055-7903
Subject:
topology,   etc   ; Zygoptera; genomics; hybrids; insects; introgression; monophyly;     Show all 7 Subjects
Abstract:
... Dragonflies and damselflies are a charismatic, medium-sized insect order (~6300 species) with a unique potential to approach comparative research questions. Their taxonomy and many ecological traits for a large fraction of extant species are relatively well understood. However, until now, the lack of a large-scale phylogeny based on high throughput data with the potential to connect both perspecti ...
DOI:
10.1016/j.ympev.2021.107115

9. Confinement-guided photophysics in MOFs, COFs, and cages

Author:
Leith, Gabrielle A.; Martin, Corey R.; Mayers, Jacob M.; Kittikhunnatham, Preecha; Larsen, Randy W.; Shustova, Natalia B.
Source:
Chemical Society reviews 2021 v.50 no.7 pp. 4382-4410
ISSN:
1460-4744
Subject:
topology,   etc   ; biomimetics; fluorescence; ligands; white light;     Show all 5 Subjects
Abstract:
... In this review, the dependence of the photophysical response of chromophores in the confined environments associated with crystalline scaffolds, such as metal–organic frameworks (MOFs), covalent-organic frameworks (COFs), and molecular cages, has been carefully evaluated. Tunability of the framework aperture, cavity microenvironment, and scaffold topology significantly affects emission profiles, q ...
DOI:
10.1039/d0cs01519a

10. DNA topoisomerases: Advances in understanding of cellular roles and multi‐protein complexes via structure‐function analysis

Author:
McKie, Shannon J.; Neuman, Keir C.; Maxwell, Anthony
Source:
BioEssays 2021 v.43 no.4 pp. e2000286
ISSN:
0265-9247
Subject:
topology,   etc   ; DNA; DNA topoisomerase; dissection; metabolism;     Show all 5 Subjects
Abstract:
... DNA topoisomerases, capable of manipulating DNA topology, are ubiquitous and indispensable for cellular survival due to the numerous roles they play during DNA metabolism. As we review here, current structural approaches have revealed unprecedented insights into the complex DNA‐topoisomerase interaction and strand passage mechanism, helping to advance our understanding of their activities in vivo. ...
DOI:
10.1002/bies.202000286

11. Explore training self-organizing map methods for clustering high-dimensional flood inundation maps

Author:
Chang, Li-Chiu; Wang, Wu-Han; Chang, Fi-John
Source:
Journal of hydrology 2021 v.595 pp. 125655
ISSN:
0022-1694
Subject:
topology,   etc   ; data collection; hydrology; models; probability; Taiwan;     Show all 6 Subjects
Abstract:
... The Self-Organizing Map (SOM) can supportively organize complex datasets such as highly dimensional flood inundation maps. Nevertheless, SOM may produce distinct patterns after being trained with identical samples or may not converge in clustering highly dimensional datasets, which causes usability concerns and prevents its applications from a broader spectrum. Motivated by such concerns, two trai ...
DOI:
10.1016/j.jhydrol.2020.125655

12. Grazing and the vanishing complexity of plant association networks in grasslands

Author:
Génin, Alexandre; Dutoit, Thierry; Danet, Alain; le Priol, Alice; Kéfi, Sonia
Source:
Oikos 2021 v.130 no.4 pp. 541-552
ISSN:
0030-1299
Subject:
topology,   etc   ; community structure; grasslands; herbaceous plants; sheep;     Show all 5 Subjects
Abstract:
... Interactions are key drivers of the functioning and fate of plant communities. A traditional way to measure them is to use pairwise experiments, but such experiments do not scale up to species‐rich communities. For those, using association networks based on spatial patterns may provide a more realistic approach. While this method has been successful in abiotically‐stressed environments (alpine and ...
DOI:
10.1111/oik.07850

13. Honeycomb layered oxides: structure, energy storage, transport, topology and relevant insights

Author:
Kanyolo, Godwill Mbiti; Masese, Titus; Matsubara, Nami; Chen, Chih-Yao; Rizell, Josef; Huang, Zhen-Dong; Sassa, Yasmine; Månsson, Martin; Senoh, Hiroshi; Matsumoto, Hajime
Source:
Chemical Society reviews 2021 v.50 no.6 pp. 3990-4030
ISSN:
1460-4744
Subject:
topology,   etc   ; cations; electrochemistry; energy; health services;     Show all 5 Subjects
Abstract:
... The advent of nanotechnology has hurtled the discovery and development of nanostructured materials with stellar chemical and physical functionalities in a bid to address issues in energy, environment, telecommunications and healthcare. In this quest, a class of two-dimensional layered materials consisting of alkali or coinage metal atoms sandwiched between slabs exclusively made of transition meta ...
DOI:
10.1039/d0cs00320d

14. How stars are packed in the universe: A comparison with sphere packing

Author:
Wang, C.C.; Dong, K.J.; Zou, R.P.; Yu, A.B.
Source:
Powder technology 2021 v.381 pp. 224-228
ISSN:
0032-5910
Subject:
topology,   etc   ; geometry; lognormal distribution; spatial distribution; technology;     Show all 5 Subjects
Abstract:
... It has been a longstanding question how stars are packed or distributed in the universe. Here we show that the spatial distribution of stars follows some geometric rules although there may be local inhomogeneities. The topological and metric properties of their Voronoi tessellations exhibit a lognormal distribution. Moreover, these distributions can be connected with those established for the pack ...
DOI:
10.1016/j.powtec.2020.12.022

15. Evaluating the Influence of a G-Quadruplex Prone Sequence on the Transactivation Potential by Wild-Type and/or Mutant P53 Family Proteins through a Yeast-Based Functional Assay

Author:
Monti, Paola; Brazda, Vaclav; Bohálová, Natália; Porubiaková, Otília; Menichini, Paola; Speciale, Andrea; Bocciardi, Renata; Inga, Alberto; Fronza, Gilberto
Source:
Genes 2021 v.12 no.2
ISSN:
2073-4425
Subject:
topology,   etc   ; DNA; apoptosis; genes; mutants; transcriptional activation;     Show all 6 Subjects
Abstract:
... P53, P63, and P73 proteins belong to the P53 family of transcription factors, sharing a common gene organization that, from the P1 and P2 promoters, produces two groups of mRNAs encoding proteins with different N-terminal regions; moreover, alternative splicing events at C-terminus further contribute to the generation of multiple isoforms. P53 family proteins can influence a plethora of cellular p ...
DOI:
10.3390/genes12020277

16. Three-Dimensional Triptycene-Based Covalent Organic Frameworks with ceq or acs Topology

Author:
Li, Hui; Chen, Fengqian; Guan, Xinyu; Li, Jiali; Li, Cuiyan; Tang, Bin; Valtchev, Valentin; Yan, Yushan; Qiu, Shilun; Fang, Qianrong
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2654-2659
ISSN:
1520-5126
Subject:
topology,   etc   ; adsorption; carbon dioxide; energy; porosity;     Show all 5 Subjects
Abstract:
... The growth of three-dimensional covalent organic frameworks (3D COFs) with new topologies is still considered as a great challenge due to limited availability of high-connectivity building units. Here we report the design and synthesis of 3D triptycene-based COFs, termed JUC-568 and JUC-569, following the deliberate symmetry-guided design principle. By combining a triangular prism (6-connected) no ...
DOI:
10.1021/jacs.0c12499

17. Role of the pore-opening structure and hydrophobicity of stannosilicate zeolites in Baeyer–Villiger oxidation

Author:
Zhang, Yang; Huo, Yuanling; Tang, Kang; Xu, Wen; Lu, Xinqing; Ma, Rui; Fu, Yanghe; Zhu, Weidong
Source:
Journal of catalysis 2021 v.394 pp. 8-17
ISSN:
0021-9517
Subject:
topology,   etc   ; acidity; catalytic activity; hydrophobicity; oxidation; zeolites;     Show all 6 Subjects
Abstract:
... Although stannosilicate zeolites are active and selective in Baeyer–Villiger (B-V) oxidation because of their unique Lewis acidity, which is useful to activate the carbonyl group of ketone rather than peroxide, the role of their pore-opening structure and hydrophobicity in selective oxidation still needs to be explored. In the present work, stannosilicate zeolites with different topologies were sy ...
DOI:
10.1016/j.jcat.2020.12.003

18. Linker Desymmetrization: Access to a Series of Rare-Earth Tetracarboxylate Frameworks with Eight-Connected Hexanuclear Nodes

Author:
Lv, Xiu-Liang; Feng, Liang; Xie, Lin-Hua; He, Tao; Wu, Wei; Wang, Kun-Yu; Si, Guangrui; Wang, Bin; Li, Jian-Rong; Zhou, Hong-Cai
Source:
Journal of the American Chemical Society 2021 v.143 no.7 pp. 2784-2791
ISSN:
1520-5126
Subject:
topology,   etc   ; catalytic activity; rare earth elements; thermodynamics;     Show all 4 Subjects
Abstract:
... The exploration of metal–organic frameworks (MOFs) through the rational design of building units with specific sizes, geometries, and symmetries is essential for enriching the structural diversity of porous solids for applications including storage, separation, and conversion. However, it is still a challenge to directly synthesize rare-earth (RE) MOFs with less connected clusters as a thermodynam ...
DOI:
10.1021/jacs.0c11546

19. The rise of metal–organic polyhedra

Author:
Lee, Soochan; Jeong, Hyein; Nam, Dongsik; Lah, Myoung Soo; Choe, Wonyoung
Source:
Chemical Society reviews 2021 v.50 no.1 pp. 528-555
ISSN:
1460-4744
Subject:
topology,   etc   ; chemists; classification; coordination polymers; society;     Show all 5 Subjects
Abstract:
... Metal–organic polyhedra are a member of metal–organic materials, and are together with metal–organic frameworks utilized as emerging porous platforms for numerous applications in energy- and bio-related sciences. However, metal–organic polyhedra have been significantly underexplored, unlike their metal–organic framework counterparts. In this review, we will cover the topologies and the classificat ...
DOI:
10.1039/d0cs00443j

20. Topology of additive pairwise effects in food webs

Author:
Móréh, Ágnes; Endrédi, Anett; Piross, Sándor Imre; Jordán, Ferenc
Source:
Ecological modelling 2021 v.440 pp. 109414
ISSN:
0304-3800
Subject:
topology,   etc   ; anthropogenic activities; extinction; food webs;     Show all 4 Subjects
Abstract:
... Contrasting reductionistic versus holistic views, it is a general question whether adding the parts equals the sum. In the time of multiple drivers of anthropogenic change, it is a crucial issue, and better understanding additivity is critical for strategy and management. More particular research questions ask what are the community effects of the extinction of a single species and whether multipl ...
DOI:
10.1016/j.ecolmodel.2020.109414