bluuebunny/crossref_metadata_2025_split huggingface dataset:
Theory of Host–Parasite Coevolution: From Ecology to Genomics
Authors: Tellier Aurélien , Brown James KM , Boots Mike , John Sona 
Published: May 2021

Abstract

Antagonistic coevolution between hosts and parasites is a ubiquitous process in nature. The theory of coevolution describes how reciprocal changes in genotype frequencies occur in the interacting species over time. Host–parasite coevolution is driven by two types of frequency‐dependent selection (FDS): indirect FDS arises from the host–parasite interaction, while direct FDS arises from ecological features which affect coevolution. Depending on the balance between indirect and direct FDS and the strength of stochastic processes in natural populations coevolution, two main outcomes occur: trench warfare dynamics as the long‐term maintenance of genetic and phenotypic diversity and an arms race with ultimate fixation of genotypes in both species. Coevolution is a prime example of eco–evo processes in which there is feedback between short‐term ecological dynamics and the evolutionary dynamics of allele frequencies. With new sequencing technologies, it is possible to reveal how coevolution shapes the genomic diversity and genome evolution of antagonistic species.

Hosts can vary in the specificity of their resistance to parasites, and parasites can vary in the corresponding infectivity.

The specificity of the host–parasite interaction is governed by genes which coevolve.

Hosts can further vary in their quantitative resistance and parasite in their virulence.

These traits and the underlying genotypes change frequency in time due to indirect and direct frequency‐dependent selection (FDS). Indirect FDS arises from the host–parasite interaction, while direct FDS arises from ecological features which affect coevolution.

The balance between these two types of FDS determines the stability of the polymorphism of the coevolving genotypes.

The further role of stochastic processes, such as genetic drift, is to generate either arms race or trench warfare dynamics of gene frequencies.

The costs of resistance and infectivity are necessary to generate coevolutionary cycles in time but not sufficient to promote stable long‐term polymorphism.

Ecological–evolutionary (eco–evo) feedbacks and trade‐offs due to fitness costs can explain the dynamics of coevolution and the stability of coevolutionary outcomes.

The genomes of antagonistic species can be partitioned into major, minor and neutral genes which present different signatures of genetic diversity and can be used to study coevolution based on the theoretical framework described here.
Prokaryotic Systematics: Theoretical Overview in Post‐Genomic Era
Authors: Kurtböke Ipek 
Published: May 2021

AbstractSystematics describes the ordering of information on organisms and plays an important role in communicating information within biological sciences. Systematics seeks to reveal the phenotypic and genotypic diversity of organisms while relating this information to natural interactions and evolutionary history. Systematics may utilise a wide range of data and is not limited to the experimental methods that it may draw on in order to make sensible comparisons between organisms. Systematics links phylogeny with taxonomy. Taxonomy involves characterisation, naming and classification of organisms according to defined criteria. Systematics requires an underlying order, and both systematics and taxonomy are strongly dependent on theory and philosophy, which are used to create this order. Systematics is a complex area, which has seen much change and progress in the past century as well as in the past few decades as a result of the molecular advances. Developments in molecular biology have been adapted in line with the theory and philosophy and have become established in systematics. In the molecular era, phylogenetic and taxogenomic methods are the driving forces behind the revalidation of currently used theories and hypotheses formulated for systematics.Systematics is the study of the diversity of organisms and their relationship.Classification involves ordering of microorganisms into groups/taxa based on their interrelationships.Taxonomy is the theory and practice of identifying, describing, naming and classifying organisms.Nomenclature is the science of defining and naming taxonomic categories such as the species, genera, families, orders, classes, phyla and domains.Nomenclature of prokaryotes is governed by the rules of the Prokaryotic Code (International code of Nomenclature of Prokaryotes, as determined by theInternational Committee on Systematics of Prokaryoteshttps://www.the‐icsp.org/.Species are the fundamental units of biological diversity, and all members of a species should carry distinct traits.Current systematists make extensive use of molecular biology and bioinformatics to study microorganisms.The basis of molecular phylogeny refers to evolutive relationship of microorganisms that can be inferred from the relationships of their genes and their genomes.Genomics explores the biology of organisms through their genetic blueprints.Metagenomics provides access to genome for prediction of ecological roles of the members of microbial communities, revealing the metabolic and functional diversity of microorganisms in natural environments.
Microsatellite Instability
Authors: Schlötterer Christian 
Published: May 2021

AbstractMicrosatellites, also called short tandem repeats (STR) or simple sequence repeats (SSR), are short tandemly repeated sequence motifs of 1–6 bp. They have a proprietary mutation mechanism, DNA replication slippage, which results in the gain or loss of repeat units. Because microsatellites experience a higher mutation rate than single‐copy DNA and their alleles can be easily scored without DNA sequencing, microsatellites have been a highly popular genetic marker for forensics, behavioural ecology, population and conservation genetics. Many human genetic disorders were identified by genetic mapping with microsatellites. Exceptionally long microsatellites have been found to be associated with certain human genetic disorders, such as Huntington disease, fragile X and spinocerebellar ataxia.Microsatellites are highly variable DNA stretches which mutate by changing their repeat numbers.Microsatellite polymorphisms are generated by a specific mutation process called DNA replication slippage.Microsatellites are distributed throughout the entire genome.Specific microsatellite loci are conserved across species boundaries, but ultimately they degenerate by the acquisition of base substitutions.Trinucleotide repeats are often involved in genetic disorders which can be attributed to the expansion of a trinucleotide repeat.Most simple genetic disorders in humans were mapped using polymorphic microsatellites as genetic markers.Microsatellites were highly versatile genetic markers, which allowed unprecedented insights into many research areas, such as population genetics, forensics, behavioural ecology and molecular ecology.
Extinction: End‐Permian Mass Extinction
Authors: Clapham Matthew E 
Published: May 2021

Abstract

The end‐Permian mass extinction (251.9 million years ago) was an abrupt and severe loss of diversity on land and in the oceans, the largest extinction of the Phanerozoic. Recent palaeontological, geochemical and modelling studies link the extinction with eruption of the Siberian Traps flood basalts, which would have caused ocean warming and acidification, and shallow‐marine anoxia. On land, global warming, punctuated with episodic cooling from eruption‐related sulfur aerosols, and aridification were mostly responsible for the vertebrate and plant extinction. Although almost no marine group emerged unscathed, selectivity favoured more active animals, while sessile and heavily calcified taxa such as corals and reef‐building sponges suffered heavily. The recovery interval was unusually long, likely because of continuing stress, and the extinction resulted in permanent shifts in marine ecosystem composition and structure, giving rise to the mollusc‐rich communities that still dominate today.

The end‐Permian mass extinction was a severe crisis for nearly every plant and animal group, on land and in the oceans.

The extinction was abrupt, apparently synchronous on land and in the sea in the tropics (but perhaps earlier among high‐latitude plants), with the majority of taxonomic losses occurring over a few tens of thousands of years, approximately 251.9 million years ago.

In the marine realm, more actively motile animal groups fared relatively better during the extinction. Reef ecosystems were particularly hard‐hit.

The primary causes of the marine extinction were ocean warming, acidification and expansion of low‐oxygen water, ultimately triggered by CO
2
released by Siberia Traps flood basalt volcanism.

The terrestrial extinction was also caused by global warming and the resulting dry conditions and perhaps acid rain or ozone destruction and enhanced UV radiation.

It took an unusually long time (5–7 million years) for most marine and terrestrial ecosystems to recover from the extinction, likely because of continuing intermittent stress.

The extinction triggered permanent changes in the composition and structure of marine ecosystems, giving rise to mollusc‐dominated communities that remain dominant today.
Cyanogenic Glycosides and Biogenetically Related Compounds in Higher Plants and Animals
Authors: Lechtenberg Matthias 
Published: May 2021

AbstractCyanogenesis describes the ability of living organisms to liberate hydrogen cyanide from stored cyanogenic glycosides upon tissue damage by hydrolysis and/or decomposition. It has been described for more than 3000 species of higher plants. Chemically, cyanogenic glycosides are glycosides of α‐hydroxynitriles (cyanohydrins). Cyanogenic glycosides together with plant glycosidases and hydroxynitrile lyases form a preformed defence system. The structures are biogenetically related to only a few precursor amino acids. In the biosynthetic pathway, two multifunctional P450 enzymes and a glucosyltransferase act in a sequence. Biogenetically, glucosides of β‐ and γ‐hydroxynitriles are closely related.Cyanogenic glycosides and their related nitriles also may serve as storage forms for reduced nitrogen. A recycling pathway has been proposed to recover reduced nitrogen for primary metabolism. Many food plants are cyanogenic, and great efforts are made to optimise their detoxification. The presence of cyanogenic glycosides in the animal kingdom appears to be restricted to arthropods. Some insects, often aposematically coloured, synthesise cyanogenic glycosidesde novoand/or sequester them from their host plants.Cyanogenic glycosides are secondary metabolites known from more than 3000 different higher plant species.Cyanogenic plants are able to liberate hydrogen cyanide from their cyanogenic glycosides upon disruption of plant tissue.Cyanogenic glycosides and their corresponding degrading enzymes are part of a preformed defence system. Thus, they can be regarded as phytoanticipins.Cyanogenic glycosides are glycosides of α‐hydroxynitriles, derived from five proteinogenic amino acids (Phe, Tyr, Val, Ile and Leu) and from the nonproteinogenic amino acid cyclopentenyl glycine. Acalyphin is apparently derived from nicotinic acid.A biogenetically related class consists of β‐ and γ‐hydroxynitrile glucosides, apparently derived from the aliphatic amino acids (Val, Ile and Leu).Up to now more than 100 different glycosylated α‐, β‐ and γ‐hydroxynitriles are known from higher plants and arthropods.Additional roles and functions of cyanogenic glycosides include storage of reduced nitrogen, transportation of nitrogen and the turnover of nitrogen into primary metabolism.The presence of cyanogenic glycosides in animals appears to be restricted to arthropods.Some insects are strongly associated with their cyanogenic host plants. They sequester the cyanogenic glycosides from these plants and additionally carry outde novobiosynthesis of these compounds.Convergent evolution in plants and insects has resulted in two identical biosynthesis pathways: two multifunctional P450 enzymes and a glucosyltransferase, acting sequentially.
Osmoregulation by Vertebrates in Terrestrial Environments
Authors: Hillman Stanley S 
Published: May 2021

Abstract

A terrestrial environment for vertebrates leads to both a passive water loss to the air and solute gain through food. Consequently, terrestrial environments would tend to decrease water content and increase the osmotic concentration of vertebrates. Natural selection has led to a variety of behavioural, physiological and anatomical adaptations to both minimise water loss and excrete solutes in order to maintain a constant osmotic concentration in terrestrial environments. Extant amphibians represent the ancestral colonisers of terrestrial environments. Their water‐permeable skin make them most prone to dehydration and have the greatest tolerance to dehydration and the most unique mechanisms to stabilise plasma volume with dehydration. Reptiles exploit very arid terrestrial environments by minimising cutaneous evaporative water loss. Birds and mammals have unique kidney capacities to concentrate solutes and minimise urinary water loss. This in conjunction with elaborate nasal turbinates to minimise respiratory water loss allows them to survive in arid terrestrial environments.

Terrestrial environments favour water loss and challenge maintenance of body water volume and osmotic concentration.

Water budgets and daily rates of water turnover are constructed to quantify avenues of exchange and propensity for water stress.

Extant amphibians represent the ancestral group of vertebrates that colonised terrestrial environments.

Amphibians have the greatest rates of daily water turnover, primarily a consequence of high rates of evaporative water loss resulting from high cutaneous permeability to water.

Reptiles have the lowest rates of daily water turnover, primarily the result of low rates of cutaneous evaporative water loss.

Endothermic classes (birds and mammals) have intermediate daily water turnover rates, the result of metabolic water production with their elevated aerobic metabolic rates.

Endothermic classes can minimise urinary losses and better able stabilise osmotic concentrations the result of kidneys that can produce urine hyperosmotic to their own body fluid concentration.

The threat of dehydration is greatest for amphibians, given the high daily water turnover rates.

Dehydrational stress is handled by amphibians and some reptiles by first reabsorbing stored hypoosmotic urine from their urinary bladders.

When stored bladder fluid is exhausted, the key element to handling dehydration is maintaining plasma volume at the expense of intracellular water and interstitial fluid.

Anuran amphibians have the greatest capacity to maintain cardiac function with dehydration.
Artificial Intelligence of Things (AIoT) Enabled Virtual Shop Applications Using Self‐Powered Sensor Enhanced Soft Robotic Manipulator
Authors: Sun Zhongda , Zhu Minglu , Zhang Zixuan , Chen Zhaocong , Shi Qiongfeng , Shan Xuechuan , Yeow Raye Chen Hua , Lee Chengkuo 
Published: May 2021

AbstractRapid advancements of artificial intelligence of things (AIoT) technology pave the way for developing a digital‐twin‐based remote interactive system for advanced robotic‐enabled industrial automation and virtual shopping. The embedded multifunctional perception system is urged for better interaction and user experience. To realize such a system, a smart soft robotic manipulator is presented that consists of a triboelectric nanogenerator tactile (T‐TENG) and length (L‐TENG) sensor, as well as a poly(vinylidene fluoride) (PVDF) pyroelectric temperature sensor. With the aid of machine learning (ML) for data processing, the fusion of the T‐TENG and L‐TENG sensors can realize the automatic recognition of the grasped objects with the accuracy of 97.143% for 28 different shapes of objects, while the temperature distribution can also be obtained through the pyroelectric sensor. By leveraging the IoT and artificial intelligence (AI) analytics, a digital‐twin‐based virtual shop is successfully implemented to provide the users with real‐time feedback about the details of the product. In general, by offering a more immersive experience in human–machine interactions, the proposed remote interactive system shows the great potential of being the advanced human–machine interface for the applications of the unmanned working space.
Neutral Unsymmetrical Coordinated Cyclophane Polymerization Catalysts
Authors: Schiebel Eva , Voccia Maria , Falivene Laura , Göttker‐Schnetmann Inigo , Caporaso Lucia , Mecking Stefan 
Published: May 2021

AbstractCyclophane structures can control steric pressure in the otherwise open spaces of square‐planar d8‐metal catalysts. This elegant concept was so far limited to symmetrical coordinated metals. We report how a cyclophane motif can be generated in ligands that chelate via two different donors. An ancillary second imine in the versatile κ2‐N,O‐salicylaldiminato catalyst type enables ring closure via olefin metathesis and selective double bond hydrogenation to yield a 30‐membered ring efficiently. Experimental and theoretical analyses show the ancillary imine is directed away from the active site and inert for catalysis. In ethylene polymerization the cyclophane catalyst is more active and temperature stable vs. an open structure reference, notably also in polar solvents. Increased molecular weights and decreased degrees of branching can be traced to an increased energy of sterically demanding transition states by the encircling cyclophane while chain propagation remains highly efficient.
Hierarchical Superstructures by Combining Crystallization‐Driven and Molecular Self‐Assembly
Authors: Frank Andreas , Hils Christian , Weber Melina , Kreger Klaus , Schmalz Holger , Schmidt Hans‐Werner 
Published: May 2021

AbstractCombining the unique corona structure of worm‐like patchy micelles immobilized on a polymer fiber with the molecular self‐assembly of 1,3,5‐benzenetricarboxamides (BTAs) leads to hierarchical superstructures with a fir‐tree‐like morphology. For this purpose, worm‐like patchy micelles bearing pendant, functional tertiary amino groups in one of the corona patches were prepared by crystallization‐driven self‐assembly and immobilized on a supporting polystyrene fiber by coaxial electrospinning. The obtained patchy fibers were then immersed in an aqueous solution of a tertiary amino‐functionalized BTA to induce patch‐mediated molecular self‐assembly to well‐defined fir‐tree‐like superstructures upon solvent evaporation. Interestingly, defined superstructures are obtained only if the pendant functional groups in the surface patches match with the peripheral substituents of the BTA, which is attributed to a local increase in BTA concentration at the polymer fibers’ surface.
Platinum‐Templated Coupling of B=N Units: Synthesis of BNBN Analogues of 1,3‐Dienes and a Butatriene
Authors: Brunecker Carina , Arrowsmith Merle , Fantuzzi Felipe , Braunschweig Holger 
Published: May 2021

AbstractThe 1:2 reaction of [μ‐(dmpm)Pt(nbe)]2 (dmpm=bis(dimethylphosphino)methane, nbe=norbornene) with Cl2BNR(SiMe3) (R=tBu, SiMe3) yields unsymmetrical (N‐aminoboryl)aminoboryl PtI2 complexes by B−N coupling via ClSiMe3 elimination. A subsequent intramolecular ClSiMe3 elimination from the tBu‐derivative leads to cyclization of the BNBN unit, forming a unique 1,3,2,4‐diazadiboretidin‐2‐yl ligand. In contrast, the analogous reaction with Br2BN(SiMe3)2 leads, via a twofold BrSiMe3 elimination, to a PtII2 A‐frame complex bridged by a linear BNBN isostere of butatriene. Structural and computational data confirm π electron delocalization over the entire BNBN unit.
Based on transalkylation reaction the rearrangeable conventional sulfur network facile design for vulcanized diolefin elastomers
Authors: Xu Wen‐Zhe , Yu Wei‐Wei , Chen Xu , Liao Shuangquan , Luo Ming‐Chao 
Published: May 2021

AbstractAchieving the reversibility of conventional sulfur crosslinking network is beneficial for the sustainability of rubber products. However, sulfur crosslinking network has been considered as an irreversible network. Here, natural rubber (NR) is chosen as an example and trimethylsulfonium iodide (TMSI) can enable the transalkylation reaction between aliphatic sulfonium salts and the alkyl chains of vulcanized NR, which further realizes the rearrangements of sulfur crosslinking network in the elastomers. Such rearrangement reaction enhances the interfacial adhesion and fuse the fractured surface of vulcanized NR. Moreover, the rearrangements of sulfur crosslinking network induced by TMSI conforms to the characteristics of vitrimer network. This work solves the rearrangement problem of conventional sulfur crosslinking network, which is beneficial for the sustainability of rubber products.
A taxonomy, data set, and benchmark for detecting and classifying malevolent dialogue responses
Authors: Zhang Yangjun , Ren Pengjie , de Rijke Maarten 
Published: May 2021

AbstractConversational interfaces are increasingly popular as a way of connecting people to information. With the increased generative capacity of corpus‐based conversational agents comes the need to classify and filter out malevolent responses that are inappropriate in terms of content and dialogue acts. Previous studies on the topic of detecting and classifying inappropriate content are mostly focused on a specific category of malevolence or on single sentences instead of an entire dialogue. We make three contributions to advance research on the malevolent dialogue response detection and classification (MDRDC) task. First, we define the task and present a hierarchical malevolent dialogue taxonomy. Second, we create a labeled multiturn dialogue data set and formulate the MDRDC task as a hierarchical classification task. Last, we apply state‐of‐the‐art text classification methods to the MDRDC task, and report on experiments aimed at assessing the performance of these approaches.
Selective Imaging of HClO in the Liver Tissue In Vivo Using a Near‐infrared Hepatocyte‐specific Fluorescent Probe
Authors: Jia Xu , Wei Chao , Li Zimeng , Liu Liyan , Wang Mei , Zhang Pingzhu , Li Xiaoliu 
Published: May 2021

AbstractLiver injury is typified by an inflammatory response. Hypochlorous acid (HClO), an important endogenous reactive oxygen species, is regarded as a biomarker associated with liver injury. Near‐infrared (NIR) fluorescent probes with the advantage of deep tissue penetrating and low auto‐fluorescence interference are more suitable for bioimaging in vivo. Thus, in this work, we designed and synthesized a novel NIR hepatocyte‐specific fluorescent probe named NHF. The probe NHF showed fast response (<3 s), large spectral variation, and good selectivity to trace HClO in buffer solution. By employing N‐acetylgalactosamine (GalNAc) as the targeting ligand, probe NHF can be actively delivered to the liver tissue of zebrafish and mice. It is important that probe NHF is the first NIR hepatocyte‐specific fluorescent probe, which successfully visualized the up‐regulation of endogenous HClO in the oxygen‐glucose deprivation/reperfusion (OGD/R) model HepG2 cells and dynamically monitored APAP‐induced endogenous HClO in the liver tissue of zebrafish and mice.