bluuebunny/crossref_metadata_2025_split huggingface dataset:
Adaptive divergence and post-zygotic barriers to gene flow between sympatric populations of a herbivorous mite
Authors: Villacis-Perez Ernesto , Snoeck Simon , Kurlovs Andre H. , Clark Richard M. , Breeuwer Johannes A. J. , Van Leeuwen Thomas 
Published: July 2021

AbstractPlant-herbivore interactions promote the generation and maintenance of both plant and herbivore biodiversity. The antagonistic interactions between plants and herbivores lead to host race formation: the evolution of herbivore types specializing on different plant species, with restricted gene flow between them. Understanding how ecological specialization promotes host race formation usually depends on artificial approaches, using laboratory experiments on populations associated with agricultural crops. However, evidence on how host races are formed and maintained in a natural setting remains scarce. Here, we take a multidisciplinary approach to understand whether populations of the generalist spider miteTetranychus urticaeform host races in nature. We demonstrate that a host race co-occurs among generalist conspecifics in the dune ecosystem of The Netherlands. Extensive field sampling and genotyping of individuals over three consecutive years showed a clear pattern of host associations. Genome-wide differences between the host race and generalist conspecifics were found using a dense set of SNPs on field-derived iso-female lines and previously sequenced genomes ofT. urticae. Hybridization between lines of the host race and sympatric generalist lines is restricted by post-zygotic breakdown, and selection negatively impacts the survival of generalists on the native host of the host race. Our description of a host race among conspecifics with a larger diet breadth shows how ecological and reproductive isolation aid in maintaining intra-specific variation in sympatry, despite the opportunity for homogenization through gene flow. Our findings highlight the importance of explicitly considering the spatial and temporal scale on which plant-herbivore interactions occur in order to identify herbivore populations associated with different plant species in nature. This system can be used to study the underlying genetic architecture and mechanisms that facilitate the use of a large range of host plant taxa by extreme generalist herbivores. In addition, it offers the chance to investigate the prevalence and mechanisms of ecological specialization in nature.
Diversity of neurovascular coupling dynamics along vascular arbors in layer II/III somatosensory cortex
Authors: Rungta Ravi L. , Zuend Marc , Aydin Ali-Kemal , Martineau Éric , Boido Davide , Weber Bruno , Charpak Serge 
Published: July 2021

AbstractThe spatial-temporal sequence of cerebral blood flow (CBF), cerebral blood volume (CBV) and blood velocity changes triggered by neuronal activation is critical for understanding functional brain imaging. This sequence follows a stereotypic pattern of changes across different zones of the vasculature in the olfactory bulb, the first relay of olfaction. However, in the cerebral cortex, where most human brain mapping studies are performed, the timing of activity evoked vascular events remains controversial. Here we utilized a single whisker stimulation model to map out functional hyperemia along vascular arbours from layer II/III to the surface of primary somatosensory cortex, in anesthetized and awake Thy1-GCaMP6 mice. We demonstrate that sensory stimulation triggers an increase in blood velocity within the mid-capillary bed and a dilation of upstream large capillaries, and the penetrating and pial arterioles. We report that under physiological stimulation, response onset times are highly variable across compartments of different vascular arbours. Furthermore, generating transfer functions (TFs) between neuronal Ca2+ and vascular dynamics across different brain states demonstrates that anesthesia decelerates neurovascular coupling (NVC). This spatial-temporal pattern of vascular events demonstrates functional diversity not only between different brain regions but also at the level of different vascular arbours within supragranular layers of the cerebral cortex.
Ultrastructure of influenza virus ribonucleoprotein complexes during viral RNA synthesis
Authors: Nakano Masahiro , Sugita Yukihiko , Kodera Noriyuki , Miyamoto Sho , Muramoto Yukiko , Wolf Matthias , Noda Takeshi 
Published: July 2021

AbstractThe single-stranded, negative-sense, viral genomic RNA (vRNA) of influenza A virus is encapsidated by viral nucleoproteins (NPs) and an RNA polymerase to form a ribonucleoprotein complex (vRNP) with a helical, rod-shaped structure. The vRNP is responsible for transcription and replication of the vRNA. However, the vRNP conformation during RNA synthesis is not well understood. Here, using high-speed atomic force microscopy and cryo-electron microscopy, we investigated the native structure of influenza A vRNPs during RNA synthesis in vitro. Two distinct types of vRNPs were observed in association with newly synthesized RNAs: an intact, helical rod-shaped vRNP connected with a folded RNA and a deformed vRNP associated with a looped RNA. Interestingly, the looped RNA was a double-stranded RNA, which likely comprises a nascent RNA and the template RNA detached from NPs of the vRNP. These results suggest that while some vRNPs keep their helical structures during RNA synthesis, for the repeated cycle of RNA synthesis, others accidentally become structurally deformed, which likely results in failure to commence or continue RNA synthesis. Thus, our findings provide the ultrastructural feature of vRNPs during RNA synthesis.
Model‐agnostic online forecasting for PV power output
Authors: Lee HyunYong , Lee Jun‐Gi , Kim Nac‐Woo , Lee Byung‐Tak 
Published: July 2021

AbstractA reliable forecasting model is required for photovoltaic (PV) power output because solar energy is highly volatile. Another driver for the need of a reliable forecasting model is concept drift, which means that the statistical properties of the data change over time. In this paper, an online forecasting method to handle concept drift is proposed. First, the problem of forecasting in batch learning is transformed into a forecasting in online learning setting. Then, an online learning algorithm is applied, which is good for handling concept drift. Through experiments using the real‐world data, it is shown that the method noticeably improves performance compared to the case where a trained model is used. Under various concept drift scenarios, the method improves performance by up to 87.3%. It is also shown that the re‐training method (a representative existing method) has several limitations. This method requires several issues to be solved, such as selection of a proper window size, and this is evident through results showing different performance under different settings. In contrast, the method shows a reliable and desirable performance under various concept drift scenarios and thus outperforms the re‐training method. The method improves performance by up to 79%.
Insomnie bei Demenzen
Authors: Mayer Geert , Frohnhofen Helmut 
Published: July 2021

ZUSAMMENFASSUNGSchlafstörungen gehen Demenzen häufig voran und können deren Verlauf verschlimmern. Die Interaktion ist bidirektional. Beide Erkrankungen haben gemeinsame Symptome wie kognitive Einschränkungen und Veränderungen von Schlafstruktur und Qualität. Wenn sich die Demenz einmal manifestiert hat, können Schlafstörungen wie obstruktive Schlafapnoe, Restless-legs-Syndrom und Parasomnien die Symptomatik verstärken. Die Schlafstruktur zeigt eine Verminderung von langsamwelligem Schlaf und häufiges nächtliches Erwachen mit längeren Wachzeiten. Schlaf ermöglicht es, mittels Aktivierung des glymphatischen Systems Aß- und Tau-Proteine, die sich im Wachen angesammelt haben, aus dem ZNS auszuschleusen. Wegen der bidirektionalen Interaktionen ist es erforderlich, Schlafstörungen vermehrte Aufmerksamkeit zu schenken und sie früh zu diagnostizieren und zu behandeln, um einer Verschlimmerung einer existierenden oder sich entwickelnden Demenz vorzubeugen. Eine Anzahl von subjektiven Fragebögen und objektiven Instrumenten wie Polysomnografie und Aktigrafie stehen für die Diagnostik zur Verfügung. Begleitende Schlafstörungen sollten immer mit behandelt werden (z. B. nasale Überdrucktherapie bei Schlafapnoe).Prävention oder Behandlung sollten immer Verhaltenstherapien wie körperliche Aktivierung, soziale Interaktion und ausreichende Exposition gegenüber Tageslicht beinhalten. Einige Antidepressiva, Melatonin, neue duale Orexinrezeptorantagonisten (in Deutschland nicht zugelassen) und wenige Hypnotika können zur Behandlung empfohlen werden. Die Schlafprobleme der betreuenden Personen sollten in den Behandlungsablauf eingeschlossen werden, um die Lebensqualität der Erkrankten zu optimieren.
Is it Possible to Derive the Dresdner Correction Formula Using a Finite Element Program?
Authors: Janknecht Peter 
Published: July 2021

Abstract
Introduction The aim was to construct a model cornea by CAD and finite element software to find out how the intraocular pressure compares to the forces for applanation at the outside
of the model cornea. These data were to be compared to the Dresdner correction formula. Thereby, it was possible to find out whether the model was plausible and to find hints as to why a
correction for how the intraocular pressure depends on the corneal thickness is necessary at all.
Methods Using the open-source software FreeCad and geometrical data for the cornea of the literature, an average cornea was constructed. On this average cornea, a finite element
analysis was performed using the free software z88aurora. The intraocular pressure was measured by applanation of the outer cornea. The necessary forces were analysed.
Results In this model, the intraocular pressure had to be corrected depending on the corneal thickness. The correction factor was kmean; finite
elements = 19.17 – 0.0334*corneal thickness. The necessary correction did not exclusively depend on the relation between the endothelial area and the area of the outer cornea: for this
relation alone the correction would have been karea-relation = 1.0361 – 0.0006*corneal thickness.
Discussion The model correction formula was close to the Dresdner formula. The relation between endothelial area and the area of the outer cornea could only explain about half of the
necessary correction.
REM-Schlafverhaltensstörung
Authors: Heidbreder Anna , Stefani Ambra 
Published: July 2021

ZUSAMMENFASSUNGDie Rapid-Eye-Movement (REM)-Schlafverhaltensstörung (RBD) ist eine Parasomnie, bei der es zu einem unwillkürlichen Ausleben von Trauminhalten während des REM-Schlafes kommt. Die physiologische Muskelatonie während des REM-Schlafes ist aufgehoben. Die Mehrheit (> 90 %) der Patienten mit einer isolierten RBD (iRBD) entwickeln im weiteren Verlauf eine alpha-Synukleinopathie (M. Parkinson, Demenz mit Lewy-Körperchen, Multisystematrophie). Liegt eine RBD vor, führt die Degeneration von Schaltkreisen des Nucleus subcoeruleus, die inhibierend auf die medulläre Formatio reticularis und in die spinalen Vorderhörner einwirken, dazu, dass Bewegungen während des REM-Schlafs möglich werden. Um die Diagnose einer RBD stellen zu können, ist der Nachweis einer fehlenden Muskeltonusabsenkung während des REM-Schlafes (REM-sleep without atonia, RWA) notwendig, was nur mit Hilfe einer Videopolysomnografie möglich ist. Grundvoraussetzung für die Beurteilung von Verhaltensauffälligkeiten und Vokalisationen ist die zeitsynchrone Aufzeichnung von Video und Ton. Kurative oder krankheitsmodulierende Therapien existieren nicht. Groß angelegte Behandlungsstudien, die einen Effekt in der symptomatischen Behandlung nachweisen, liegen ebenfalls nicht vor, sodass Therapieempfehlungen meist auf Expertenmeinungen und Daten retrospektiver Fallserien basieren. Dabei zeigten sich Melatonin 3–12 mg und Clonazepam 0,25–2 mg als wirksam. Da die RBD ein Frühstadium einer neurodegenerativen Erkrankung darstellt, bietet sie sich in der Zukunft als Ausgangspunkt für neuroprotektive Studien an.
1.5 Photochemistry and Radical Generation: Approaches in Mechanism Elucidation
Authors: Cahoon S. B. , Yoon T. P. 
Published: July 2021

AbstractThe development of photocatalytic reactions has reemerged as an active area of research in organic synthesis. A large variety of synthetically valuable transformations have now been developed that take advantage of the ease by which photocatalysts generate a variety of open-shelled reactive intermediates. The study of the mechanisms of these reactions, however, is a challenge, especially in increasingly sophisticated reactions that often involve multiple steps and complex reaction mixtures. Multiple complementary techniques often need to be utilized in tandem in order to develop a detailed understanding of these reactions. The first part of this review outlines many of the most common techniques that are used to interrogate the initiation and product-formation steps of a photocatalytic transformation. The second part describes case studies that provide contextual examples of how photophysical, electrochemical, physical organic, and computational investigations can be used together to provide insights into the mechanisms of complex photocatalytic reactions.
1.12 Intermolecular Radical C—H Functionalization
Authors: Bietti M. , Dénès F. 
Published: July 2021

AbstractThe generation of carbon-centered radicals via intermolecular hydrogen-atom transfer (HAT) from C—H bonds to an abstracting species (HAT reagent) represents a significant challenge in terms of reactivity, site-selectivity and stereoselectivity. The radical species resulting from such a transfer can then engage in carbon—carbon or carbon—heteroatom bond formation, possibly through the intervention of transition-metal catalysts, leading to a variety of functionalized products. This chapter aims to provide the reader with useful guidelines to understand, predict, and design selective radical transformations based upon initial HAT from a C—H bond coupled to different radical-capture strategies. A selection of examples that illustrate different approaches to implement HAT reactions in synthetically useful procedures are presented.
1.13 Intramolecular Hydrogen-Atom Transfer
Authors: Treacy S. M. , Zhang X. , Rovis T. 
Published: July 2021

AbstractRecent advances in intramolecular hydrogen-atom transfer (HAT) have demonstrated significant utility in C—H functionalization through highly reactive open-shell intermediates. The intramolecular transposition of radical reactivity from select functional groups to generate more stable carbon-centered radicals often proceeds with high regioselectivity, providing novel bond disconnections at otherwise inert and largely indistinguishable positions. This chapter explores the functional groups capable of intramolecular HAT to generate remote radicals and the transformations currently available to the synthetic chemist.
Individual variation influences avoidance behaviour of invasive common carp (
Authors: Bzonek Paul A. , Kim Jaewoo , Mandrak Nicholas E. 
Published: July 2021

Uncontrolled biological invasions are reducing freshwater ecosystem diversity and resilience. Research is needed to evaluate whether non-structural deterrents are feasible within lock or canal environments. This study examined common carp (Cyprinus carpio) and buffalo hybrid (Ictiobus) movement patterns in response to acoustic and stroboscopic deterrents. Twelve strobe lights and one underwater speaker were deployed across the centre of a ship slip, with an environment analogous to a navigation canal. Common carp (n = 6) and Ictiobus (n = 4) were implanted with acoustic telemetry tags, and their behaviours were examined under control, stroboscopic, and acoustic stimuli for 60-min trial periods. Trials were run during the day and night for six straight days. Linear models determined that the stroboscopic and acoustic stimuli altered fish positioning within the ship slip, but produced weaker avoidance responses than those observed elsewhere. Weak responses were likely due to a strong preference for the open end of the ship slip and a lack of acoustic refuge during the acoustic treatment. Avoidance responses also differed widely among individuals of the same species, with fish expressing repeatability of avoidance radius size across trials. Ambient and stimulus sound-pressure levels should be carefully considered when deploying acoustic deterrents.
Nonlinear dynamical properties of frequency swept fiber-based semiconductor lasers
Authors: Slepneva Svetlana , Pimenov Alexander 
Published: July 2021

Abstract
We investigate dynamics of semiconductor lasers with fiber-based unidirectional ring cavity that can be used as frequency swept sources. We identify key factors behind the reach dynamical behavior of such lasers using state-of-the-art experimental and analytical methods. Experimentally, we study the laser in static, quasi-static and synchronization regimes. We apply experimental methods such as optical heterodyne or electric field reconstruction in order to characterize these regimes or study the mechanisms of transition between them. Using a delay differential equation model, we demonstrate that the presence of chromatic dispersion can lead to destabilization of the laser modes through modulational instability, which results in undesirable chaotic emission. We characterize the instability threshold both theoretically and experimentally, and demonstrate deterioration of the Fourier domain mode locking regime near the threshold.
X-ray to MR: the progress of flexible instruments for endovascular navigation
Authors: Abdelaziz Mohamed E M K , Tian Libaihe , Hamady Mohamad , Yang Guang-Zhong , Temelkuran Burak 
Published: July 2021

Abstract
Interventional radiology and cardiology are rapidly growing areas of minimally invasive surgery, covering multiple diagnostic and interventional procedures. Treatment via endovascular techniques has become the go-to approach, thanks to its minimally invasive nature and its effectiveness in reducing hospitalisation and total time to recovery when compared to open surgery. Although x-ray fluoroscopy is currently the gold standard imaging technique for endovascular interventions, it presents occupational safety hazards to medical personnel and potential risks to patients, especially paediatric patients, because of its inherent ionising radiation. Magnetic resonance imaging (MRI), with its unique ability to provide radiation-free imaging, and acquiring morphologic and functional information, holds great promise in the advancement of image-guided navigation through the vasculature. Moreover, MRI has the potential to combine diagnosis, therapy and early evaluation of therapy in the same intervention. However, MR-guided interventions face a major challenge due to the presence of a large magnetic field (1.5/3 Tesla), which limits the set of materials suitable for the construction of key instrumentation (sheaths, catheters and guidewires). Despite these challenges, in recent years, significant progress has been made in the development of interventional devices, which comprise biocompatible, MR safe and MR visible materials. In an attempt to encourage and accelerate the development of MR-guided endovascular instrumentation, we present a systematic and illustrated overview of the plethora of work targeting to overcome the aforementioned limitations which are underpinned by the interdependent advancements in science, technology, engineering, mathematics and medicine (STEMM).
Homogenization of hyperbolic equations with periodic coefficients in ℝ^{𝕕}: Sharpness of the results
Authors: Dorodnyi M. , Suslina T. 
Published: July 2021

In

L
2

(

R

d

;

C

n

)

L_2(\mathbb {R}^d;\mathbb {C}^n)

, a selfadjoint strongly elliptic second order differential operator

A

ε

\mathcal {A}_\varepsilon

is considered. It is assumed that the coefficients of

A

ε

\mathcal {A}_\varepsilon

are periodic and depend on

x

/

ε

\mathbf {x}/\varepsilon

, where

ε
>
0

\varepsilon >0

is a small parameter. We find approximations for the operators

cos
⁡
(

A

ε

1

/

2

τ
)

\cos (\mathcal {A}_\varepsilon ^{1/2}\tau )

and

A

ε

−
1

/

2

sin
⁡
(

A

ε

1

/

2

τ
)

\mathcal {A}_\varepsilon ^{-1/2}\sin (\mathcal {A}_\varepsilon ^{1/2}\tau )

in the norm of operators acting from the Sobolev space

H
s

(

R

d

)

H^s(\mathbb {R}^d)

to

L
2

(

R

d

)

L_2(\mathbb {R}^d)

(with suitable

s
s

). We also find approximation with corrector for the operator

A

ε

−
1

/

2

sin
⁡
(

A

ε

1

/

2

τ
)

\mathcal {A}_\varepsilon ^{-1/2}\sin (\mathcal {A}_\varepsilon ^{1/2}\tau )

in the

(

H
s

→

H
1

)

(H^s \to H^1)

-norm. The question about the sharpness of the results with respect to the type of the operator norm and with respect to the dependence of estimates on

τ
\tau

is studied. The results are applied to study the behavior of the solutions of the Cauchy problem for the hyperbolic equation

∂
τ
2

u

ε

=
−

A

ε

u

ε

+

F

\partial _\tau ^2 \mathbf {u}_\varepsilon = -\mathcal {A}_\varepsilon \mathbf {u}_\varepsilon + \mathbf {F}

.
Target enrichment improves phylogenetic resolution in the genus Zanthoxylum (Rutaceae) and indicates both incomplete lineage sorting and hybridization events
Authors: Reichelt Niklas , Wen Jun , Pätzold Claudia , Appelhans Marc S 
Published: July 2021

Abstract

Background and Aims
Zanthoxylum is the only pantropical genus within Rutaceae, with a few species native to temperate eastern Asia and North America. Efforts using Sanger sequencing failed to resolve the backbone phylogeny of Zanthoxylum. In this study, we employed target-enrichment high-throughput sequencing to improve resolution. Gene trees were examined for concordance and sectional classifications of Zanthoxylum were evaluated. Off-target reads were investigated to identify putative single-copy markers for bait refinement, and low-copy markers for evidence of putative hybridization events.

Methods
A custom bait set targeting 354 genes, with a median of 321 bp, was designed for Zanthoxylum and applied to 44 Zanthoxylum species and one Tetradium species as the outgroup. Illumina reads were processed via the HybPhyloMaker pipeline. Phylogenetic inferences were conducted using coalescent and maximum likelihood methods based on concatenated datasets. Concordance was assessed using quartet sampling. Additional phylogenetic analyses were performed on putative single and low-copy genes extracted from off-target reads.

Key Results
Four major clades are supported within Zanthoxylum: the African clade, the Z. asiaticum clade, the Asian–Pacific–Australian clade and the American–eastern Asian clade. While overall support has improved, regions of conflict are similar to those previously observed. Gene tree discordances indicate a hybridization event in the ancestor of the Hawaiian lineage, and incomplete lineage sorting in the American backbone. Off-target putative single-copy genes largely confirm on-target results, and putative low-copy genes provide additional evidence for hybridization in the Hawaiian lineage. Only two of the five sections of Zanthoxylum are resolved as monophyletic.

Conclusions
Target enrichment is suitable for assessing phylogenetic relationships in Zanthoxylum. Our phylogenetic analyses reveal that current sectional classifications need revision. Quartet tree concordance indicates several instances of reticulate evolution. Off-target reads are proven useful to identify additional phylogenetically informative regions for bait refinement or gene tree based approaches.