bluuebunny/crossref_metadata_2025 huggingface dataset:
Tree growth responses to different environmental conditions
Authors: Κιοραποστόλου Νατάσα
Published: December 2021

Η αυξανόμενη συχνότητα και ένταση των ξηρασιών επηρεάζει τα δασικά οικοσυστήματα. Ήδη έχουν παρατηρηθεί υψηλότερα ποσοστά θνησιμότητας και φθοράς των δέντρων που προκαλούνται από την ξηρασία. Δεδομένου ότι η κλιματική αλλαγή επηρεάζει τις συνθήκες του εδάφους, τους ρυθμούς βροχοπτώσεων και τις αναπτυξιακές περιόδους, αναμένεται ότι τα δέντρα θα αναπτύξουν στρατηγικές εγκλιματισμού και προσαρμογής προκειμένου να διατηρήσουν τη ζωτικότητά τους. Δεδομένου ότι οι δύο πιο σημαντικοί λόγοι θνησιμότητας είναι η έλλειψη άνθρακα και η υδραυλική αστοχία, οι προσαρμογές στα φυσιολογικά χαρακτηριστικά αναμένεται να σχετίζονται με τη διατήρηση των ισορροπιών άνθρακα και νερού του δέντρου. Η συγκεκριμένη διατριβή επικεντρώθηκε στην κατανόηση του πώς αντιδρούν τα δέντρα κάτω από διαφορετικές περιβαλλοντικές συνθήκες (π.χ. υγρό έναντι ξηρού περιβάλλοντος) τόσο μεταξύ ειδών όσο και σύγκριση του ίδιου είδους. Οι μελέτες που διεξήχθησαν επικεντρώθηκαν στην κατανομή βιομάζας, στην ανατομία του ξυλώματος και του φλοιώματος του κορμού και των κλαδιών, στην ανατομία του ξυλώματος των φύλλων, στην υδραυλική των φυτών και στην πυκνότητα του ξύλου. Κυρίως χρησιμοποιήθηκαν δεδομένα από προσωπικές μετρήσεις, αλλά και δημοσιευμένα δεδομένα για τη σύγκριση των αποτελεσμάτων. Ο στόχος ήταν να κατανοηθεί ποια δομικά χαρακτηριστικά συνδέονται με τις στρατηγικές εγκλιματισμού και προσαρμογής των δέντρων και πώς. Η δομή της διατριβής είναι: (i) γενική εισαγωγή, (ii) πέντε κύρια κεφάλαια που βασίζονται σε διαφορετικές μελέτες, (iii) ένα κύριο κεφάλαιο που περιγράφει εν συντομία τρεις ακόμη μελέτες, (iv) συνολικό συμπέρασμα, (v) πρόσθετες πληροφορίες για κάθε ένα των κύριων κεφαλαίων (εάν υπάρχουν), (vi) ευχαριστίες, (vii) εικόνες ανατομίας για ορισμένα κεφάλαια, (viii) λίστα βιβλιογραφίας ανά κεφάλαιο.
Η ικανοποίηση των διευθυντών σχολικών μονάδων Πρωτοβάθμιας και Δευτεροβάθμιας εκπαίδευσης σχετικά με την επάρκεια χρηματοδότησης των λειτουργικών δαπανών και συντήρησης των εγκαταστάσεων και των υποδομών των σχολείων
Authors: Αργυροπούλου Ελευθερία , Γκαραβέλλας Εμμανουήλ , Λιντζεράκου Ελισσάβετ
Published: December 2021

Σκοπός της παρούσας εργασίας είναι να διερευνήσει την ικανοποίηση των διευθυντών των σχολικών μονάδων Πρωτοβάθμιας και Δευτεροβάθμιας Εκπαίδευσης σχετικά με τη χρηματοδότηση των λειτουργικών αναγκών και δευτερευόντως με τη συντήρηση των εγκαταστάσεων και των υλικοτεχνικών υποδομών των σχολικών μονάδων, όπως αυτή διαμορφώθηκε μετά την επιβολή των οικονομικών μέτρων για την ανάκαμψη της χώρας από την πρόσφατη οικονομική κρίση. Για τη διερεύνηση υιοθετήθηκε η ποσοτική μεθοδολογία. Το δείγμα της έρευνας αποτέλεσαν 852 διευθυντές Πρωτοβάθμιας και Δευτεροβάθμιας Εκπαίδευσης από όλη τη χώρα. Τα αποτελέσματα της έρευνας κατέδειξαν ότι ο βαθμός ικανοποίησης των διευθυντών –προϊσταμένων είναι μέτριος έως χαμηλός, αφού τα κονδύλια που διατέθηκαν ήταν ικανά να καλύψουν μόνον ένα μέρος των επειγουσών αναγκών λειτουργίας. Η σημασία της έρευνάς μας έγκειται στο γεγονός ότι προσπορίζει πρόσφατα και επίκαιρα στοιχεία από το πεδίο και αποπειράται να τεκμηριώσει με αυτά την μέχρι τώρα θρυλούμενη υποχρηματοδότηση των σχολικών μονάδων.
Cognitive Universal Educational Actions of Primary Schoolchildren: Characteristics, Methods and Techniques of Formation
Authors: Romaeva N. , Astrecova N.
Published: December 2021

The article discusses the actual problem of the formation of cognitive universal educational actions in younger schoolchildren in the context of

the implementation of the changing requirements of the Federal State Educational Standard of Primary General Education. The approaches

to the definition of concepts, groups and main characteristics of cognitive universal educational actions that students must master at the first

stage of school education are analyzed. The effective methods and techniques for the formation of this type of educational actions in younger

schoolchildren are presented.
On the group velocity of whistling atmospherics
Authors: Guglielmi Anatol , Klain Boris , Potapov Alexander
Published: December 2021

The dynamic spectrum of a whistling atmospheric is a signal of falling tone, and the group delay time of the signal as a function of frequency is formed as a result of propagation of a broadband pulse in a medium (magnetospheric plasma) with a quadratic dispersion law. In this paper, we show that for quadratic dispersion the group velocity is invariant under Galilean transformations. This means that, contrary to expectations, the group velocity is paradoxically independent of the velocity of the medium relative to the observer. A general invariance condition is found in the form of a differential equation. To explain the paradox, we introduce the concept of the dynamic spectrum of Green’s function of the path of propagation of electromagnetic waves from a pulse source (lightning discharge in the case of a whistling atmospheric) in a dispersive medium. We emphasize the importance of taking into account the motion of plasma in the experimental and theoretical study of electromagnetic wave phenomena in near-Earth space.
The Introduction of Admission Fees in London: Fencing Prizes, Bearbaiting Arenas, and Speculative Origins
Authors: Gerland III Oliver W.
Published: December 2021

Medieval performers gathered coins during a show from people assembled to see them. By 1570, performers throughout London collected admission fees before a show as a condition of entry. When, how, and by whom were admission fees introduced? Based on the research of David Kathman, I argue that travelling players brought the admission fee system to London in the late 1530s, after which animal baiting entrepreneurs and the fencing brotherhood adopted and refined it. In conclusion, this essay offers a speculative origin for the admission fee system in the practice of shrine keeping.
Wideband SiN pulse interleaver for optically-enabled analog-to-digital conversion: a device-to-system analysis with cyclic equalization
Authors: Zazzi Andrea , Müller Juliana , Ghannam Ibrahim , Battermann Moritz , Rajeswari Gayatri Vasudevan , Weizel Maxim , Scheytt J. Christoph , Witzens Jeremy
Published: December 2021

We present the design and experimental characterization of a silicon nitride pulse interleaver based on coupled resonator optical waveguide filters. In order to achieve a targeted free spectral range of 1.44 THz, which is large given the reduced optical confinement of the silicon nitride platform, individual ring resonators are designed with tapered waveguides. Its application to time-interleaved photonically-assisted ADCs is analyzed by combining experimental characterization of the photonic integrated circuit with a comprehensive model of the entire ADC. The impact of fundamental signal distortion and noise sources affecting the converter is investigated and suitable equalization techniques at the digital signal processing level are evaluated. The novel application of a simple but powerful equalization filter in the DSP domain allows for a significant improvement of the digitized signal SNR. An ENOB of 5 over a 75 GHz bandwidth (150 GS/s) and an ENOB of 4.3 over a 100 GHz bandwidth (200 GS/s) are expected to be achievable with compact and off-the-shelf single-section semiconductor mode locked lasers, that can be further improved with lower noise light sources.
Bending induced output power concentration in a core of a 4-core Yb-doped fiber laser
Authors: Wolf Alexey A. , Skvortsov Mikhail I. , Lobach Ivan A. , Dostovalov Alexandr V. , Babin Sergey A.
Published: December 2021

An all-fiber 4-core Yb-doped laser with a cavity formed by fiber Bragg gratings directly inscribed in each core with femtosecond laser pulses and 4% Fresnel reflection from the output fiber end face is demonstrated. It has been shown that the diameter of the active fiber winding significantly affects the power distribution between the cores, since it affects both the pump power distribution and the cross-coupling between the cores. In particular, with an active fiber winding diameter of 21 cm, the cores behave independently, and the power is distributed almost evenly over all cores. With a winding diameter of 6.5 cm, the lasing is achieved almost exclusively from one core, and a mechanism of that radiation concentration based on bending induced stress in an active multicore fiber is proposed which explains the experimental data. By analyzing the optical and radio-frequency spectra of the output laser radiation, additional details of the 4-core fiber lasing are revealed. In particular, a narrowband (several longitudinal modes) lasing with periodic linear sweeping of central wavelength in time is observed and characterized in the multicore fiber laser, for the first time to our knowledge. It is shown that crosstalk of longitudinal modes arising from different cores is greatly enhanced in the case of a strongly bent fiber.
Simulating electrical fields in the orbital angular momentum space of light
Authors: Zhu Chen-Xi , Zhou Xingxiang , Guo Guang-Can , Zhou Zheng-Wei
Published: December 2021

We study a system of coupled degenerate cavities with a switchable beam rotator embedded in the optical path of the main cavity. By exploiting the phase shift of the beam rotator dependent on the orbital angular momentum of the optical modes, and modulating the phase imbalance in the auxiliary cavity, it is shown that the system dynamics is equivalent to that of a charged particle in a 1D lattice subject to both static and time-dependent electrical fields. We investigate interesting physics and phenomena such as Bloch oscillations that arise due to the simulated electrical fields, and discuss how they can be used for practical purposes such as storing optical signals in a quantum memory. We also present a powerful measurement scheme to detect the system dynamics that is non-intrusive and technically easy to perform.
Single-mode suspended large-core chalcohalide fiber with a low zero-dispersion wavelength for supercontinuum generation
Authors: Jiao Kai , Wang Xian-Ge , Liang Xiaolin , Bai Shengchuang , Zhao Zheming , Wang Xunsi , Zhang Peiqing , Dai Shixun , Nie Qiuhua , Wang Rongping
Published: December 2021

Chalcogenide glass possesses outstanding advantages, such as supercontinuum generation, but its nonlinear applications were limited by large zero-dispersion wavelength (ZDW). Traditional suspended-core fibers can shift the ZDW to near IR with a tiny core size of less than 5 µm but a large evanescent wave loss exists in these fibers. In this paper, we prepared a novel suspended-core fiber (SCF) based on chalcohalide glasses for the first time via the extrusion method, in which the ZDW of the fundamental mode in the fiber with a core size of larger than 30 µm was successfully shifted to 2.6 µm. We also calculated confinement loss (CL) of propagation modes and fundamental mode energy ratio in the fiber. We found that the minimum CL ratio of the high order modes (LP11) to the CL of the fundamental mode is 124, indicating that the single-mode operation condition is satisfied when the wavelength is more than 4.6 µm. The lowest transmission loss is 1.2 dB/m at 6.5 µm. An ultra-broad supercontinuum spectrum, covering from 1.6 to 12 µm was generated in this suspended-core fiber pumped by a 5 µm femtosecond laser. Such a wide SC in the chalcogenide SCF is due to the large core size. All these results demonstrate the potential to use the large core SCF in the application of a mid-IR laser.
2.1 μm, 1.52 μJ square-wave noise-like pulse from an all-fiber figure-of-9 Ho-doped oscillator and single-stage amplifier
Authors: Zhao Desheng , Zhang Bin , Zhu Xiran , Liu Shuailin , Yang Linyong , Hou Jing
Published: December 2021

A 2.1 μm, high energy square-wave noise-like pulse (NLP) in an all-fiber Ho-doped fiber laser is proposed, which consists of an oscillator and a single-stage amplifier. In the figure-of-9 oscillator, mode-locking is achieved based on the nonlinear amplifying loop mirror, employing a long gain fiber to provide sufficient gain in 2.1 μm band and optimizing the cavity length to obtain maximum pulse energy output. With appropriate pump power and polarization state, the oscillator emits a 175.1 nJ square-wave NLP with center wavelength of 2102.2 nm and spike width of 540 fs. The 3-dB spectral width and pulse envelope width are 11.2 nm and 6.95 ns, respectively. The single-stage amplifier employs a bi-directional pump scheme. After amplification, 5.8 W NLP with a slope efficiency of 56.8% is obtained. The pulse energy of NLP is scaled to 1.52 μJ, which is the highest pulse energy of NLP at 2.1 μm to the best of our knowledge. The obtained high-energy square-wave NLP-fiber laser has great potential in mid-infrared laser generation.
Cavity enhanced parametric homodyne detection of a squeezed quantum comb
Authors: Tian Yuhang , Sun Xiaocong , Wang Yajun , Li Qinghui , Tian Long , Zheng Yaohui
Published: December 2021

A squeezed state with higher-order sidebands is a valuable quantum resource for channel multiplexing quantum communication. However, balanced homodyne detection used in nonclassical light detection has a trade-off performance between the detection bandwidth and clearance, in which the verification of a highly squeezing factor faces a challenge. Here, we construct two optical parametric amplifiers with cavity enhancement; one is for the generation of a −10.5 dB squeezed vacuum state, and the other is for all-optical phase-sensitive parametric homodyne detection. Finally, −6.5 dB squeezing at the carrier with 17 pairs of squeezing sidebands (bandwidth of 156 GHz) is directly and simultaneously observed. In particular, for the cavity-enhanced parametric oscillation and detection processes, we analyze the limiting factors of the detectable bandwidth and measurement deviation from the generated value, which indicates that the length difference and propagation loss between two optical parametric amplifiers should be as small as possible to improve the detection performance. The experimental results confirm our theoretical analysis.
Variable-focus liquid lens based on electrically responsive fluid
Authors: Xu Miao , Liu Yating , Yuan Ye , Lu Hongbo , Qiu Longzhen
Published: December 2021

In this work, an adaptive liquid lens using a novel transparent electrically responsive fluid, dibutyl adipate (DBA), is demonstrated. The DBA liquid lens with a hemispherical plano-convex shape can change its curvature according to the application of various input voltages. More specifically, when an external direct current (DC) electric field is applied to the DBA liquid, the charges that are injected from the cathode move along with the DBA molecules toward the anode and accumulate on the surface of the anode. When the DC electric field is removed, the shape of the DBA liquid is recovered to its original state. This electrostatic force induces the deformation of the DBA liquid lens within a concentric annular anode electrode. In addition, the focal length of our system is increased from a value of approximately 7.5 mm to 13.1 mm when the voltage is changed from 0 to 100 V. Interestingly, the resolution of our DBA liquid lens can reach a value of ∼28.5 lp/mm. The proposed DBA liquid lens exhibits high optical transmittance (∼95%), good thermal stability (20–100°C), simple structure, and an excellent imaging property, which implies that the DBA liquid is a promising candidate for fabricating novel adaptive liquid lenses.
W-band simultaneous vector signal generation and radar detection based on photonic frequency quadrupling
Authors: Wang Yanyi , Ding Junjie , Wang Mingxu , Dong Ze , Zhao Feng , Yu Jianjun
Published: December 2021

In this paper, we propose and experiment with a dual-functional system that can simultaneously implement vector signal generation and radar detection based on frequency quadrupling. In the experimental demonstration, a generated W-band quadrature-phase-shift-keying (QPSK) vector signal is transmitted wirelessly over 1 m with a bit-error rate (BER) below 3.8 × 10−3. A radar working in the W band is investigated with a range resolution of 0.94 cm. To the best of our knowledge, this is the first time that simultaneous QPSK vector signal generation and radar detection in the W band has been realized.
Optical element to generate zero-order quasi-Bessel beam with “focal length”
Authors: Zhang Mengting , Liu Wei , Huang Qian , Han Meiyao , Xiang Feidi , Yang Zhengang , Liu Jinsong , Wang Kejia
Published: December 2021

An optical element has been invented to generate a zero-order quasi-Bessel beam with a certain distance to the element, which does not exist in the zero-order quasi-Bessel beam by using a traditional axicon. The cross section of designed element is an isosceles triangle whose equal sides are circumscribed by two semi-ellipses. Using a well-developed three-dimensional (3D)-printing technique, we have fabricated a series of elements working at terahertz (THz) frequency. Both simulated and experimental results clearly show that there is a certain distance between the generated quasi-Bessel beam and this element. A physical analysis based on geometric optics theory is performed to explain the obtained results. Because it is a refractive transmitted optical element, we propose that it can be also realized at another frequency band if the relevant processing techniques are available.
Noncanonical projections to the hippocampal CA3 regulate spatial learning and memory by modulating the feedforward hippocampal trisynaptic pathway
Authors: Lin Xiaoxiao , Amalraj Michelle , Blanton Crisylle , Avila Brenda , Holmes Todd C. , Nitz Douglas A. , Xu Xiangmin
Published: December 2021

The hippocampal formation (HF) is well documented as having a feedforward, unidirectional circuit organization termed the trisynaptic pathway. This circuit organization exists along the septotemporal axis of the HF, but the circuit connectivity across septal to temporal regions is less well described. The emergence of viral genetic mapping techniques enhances our ability to determine the detailed complexity of HF circuitry. In earlier work, we mapped a subiculum (SUB) back projection to CA1 prompted by the discovery of theta wave back propagation from the SUB to CA1 and CA3. We reason that this circuitry may represent multiple extended noncanonical pathways involving the subicular complex and hippocampal subregions CA1 and CA3. In the present study, multiple retrograde viral tracing approaches produced robust mapping results, which supports this prediction. We find significant noncanonical synaptic inputs to dorsal hippocampal CA3 from ventral CA1 (vCA1), perirhinal cortex (Prh), and the subicular complex. Thus, CA1 inputs to CA3 run opposite the trisynaptic pathway and in a temporal to septal direction. Our retrograde viral tracing results are confirmed by anterograde-directed viral mapping of projections from input mapped regions to hippocampal dorsal CA3 (dCA3). We find that genetic inactivation of the projection of vCA1 to dCA3 impairs object-related spatial learning and memory but does not modulate anxiety-related behaviors. Our data provide a circuit foundation to explore novel functional roles contributed by these noncanonical hippocampal circuit connections to hippocampal circuit dynamics and learning and memory behaviors.
Revealing mechanisms of infectious disease spread through empirical contact networks
Authors: Sah Pratha , Otterstatter Michael , Leu Stephan T. , Leviyang Sivan , Bansal Shweta
Published: December 2021

The spread of pathogens fundamentally depends on the underlying contacts between individuals. Modeling the dynamics of infectious disease spread through contact networks, however, can be challenging due to limited knowledge of how an infectious disease spreads and its transmission rate. We developed a novel statistical tool, INoDS (Identifying contact Networks of infectious Disease Spread) that estimates the transmission rate of an infectious disease outbreak, establishes epidemiological relevance of a contact network in explaining the observed pattern of infectious disease spread and enables model comparison between different contact network hypotheses. We show that our tool is robust to incomplete data and can be easily applied to datasets where infection timings of individuals are unknown. We tested the reliability of INoDS using simulation experiments of disease spread on a synthetic contact network and find that it is robust to incomplete data and is reliable under different settings of network dynamics and disease contagiousness compared with previous approaches. We demonstrate the applicability of our method in two host-pathogen systems:Crithidia bombiin bumblebee colonies and Salmonella in wild Australian sleepy lizard populations. INoDS thus provides a novel and reliable statistical tool for identifying transmission pathways of infectious disease spread. In addition, application of INoDS extends to understanding the spread of novel or emerging infectious disease, an alternative approach to laboratory transmission experiments, and overcoming common data-collection constraints.
Internal state effects on behavioral shifts in freely behaving praying mantises (Tenodera sinensis)
Authors: Pickard Shanel C. , Bertsch David J. , Le Garrec Zoe , Ritzmann Roy E. , Quinn Roger D. , Szczecinski Nicholas S.
Published: December 2021

How we interact with our environment largely depends on both the external cues presented by our surroundings and the internal state from within. Internal states are the ever-changing physiological conditions that communicate the immediate survival needs and motivate the animal to behaviorally fulfill them. Satiety level constitutes such a state, and therefore has a dynamic influence on the output behaviors of an animal. In predatory insects like the praying mantis, hunting tactics, grooming, and mating have been shown to change hierarchical organization of behaviors depending on satiety. Here, we analyze behavior sequences of freely hunting praying mantises (Tenodera sinensis) to explore potential differences in sequential patterning of behavior as a correlate of satiety. First, our data supports previous work that showed starved praying mantises were not just more often attentive to prey, but also more often attentive to further prey. This was indicated by the increased time fraction spent in attentive bouts such as prey monitoring, head turns (to track prey), translations (closing the distance to the prey), and more strike attempts. With increasing satiety, praying mantises showed reduced time in these behaviors and exhibited them primarily towards close-proximity prey. Furthermore, our data demonstrates that during states of starvation, the praying mantis exhibits a stereotyped pattern of behavior that is highly motivated by prey capture. As satiety increased, the sequenced behaviors became more variable, indicating a shift away from the necessity of prey capture to more fluid presentations of behavior assembly.
Systematic evaluation of NIPT aneuploidy detection software tools with clinically validated NIPT samples
Authors: Paluoja Priit , Teder Hindrek , Ardeshirdavani Amin , Bayindir Baran , Vermeesch Joris , Salumets Andres , Krjutškov Kaarel , Palta Priit
Published: December 2021

Non-invasive prenatal testing (NIPT) is a powerful screening method for fetal aneuploidy detection, relying on laboratory and computational analysis of cell-free DNA. Although several published computational NIPT analysis tools are available, no prior comprehensive, head-to-head accuracy comparison of the various tools has been published. Here, we compared the outcome accuracies obtained for clinically validated samples with five commonly used computational NIPT aneuploidy analysis tools (WisecondorX, NIPTeR, NIPTmer, RAPIDR, and GIPseq) across various sequencing depths (coverage) and fetal DNA fractions. The sample set included cases of fetal trisomy 21 (Down syndrome), trisomy 18 (Edwards syndrome), and trisomy 13 (Patau syndrome). We determined that all of the compared tools were considerably affected by lower sequencing depths, such that increasing proportions of undetected trisomy cases (false negatives) were observed as the sequencing depth decreased. We summarised our benchmarking results and highlighted the advantages and disadvantages of each computational NIPT software. To conclude, trisomy detection for lower coverage NIPT samples (e.g. 2.5M reads per sample) is technically possible but can, with some NIPT tools, produce troubling rates of inaccurate trisomy detection, especially in low-FF samples.
Distinguishing gene flow between malaria parasite populations
Authors: Brown Tyler S. , Arogbokun Olufunmilayo , Buckee Caroline O. , Chang Hsiao-Han
Published: December 2021

Measuring gene flow between malaria parasite populations in different geographic locations can provide strategic information for malaria control interventions. Multiple important questions pertaining to the design of such studies remain unanswered, limiting efforts to operationalize genomic surveillance tools for routine public health use. This report examines the use of population-level summaries of genetic divergence (FST) and relatedness (identity-by-descent) to distinguish levels of gene flow between malaria populations, focused on field-relevant questions about data size, sampling, and interpretability of observations from genomic surveillance studies. To do this, we use P. falciparum whole genome sequence data and simulated sequence data approximating malaria populations evolving under different current and historical epidemiological conditions. We employ mobile-phone associated mobility data to estimate parasite migration rates over different spatial scales and use this to inform our analysis. This analysis underscores the complementary nature of divergence- and relatedness-based metrics for distinguishing gene flow over different temporal and spatial scales and characterizes the data requirements for using these metrics in different contexts. Our results have implications for the design and implementation of malaria genomic surveillance studies.
Domestication reshaped the genetic basis of inbreeding depression in a maize landrace compared to its wild relative, teosinte
Authors: Samayoa Luis Fernando , Olukolu Bode A. , Yang Chin Jian , Chen Qiuyue , Stetter Markus G. , York Alessandra M. , Sanchez-Gonzalez Jose de Jesus , Glaubitz Jeffrey C. , Bradbury Peter J. , Romay Maria Cinta , Sun Qi , Yang Jinliang , Ross-Ibarra Jeffrey , Buckler Edward S. , Doebley John F. , Holland James B.
Published: December 2021

Inbreeding depression is the reduction in fitness and vigor resulting from mating of close relatives observed in many plant and animal species. The extent to which the genetic load of mutations contributing to inbreeding depression is due to large-effect mutations versus variants with very small individual effects is unknown and may be affected by population history. We compared the effects of outcrossing and self-fertilization on 18 traits in a landrace population of maize, which underwent a population bottleneck during domestication, and a neighboring population of its wild relative teosinte. Inbreeding depression was greater in maize than teosinte for 15 of 18 traits, congruent with the greater segregating genetic load in the maize population that we predicted from sequence data. Parental breeding values were highly consistent between outcross and selfed offspring, indicating that additive effects determine most of the genetic value even in the presence of strong inbreeding depression. We developed a novel linkage scan to identify quantitative trait loci (QTL) representing large-effect rare variants carried by only a single parent, which were more important in teosinte than maize. Teosinte also carried more putative juvenile-acting lethal variants identified by segregation distortion. These results suggest a mixture of mostly polygenic, small-effect partially recessive effects in linkage disequilibrium underlying inbreeding depression, with an additional contribution from rare larger-effect variants that was more important in teosinte but depleted in maize following the domestication bottleneck. Purging associated with the maize domestication bottleneck may have selected against some large effect variants, but polygenic load is harder to purge and overall segregating mutational burden increased in maize compared to teosinte.
The epidemiological characteristics of dengue in high-risk areas of China, 2013–2016
Authors: Sang Shaowei , Liu Qiyong , Guo Xiaofang , Wu De , Ke Changwen , Liu-Helmersson Jing , Jiang Jinyong , Weng Yuwei , Wang Yiguan
Published: December 2021

Introduction

Dengue has become a more serious human health concern in China, with increased incidence and expanded outbreak regions. The knowledge of the cross-sectional and longitudinal epidemiological characteristics and the evolutionary dynamics of dengue in high-risk areas of China is limited.

Methods

Records of dengue cases from 2013 to 2016 were obtained from the China Notifiable Disease Surveillance System. Full envelope gene sequences of dengue viruses detected from the high-risk areas of China were collected. Maximum Likelihood tree and haplotype network analyses were conducted to explore the phylogenetic relationship of viruses from high-risk areas of China.

Results

A total of 56,520 cases was reported in China from 2013 to 2016. During this time, Yunnan, Guangdong and Fujian provinces were the high-risk areas. Imported cases occurred almost year-round, and were mainly introduced from Southeast Asia. The first indigenous case usually occurred in June to August, and the last one occurred before December in Yunnan and Fujian provinces but in December in Guangdong Province. Seven genotypes of DENV 1–3 were detected in the high-risk areas, with DENV 1-I the main genotype and DENV 2-Cosmopolitan the secondary one. The Maximum Likelihood trees show that almost all the indigenous viruses separated into different clusters. DENV 1-I viruses were found to be clustered in Guangdong Province, but not in Fujian and Yunnan, from 2013 to 2015. The ancestors of the Guangdong viruses in the cluster in 2013 and 2014 were most closely related to strains from Thailand or Singapore, and the Guangdong virus in 2015 was most closely related to the Guangdong virus of 2014. Based on closest phylogenetic relationships, viruses from Myanmar possibly initiated further indigenous cases in Yunnan, those from Indonesia in Fujian, while viruses from Thailand, Malaysia, Singapore and Indonesia were predominant in Guangdong Province.

Conclusions

Dengue is still an imported disease in China, although some genotypes continued to circulate in successive years. Viral phylogenies based on the envelope gene suggested periodic introductions of dengue strains into China, primarily from Southeast Asia, with occasional sustained, multi-year transmission in some regions of China.
Structural and functional insights into the first Bacillus thuringiensis vegetative insecticidal protein of the Vpb4 fold, active against western corn rootworm
Authors: Kouadio Jean-Louis , Zheng Meiying , Aikins Michael , Duda David , Duff Stephen , Chen Danqi , Zhang Jun , Milligan Jason , Taylor Christina , Mamanella Patricia , Rydel Timothy , Kessenich Colton , Panosian Timothy , Yin Yong , Moar William , Giddings Kara , Park Yoonseong , Jerga Agoston , Haas Jeffrey
Published: December 2021

The western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, is a major maize pest in the United States causing significant economic loss. The emergence of field-evolved resistant WCR to Bacillus thuringiensis (Bt) traits has prompted the need to discover and deploy new insecticidal proteins in transgenic maize. In the current study we determined the crystal structure and mode of action (MOA) of the Vpb4Da2 protein (formerly known as Vip4Da2) from Bt, the first identified insecticidal Vpb4 protein with commercial level control against WCR. The Vpb4Da2 structure exhibits a six-domain architecture mainly comprised of antiparallel β-sheets organized into β-sandwich layers. The amino-terminal domains 1–3 of the protein share structural homology with the protective antigen (PA) PA14 domain and encompass a long β-pore forming loop as in the clostridial binary-toxB module. Domains 5 and 6 at the carboxyl-terminal half of Vpb4Da2 are unique as this extension is not observed in PA or any other structurally-related protein other than Vpb4 homologs. These unique Vpb4 domains adopt the topologies of carbohydrate-binding modules known to participate in receptor-recognition. Functional assessment of Vpb4Da2 suggests that domains 4–6 comprise the WCR receptor binding region and are key in conferring the observed insecticidal activity against WCR. The current structural analysis was complemented by in vitro and in vivo characterizations, including immuno-histochemistry, demonstrating that Vpb4Da2 follows a MOA that is consistent with well-characterized 3-domain Bt insecticidal proteins despite significant structural differences.
Cost-effectiveness of HPV vaccination in 195 countries: A meta-regression analysis
Authors: Rosettie Katherine L. , Joffe Jonah N. , Sparks Gianna W. , Aravkin Aleksandr , Chen Shirley , Compton Kelly , Ewald Samuel B. , Mathew Edwin B. , Michael Danielle , Pedroza Velandia Paola , Miller-Petrie Molly B. , Stafford Lauryn , Zheng Peng , Weaver Marcia R. , Murray Christopher J. L.
Published: December 2021

Cost-effectiveness analysis (CEA) is a well-known, but resource intensive, method for comparing the costs and health outcomes of health interventions. To build on available evidence, researchers are developing methods to transfer CEA across settings; previous methods do not use all available results nor quantify differences across settings. We conducted a meta-regression analysis of published CEAs of human papillomavirus (HPV) vaccination to quantify the effects of factors at the country, intervention, and method-level, and predict incremental cost-effectiveness ratios (ICERs) for HPV vaccination in 195 countries. We used 613 ICERs reported in 75 studies from the Tufts University’s Cost-Effectiveness Analysis (CEA) Registry and the Global Health CEA Registry, and extracted an additional 1,215 one-way sensitivity analyses. A five-stage, mixed-effects meta-regression framework was used to predict country-specific ICERs. The probability that HPV vaccination is cost-saving in each country was predicted using a logistic regression model. Covariates for both models included methods and intervention characteristics, and each country’s cervical cancer burden and gross domestic product per capita. ICERs are positively related to vaccine cost, and negatively related to cervical cancer burden. The mean predicted ICER for HPV vaccination is 2017 US$4,217 per DALY averted (95% uncertainty interval (UI): US$773–13,448) globally, and below US$800 per DALY averted in 64 countries. Predicted ICERs are lowest in Sub-Saharan Africa and South Asia, with a population-weighted mean ICER across 46 countries of US$706 per DALY averted (95% UI: $130–2,245), and across five countries of US$489 per DALY averted (95% UI: $90–1,557), respectively. Meta-regression analyses can be conducted on CEA, where one-way sensitivity analyses are used to quantify the effects of factors at the intervention and method-level. Building on all published results, our predictions support introducing and expanding HPV vaccination, especially in countries that are eligible for subsidized vaccines from GAVI, the Vaccine Alliance, and Pan American Health Organization.
Genetic risk factors associated with gestational diabetes in a multi-ethnic population
Authors: Benny Paula , Ahn Hyeong Jun , Burlingame Janet , Lee Men-Jean , Miller Corrie , Chen John , Urschitz Johann
Published: December 2021

Aims

Genome-wide association studies have shown an increased risk of type-2-diabetes (T2DM) in patients who carry single nucleotide polymorphisms in several genes. We investigated whether the same gene loci confer a risk for gestational diabetes mellitus (GDM) in women from Hawaii, and in particular, Pacific Islander and Filipino populations.

Methods

Blood was collected from 291 women with GDM and 734 matched non-diabetic controls (Pacific Islanders: 71 GDM, 197 non-diabetic controls; Filipinos: 162 GDM, 395 controls; Japanese: 58 GDM, 142 controls). Maternal DNA was used to genotype and show allele frequencies of 25 different SNPs mapped to 18 different loci.

Results

After adjusting for age, BMI, parity and gravidity by multivariable logistic regression, several SNPs showed significant associations with GDM and were ethnicity specific. In particular, SNPs rs1113132 (EXT2), rs1111875 (HHEX), rs2237892 (KCNQ1), rs2237895 (KCNQ1), rs10830963 (MTNR1B) and rs13266634 (SLC30A8) showed significant associations with GDM in Filipinos. For Japanese, SNPs rs4402960 (IGFBP2) and rs2237892 (KCNQ1) were significantly associated with GDM. For Pacific Islanders, SNPs rs10830963 (MTNR1B) and rs13266634 (SLC30A8) showed significant associations with GDM. Individually, none of the SNPs showed a consistent association with GDM across all three investigated ethnicities.

Conclusion

Several SNPs associated with T2DM are found to confer increased risk for GDM in a multiethnic cohort in Hawaii.
Characterization of increased mucus production of HT29-MTX-E12 cells grown under Semi-Wet interface with Mechanical Stimulation
Authors: Elzinga Janneke , van der Lugt Benthe , Belzer Clara , Steegenga Wilma T.
Published: December 2021

The intestinal mucus layer plays a crucial role in human health. To study intestinal mucus function and structure in vitro, the mucus-producing intestinal cell line HT29-MTX-E12 has been commonly used. However, this cell line produces only low amounts of the intestine-specific MUC2. It has been shown previously that HT29-MTX-E12 cells cultured under Semi-Wet interface with Mechanical Stimulation (SWMS) produced higher amounts of MUC2, concomitant with a thicker mucus layer, compared to cells cultured conventionally. However, it remains unknown which underlying pathways are involved. Therefore, we aimed to further explore the cellular processes underlying the increased MUC2 production by HT29-MTX-E12 cells grown under SWMS conditions. Cells grown on Transwell membranes for 14 days under static and SWMS conditions (after cell seeding and attachment) were subjected to transcriptome analysis to investigate underlying molecular pathways at gene expression level. Caco-2 and LS174T cell lines were included as references. We characterized how SWMS conditions affected HT29-MTX-E12 cells in terms of epithelial barrier integrity, by measuring transepithelial electrical resistance, and cell metabolism, by monitoring pH and lactate production per molecule glucose of the conditioned medium. We confirmed higher MUC2 production under SWMS conditions at gene and protein level and demonstrated that this culturing method primarily stimulated cell growth. In addition, we also found evidence for a more aerobic cell metabolism under SWMS, as shown previously for similar models. In summary, we suggest different mechanisms by which MUC2 production is enhanced under SWMS and propose potential applications of this model in future studies.
Prevalence of perceived stigma and associated factors among primary caregivers of children and adolescents with mental illness, Addis Ababa, Ethiopia: Cross-sectional study
Authors: Minichil Woredaw , Getinet Wondale , Kassew Tilahun
Published: December 2021

Background

Mental illness exposes persons to stigma and this stigma also affects family caregivers of persons with mental illness. The objective of the study was to assess the prevalence of perceived stigma and associated factors among primary caregivers of children and adolescents with mental illness, Addis Ababa, Ethiopia.

Methods

A cross-sectional study design and systematic random sampling technique were used to recruit 408 participants at St. Paul’s Hospital Millennium Medical College and Yekatit-12 Hospital Medical College, Addis Ababa, Ethiopia. We collected the data by face-to-face interview. Devaluation of Consumer Families Scale was used to measure perceived stigma. Patient Health Questionnaire-9 and Oslo-3 social support scale were the instruments used to assess the factors. Coded variables were entered into Epidata V.3.1 and exported to SPSS V.21 for analysis. Binary logistic regression was used for analysis.

Result

A total of 408 participants were interviewed, with a response rate of 96.5%. The magnitude of perceived stigma was 38.5% with 95% CI (33.6-43.1). Majority (68.6%) of the respondents were female. In the multivariate logistic regression, being mother (AOR = 2.8, 95% CI: 1.59, 4.91), absence of other caregiver (AOR = 2.0, 95% CI: 1.15, 3.49), poor social support (AOR = 3.9, 95% CI: 1.59, 6.13), and symptoms of depression (AOR = 2.9, 95% CI: 1.88, 3.65) were factors significantly associated with perceived stigma.

Conclusion

The prevalence of perceived stigma among primary caregivers of children and adolescents with mental illness was high. Being mother, absence of other caregiver, poor social support, and symptoms of depression were factors significantly associated with perceived stigma.
Alcohol withdrawal syndrome in ICU patients: Clinical features, management, and outcome predictors
Authors: Vigouroux Aliénor , Garret Charlotte , Lascarrou Jean-Baptiste , Martin Maëlle , Miailhe Arnaud-Félix , Lemarié Jérémie , Dupeyrat Julien , Zambon Olivier , Seguin Amélie , Reignier Jean , Canet Emmanuel
Published: December 2021

Background

Alcohol withdrawal syndrome (AWS) is a common condition in hospitalized patients, yet its epidemiology in the ICU remains poorly characterized.

Methods

Retrospective cohort of patients admitted to the Nantes University Hospital ICU between January 1, 2017, and December 31, 2019, and coded for AWS using ICD-10 criteria. The objective of the study was to identify factors associated with complicated hospital stay defined as ICU length of stay ≥7 days or hospital mortality.

Results

Among 5,641 patients admitted to the ICU during the study period, 246 (4.4%) were coded as having AWS. Among them, 42 had exclusion criteria and 204 were included in the study. The three main reasons for ICU admission were sepsis (29.9%), altered consciousness (29.4%), and seizures (24%). At ICU admission, median Cushman’s score was 6 [4–9] and median SOFA score was 3 [2–6]. Delirium tremens occurred in half the patients, seizures in one fifth and pneumonia in one third. Overall, 48% of patients developed complicated hospital stay, of whom 92.8% stayed in the ICU for ≥7 days, 36.7% received MV for ≥7 days, and 16.3% died during hospital stay. By multivariable analysis, two factors were associated with complicated hospital stay: a higher number of organ dysfunctions at ICU admission was associated with a higher risk of complicated hospital stay (OR, 1.18; 95CI, 1.05–1.32, P = 0.005), whereas ICU admission for seizures was associated with a lower risk of complicated hospital stay (OR, 0.14; 95%CI, 0.026–0.80; P = 0.026).

Conclusions

AWS in ICU patients chiefly affects young adults and is often associated with additional factors such as sepsis, trauma, or surgery. Half the patients experienced an extended ICU stay or death during the hospital stay. The likelihood of developing complicated hospital stay relied on the reason for ICU admission and the number of organ dysfunctions at ICU admission.
Difference in predictors and barriers to arts and cultural engagement with age in the United States: A cross-sectional analysis using the Health and Retirement Study
Authors: Fluharty Meg , Paul Elise , Bone Jessica , Bu Feifei , Sonke Jill , Fancourt Daisy
Published: December 2021

Introduction

Arts and cultural engagement are associated with a range of mental and physical health benefits, including promoting heathy aging and lower incidence of age-related disabilities such as slower cognitive decline and slower progression of frailty. This suggests arts engagement constitutes health-promoting behaviour in older age. However, there are no large-scale studies examining how the predictors of arts engagement vary with age.

Methods

Data from the Health and Retirement Study (2014) were used to identify sociodemographic, life satisfaction, social, and arts appreciation predictors of (1) frequency of arts engagement, (2) cultural attendance, (3) difficulty participating in the arts, and (4) being an interested non-attendee of cultural events. Logistic regression models were stratified by age groups [50–59, 60–69, ≥70] for the frequency of arts participation outcome and [50–69 vs ≥70] all other outcomes.

Results

Findings indicated a number of age-related predictors of frequent arts engagement, including gender, educational attainment, wealth, dissatisfaction with aging, and instrumental activities of daily living (iADL). For cultural event attendance, lower interest in the arts predicted lack of engagement across age groups, whereas higher educational attainment and more frequent religious service attendance became predictors in older age groups (≥ 70). Adults in both age groups were less likely to report difficulties engaging in the arts if they had lower neighbourhood safety, whilst poor self-rated health and low arts appreciation also predicted reduced likelihood of this outcome, but only in the younger (50–69) age group. Adults in the older (≥ 70) age group were more likely to be interested non-attendees of cultural events if they had higher educational attainment and less likely if they lived in neighbourhoods with low levels of safety.

Conclusions

Our results suggest that certain factors become stronger predictors of arts and cultural engagement and barriers to engagement as people age. Further, there appear to be socioeconomic inequalities in engagement that may increase in older ages, with arts activities overall more accessible as individuals age compared to cultural engagement due to additional financial barriers and transportation barriers. Ensuring that these activities are accessible to people of all ages will allow older adults to benefit from the range of health outcomes gained from arts and cultural engagement.
The pigtail macaque (Macaca nemestrina) model of COVID-19 reproduces diverse clinical outcomes and reveals new and complex signatures of disease
Authors: Melton Alexandra , Doyle-Meyers Lara A. , Blair Robert V. , Midkiff Cecily , Melton Hunter J. , Russell-Lodrigue Kasi , Aye Pyone P. , Schiro Faith , Fahlberg Marissa , Szeltner Dawn , Spencer Skye , Beddingfield Brandon J. , Goff Kelly , Golden Nadia , Penney Toni , Picou Breanna , Hensley Krystle , Chandler Kristin E. , Plante Jessica A. , Plante Kenneth S. , Weaver Scott C. , Roy Chad J. , Hoxie James A. , Gao Hongmei , Montefiori David C. , Mankowski Joseph L. , Bohm Rudolf P. , Rappaport Jay , Maness Nicholas J.
Published: December 2021

The novel coronavirus SARS-CoV-2, the causative agent of COVID-19 disease, has killed over five million people worldwide as of December 2021 with infections rising again due to the emergence of highly transmissible variants. Animal models that faithfully recapitulate human disease are critical for assessing SARS-CoV-2 viral and immune dynamics, for understanding mechanisms of disease, and for testing vaccines and therapeutics. Pigtail macaques (PTM,Macaca nemestrina) demonstrate a rapid and severe disease course when infected with simian immunodeficiency virus (SIV), including the development of severe cardiovascular symptoms that are pertinent to COVID-19 manifestations in humans. We thus proposed this species may likewise exhibit severe COVID-19 disease upon infection with SARS-CoV-2. Here, we extensively studied a cohort of SARS-CoV-2-infected PTM euthanized either 6- or 21-days after respiratory viral challenge. We show that PTM demonstrate largely mild-to-moderate COVID-19 disease. Pulmonary infiltrates were dominated by T cells, including CD4+ T cells that upregulate CD8 and express cytotoxic molecules, as well as virus-targeting T cells that were predominantly CD4+. We also noted increases in inflammatory and coagulation markers in blood, pulmonary pathologic lesions, and the development of neutralizing antibodies. Together, our data demonstrate that SARS-CoV-2 infection of PTM recapitulates important features of COVID-19 and reveals new immune and viral dynamics and thus may serve as a useful animal model for studying pathogenesis and testing vaccines and therapeutics.